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SOUTH WESTERN RIVER BASIN DISTRICT

RECOMMENDATIONS FOR PROGRAMMES OF MEASURES

FOR

POINT SOURCE DISCHARGES

TO

SURFACE WATERS RESULTING FROM

MUNICIPAL AND INDUSTRIAL REGULATED ACTIVITIES

(MIR POMS Study)

VOLUME 1

South Western River Basin District Project Office

5 Eastgate Avenue Eastgate

Little Island

Co. Cork

Job Nr. : PA8906 July 2008

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Revision Control Table

User Is Responsible for Checking the Revision Status of this Document

For & On Behalf of SWRBD Project Office Rev

Nr.

Description of Changes Prepared

by

Checked

by

Approved

by

Date

A Draft for Review F. McGivern June 2008

B Approved by MIR Steering Group F. McGivern R. McEvoy July 2008

No part of this document may be re-produced or transmitted in any form or stored in any retrieval system of any nature, without the written permission of the SWRBD Project Office, as Copyright Holder, except as agreed for

use on this specific project.

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ACKNOWLEDGEMENTS

The South Western River Basin District Programmes of Measures and Standards Project Consultants would like to thank all those who have provided data, information and advice for this study. Particular thanks must go to the Municipal and Industrial Regulations (MIR) Steering Group and Advisors from the Department of Environment, Heritage and Local Government (DEHLG), particularly the Water Services Inspectorate and the National Parks & Wildlife (NPWS) Division, The Environmental Protection Agency (EPA) and Water Services Authority personnel. The MIR steering group consisted of Tadhg O Connor DEHLG, Peter Webster EPA, David Smith EPA, Edmond Flynn Cork County Council, Oliver Ring Kerry County Council, Matt Short North Tipperary County Council, Paul Crowe Limerick County Council, Tom Hernon Galway City Council, Ray Earle Project Co-ordinator ERBD, Seán Ó Breasail Project Co-ordinator SWRBD. The following organisations have provided their data for use in this project: Department of Environment, Heritage and Local Government Environmental Protection Agency National Parks and Wildlife Service SERBD: Project Co-ordinators Lisa Sheils and Ray Spain SHIRBD: Project Co-ordinator Enda Thompson WRBD: Project Co-ordinator Pat Canney ERBD: Project Co-ordinator Ray Earle N-S Share Project: Project Co-ordinator Tony McNally Water Services Authorities: Carlow County Council, Cavan County Council, Clare County Council, Cork City Council, Cork County Council North, Cork County Council South, Cork County Council West, Donegal County Council, Dublin City Council, Dun Laoghaire-Rathdown County Council, Fingal County Council, Galway City Council, Galway County Council, Kerry County Council, Kildare County Council, Kilkenny County Council, Laois County Council, Leitrim County Council, Limerick City Council, Limerick County Council, Longford County Council, Louth County Council, Mayo County Council, Meath County Council, Monaghan County Council, North Tipperary County Council, Offaly County Council, Roscommon County Council, Sligo County Council, South Tipperary County Council, Waterford City Council, Waterford County Council, Westmeath County Council, Wexford County Council, Wicklow County Council. The following sub-consultants also participated in the study. WRc Plc. - Development of SIMCAT model for SWRBD RPS Consulting Engineers - Development of a population projection methodology.

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Volume 1

Recommendations for Programmes of Measures for Point Source Discharges to Surface

Waters Resulting From Municipal and Industrial Regulated Activities

(MIR POMS Study)

TABLE OF CONTENTS

Page

1.0 INTRODUCTION..................................................................................................1

2.0 OBJECTIVES.........................................................................................................2

3.0 SCOPE OF WORKS AND OUTLINE METHODOLOGY...............................3

3.1 General...........................................................................................................3 3.2 Task 1 Data Review, Data Gaps and Additional Data..............................3 3.3 Task 2 Report on Measurement Equipment at WWTPs .........................4 3.4 Task 3 Characterisation of Urban Wastewater ........................................4 3.5 Task 4 Population Growth Projections......................................................4 3.6 Task 5 Revised Risk Assessment.................................................................4 3.7 Task 6 Prioritisation of Measures...............................................................4 3.8 Task 7 Development of SIMCAT Model for SWRBD..............................5

4.0 MEASUREMENT AT WASTE WATER TREATMENT PLANTS ................6 4.1 Introduction...................................................................................................6 4.2 Background....................................................................................................6 4.3 Review of the 2003 Waste Water Returns ..................................................7 4.4 Scope & Methodology...................................................................................8 4.5 Analysis of the Information Received.........................................................8 4.6 Conclusions..................................................................................................10 4.7 Recommendations.......................................................................................12

5.0 CHARACTERISTICS OF URBAN WASTE WATER....................................14

5.1 Introduction.................................................................................................14 5.2 Background..................................................................................................14 5.3 Part 1 - Desktop Study................................................................................15 5.4 Part 2 - Field Sampling and Analyses .......................................................19

6.0 POPULATION GROWTH PROJECTIONS....................................................27

6.1 Introduction.................................................................................................27 6.2 Scope.............................................................................................................27 6.3 Development of Methodology....................................................................27 6.3 Updated Methodology.................................................................................30 6.4 Conclusion....................................................................................................33

7.0 WATER BODIES AT RISK FROM POINT SOURCE DISCHARGES .......34 7.1 Introduction.................................................................................................34 7.2 Background..................................................................................................34 7.3 Sensitivity of the Receiving Waters ...........................................................35 7.4 Further Characterisation – Updated Risk Assessment...........................38

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8.0 PRIORITISATION OF WATER BODIES AT RISK......................................38

8.1 Introduction.................................................................................................38 8.2 Background..................................................................................................38 8.3 Prioritising the Implementation of the Programme of Measures...........38 8.4 Criteria for prioritisation...........................................................................38

9.0 DEVELOPMENT OF SIMCAT MODEL FOR SWRBD................................38

9.1 Introduction.................................................................................................38 9.2 Objectives.....................................................................................................38 9.3 Establishment of the Model – Stages of Development.............................38 9.4 Development of Model Applications .........................................................38 9.5 Conclusions..................................................................................................38

10.0 PROPOSED PROGRAMME OF MEASURES................................................38 10.1 Background..................................................................................................38 10.2 Definition of Measures................................................................................38 10.3 Proposed Measures for Water Bodies at Risk from Point Source

Discharges....................................................................................................38 10.4 Summary of Measures................................................................................38

Volume 2 Appendices

Appendix A Position Paper on Flow Monitoring and Sampling Facilities at

Municipal Waste Water Treatment Plants (Volumes 1 & 2)

Appendix B Reports on Characteristics of Urban Waste Water

Appendix C1 Pilot Project for Cork City and County Area - Population Forecasting

Methodology

Appendix C2 National Population Projections and Regional Population Targets 2006 – 2020

Appendix C3 Population Projection Results for 2015

Appendix D SIMCAT Model for SWRBD – Final Report

Appendix E Water Bodies Risk Register

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GLOSSARY OF TERMS AND ABBREVIATIONS

AA Annual allowable concentration BOD Biochemical oxygen demand CASP The Cork Area Strategic Plan CIS Common Implementation Strategy COD Chemical oxygen demand DEHP Di(2-ethylhexyl)-pthalate d/s Downstream E.C. European Community E. coli Escherichia coli

EA Environment Agency EPA Environmental Protection Agency EQS Environmental Quality Standards FWD Food waste disintegrators GIS Geographic information system IP(P)C Integrated Pollution (Prevention) Control LAP Local Area Plan LOD Limit of detection Daily mean flow

Daily mean values of flow in the water body over the past year. Flow values are calculated using the appropriate rating curve.

mg/l Concentration, milligrams per litre MIR Municipal and Industrial Regulation NTCG National Technical Co-ordination Group (for implementation of the

WFD) OPW Office of Public Works OSI Ordinance Survey Ireland PAH Polycyclic aromatic hydrocarbons PCA Polychloroalkanes PCB Polychlorinated biphenyls PCG Programmes of Measures and Standards Co-Ordination Group PCDD/F Polychlorinated dibenzodioxins/dibenzofurans POM Programme of Measures Population

equivalent

Measurement of organic biodegradable load and a population equivalent of 1 (1p.e.) means the organic biodegradable load having a five-day biochemical oxygen demand (BOD5) of 60g of oxygen per day

Pressure The direct effect of the driver (for example, an effect that causes a change in flow or a change in the water chemistry of surface and groundwater bodies.

Q value Biological Quality Ratings used by EPA RPG Regional Planning Guidelines River River means a body of inland water flowing for the most part on the

surface of the land but which may flow underground for part of its course.

River Basin District (RBD)

A River Basin District includes coastal/marine waters up to one nautical mile beyond the baseline from which territorial waters are measured. It is an area of land and sea made up of one or more neighbouring river basins together with their associated groundwater, and coastal water.

Section 4 Licensed discharges to water courses (Local Government Water Pollution Act).

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SIMCAT Simulated catchment model used to predict water quality in river systems.

SLAP Special Local Area Plan SS Suspended Solids SWRBD South Western River Basin District SWRPG South West Regional Planning Guidelines Transitional Transitional waters are bodies of surface water in the vicinity of river

mouths which are partly saline in character as a result of their proximity to coastal waters but which are substantially influenced by freshwater flows.

u/s Upstream Waterbody The basic compliance reporting and management unit for the Water

Framework Directive into which all rivers, lakes, ground, transitional and coastal water are divided.

WFD Water Framework Directive – Directive 2000/60/EC establishing a framework for Community action in the field of water.

Water Services

Authority

County Council or a City Council and any references to a Sanitary Authority or Local Authority in so far as it relates to functions of that authority in relation to water services, shall be regarded as a reference to a Water Services Authority

WWTP Waste Water Treatment Plant µg/l Concentration, micrograms per litre 95%ile flow A statistical measure of flow-rate in the waterbody.

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1.0 INTRODUCTION

1.1 The Water Framework Directive (WFD), Directive 2000/60/EC, came into

force on 23rd October 2000, and the Irish Regulations implementing the Directive (S.I. No. 722 of 2003) were signed by the Minister for the Environment, Heritage and Local Government on 22nd December 2003.

The implementation of the Directive requires the production of various reports,

programmes, registers, plans, etc., some of which include the following:- • Characterisation Report (Article 5). • Programmes for Monitoring Water Status (Article 8). • Significant Water Management Issues Report (Article 14). • Programme of Measures (Article 11). • River Basin Management Plans (Article 13). The first three of the above list have been completed and work is progressing

on the Programmes of Measures and the production of the River Basin Management Plans.

A National Technical Co-ordination Group (NTCG) has been established

under the auspices of the Environmental Protection Agency. The remit of this group is to provide guidance and co-ordination of the activities of the River Basin District project teams contracted to implement the requirements of the Framework Directive. The NTCG set up a sub-group to oversee studies to underpin the measures that would be required to meet WFD objectives and to support the development of environmental quality standards (EQSs). This sub-group is called the Programme of Measures and Standards Co-ordination Group (PCG).

The PCG assigned specific tasks to each RBD project to be carried out

nationally on behalf of all river basin districts (RBDs). One of the tasks assigned to the South Western River Basin District (SWRBD) concerns the identification of measures to be applied to point source discharges to surface waters. Point source discharges refer to municipal waste water discharges and licensed industrial discharges which are regulated by Water Services Authorities or the EPA. For this reason, this study is known as the Municipal and Industrial Regulation Study (MIR). This report describes the tasks undertaken by the SWRBD to identify the water quality management issues associated with point source discharges and recommendations are provided concerning appropriate measures to be implemented in respect of point source discharges to meet the objectives of the Water Framework Directive.

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2.0 OBJECTIVES

The WFD Article 5 Characterisation Report was submitted to the European

Commission on 22nd March 2005. The Report presents the results of a comprehensive risk assessment which was undertaken to categorise water bodies according to their risk of achieving or not achieving good quality status by 2015. The risk assessments took into consideration the significant pressures on water bodies resulting from human activities and also impact data available on water quality.

The risk assessment identified water bodies which were considered to be “at

risk” of failing the environmental quality objectives of the Directive. Section 1.5 of Annex 2 of the WFD requires that for water bodies identified as being at risk, further characterisation shall be carried out to optimise the design of both the monitoring programmes and the programmes of measures.

The risk assessment which was carried out as part of the Article 5

Characterisation Report in respect of point source discharges was limited by the information available within the timeframe for the production of that report. The risk assessment considered the degree of compliance of each point source discharge with the requirements for treated effluent quality and the frequency of sampling. No account was taken of the assimilative capacity of the receiving waters or of the added risk to water quality from increasing pollution loading resulting from population growth.

The objective of the MIR Project was to source additional data on the

magnitude of the point source discharges and on the impacts on the receiving water, and to use this information to further characterise water bodies according to their risk status and to identify appropriate programmes of measures for those water bodies considered to be “at risk” of failing to meet water quality objectives.

There were a number of issues related to municipal wastewater treatment

which were not part of the study including the disposal of sewage sludge and changes in the characteristics of wastewater arising from food waste disintegrators (FWDs) and the disposal of fats, oils and greases to sewers. There is an absence of regulatory control regarding the disposal of such wastes to municipal treatment plants.

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3.0 SCOPE OF WORKS AND OUTLINE METHODOLOGY

3.1 General

Point source discharges refer to discharges from urban waste water treatment

plants, licensed discharges to surface waters regulated by the EPA, and licensed discharges regulated by Water Services Authorities. Combined storm overflows (CSOs) are not included in the scope of the study. CSOs in urban areas are being further assessed in a study of Urban Pressures being undertaken by the Eastern River Basin District (ERBD).

The SWRBD was requested to consider the objectives of the MIR study and to

identify tasks to be undertaken to meet these objectives. These tasks were set out in a Terms of Reference (TOR) which were reviewed and approved by the PCG.

The Terms of Reference identified the following tasks. Task 1 Data review, data gaps and additional data Task 2 Report on measurement equipment at urban waste water

treatment plants Task 3 Characteristics of urban waste water Task 4 Population growth projections Task 5 Revised point source discharges risk assessment Task 6 Prioritisation of measures Task 7 Development of SIMCAT model for SWRBD 3.2 Task 1 Data Review, Data Gaps and Additional Data

This task involved reviewing the datasets that were used in the Initial Characterisation Report, identifying the data gaps and obtaining additional data required for the study. The datasets could broadly be categorised into pressure datasets and impact datasets and included the following:-

- Local Authority returns to the EPA on urban waste water treatment

plants - Local Authority records of Section 4 licences - Copies of IPC/IPPC licenses issued by the EPA - Census data on populations within catchments of WWTPs - EPA records from hydrometric stations - Published river water quality reports

Data gaps were identified in the available information and the SWRBD was

tasked with using best estimates in order to fill in these data gaps, based on expert judgement, applying industry norms, using GIS techniques and using estimating tools (such as in flow estimation). The task also included: • Addressing data gaps in locations and national grid references of point

source discharges. • Collation of monitoring data nationally for each type of discharge • Collation of discharge flow volumes nationally

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3.3 Task 2 Report on Measurement Equipment at WWTPs

The SWRBD identified in the TOR that there was a gap in the information

provided by Local Authorities concerning flow and monitoring data at urban waste water treatment plants. Only 33% of the plants in the 2003 Local Authority Urban Wastewater returns to the EPA provided average daily flow records. The SWRBD set itself the task of investigating the reasons for the deficit in this type of information.

3.4 Task 3 Characterisation of Urban Wastewater

Urban waste water is generally characterised and reported with reference to a narrow band of general chemicals. However, urban waste water is more complex and contains a wide range of substances which have the potential to impact on the quality status of the receiving waters.

The SWRBD sought to investigate the characteristics of urban waste water to

determine the impact on the receiving water with reference to the proposed Environmental Quality Standards. This task included an element of field work including analyses of samples of effluent and sludge from waste water treatment plants and analyses of samples of receiving waters.

The objective of the field work was to determine the concentration of certain

ubiquitous substances in treated effluent and sludge and assess their impact on the chemical and ecological status of the receiving water bodies. The study also included the sampling and testing at a number of waste water treatment plants that accept leachate from landfills.

3.5 Task 4 Population Growth Projections

Increasing population results in increasing pollution loading to WWTPs

thereby increasing the risk that ‘Good Status’ in the receiving waters may not be achieved. In order to achieve the objectives of the WFD, it was necessary to predict increasing pressures resulting from population growth in urban areas, thereby estimating likely future pollution loads and their consequent impact on receiving waters.

3.6 Task 5 Revised Risk Assessment

The risk assessment for point source discharges which was carried out for the Article 5 report considered compliance with discharge standards and frequency of sampling as the basis of the risk assessment. The information gathered under Tasks 1, 3 and 4 was to be used to define more accurately the risk posed to waterbodies by point source discharges. The output of this task would provide a designation of water bodies ‘at risk’ for which programmes of measures would be implemented.

3.7 Task 6 Prioritisation of Measures

The WFD specifies time constraints by which certain objectives have to be met or measures put in place. Measures required to achieve the objectives in respect of Protected Areas and measures intended to arrest the deterioration in existing water quality and to maintain existing Good Status are of greatest urgency. It

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is also recognised that some water bodies are at a greater risk of failing the objectives due to the magnitude of the pressure and / or the degree of sensitivity of the body of water. Such water bodies may warrant more urgent implementation of the Programme of Measures.

The SWRBD was tasked with providing a basis for prioritising measures and

water bodies to achieve the objectives of the Directive. 3.8 Task 7 Development of SIMCAT Model for SWRBD

Catchment predictive modelling is a recognised means of combining impacts with pressures. The WFD Common Implementation Strategy (CIS) Guidance Document No. 3 identifies ‘SIMCAT’ as a useful tool in this regard. While it had been used successfully in other countries it was not clear that sufficient data or the right type of data were available in Ireland to run SIMCAT. Therefore, the SWRBD was tasked with reporting on the benefits or otherwise of SIMCAT as a tool in the implementation of the Programme of Measures.

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4.0 MEASUREMENT AT WASTE WATER TREATMENT PLANTS

4.1 Introduction

The availability of reliable information on the volumes and characteristics of discharges from urban waste water treatment plants is essential in identifying the risk that point source discharges may pose to the objectives of achieving and maintaining Good Status in the receiving waters. Inadequate flow monitoring and sampling at waste water treatment plants dramatically reduces confidence in any assessments intended to determine the impact of point source discharges on the quality of receiving waters. As a consequence this affects the selection of correct measures to be included in the RBMPs.

In order for Local Authorities to monitor effluent discharges and to provide the

information required to be submitted to the EPA it is necessary to have in place at waste water treatment plants means to obtain the required information as well as the expertise and resources to carry out the required sampling and testing.

The project team carried out a review of the information compiled by the EPA

from the returns from Local Authorities to the EPA concerning discharges from urban waste water treatment plants during 2003. The 2003 data was the most current published data available to the project team at the time of the review. From the review of the data it was apparent that the extent of information and the quality of the data varied widely across the Local Authorities. The review suggested that the Local Authorities may not have the means to provide this information. The project team instigated an investigation to determine the sources of the information and the possible reasons for the deficit in information provided by some Local Authorities.

The investigation sought information to determine the status of flow

measurement and sampling facilities at urban waste water treatment plants. This information would be useful to determine the confidence in the data report on flows and loads discharged from waste water treatment plants. It would also highlight and deficiencies in equipment available to Local Authorities to allow them to comply with existing legislation and Regulations.

The full report on the investigation into the sampling and measurement

equipment available at urban waste water treatment plants is presented in Volume 2 – Appendix A. The following is a summary of the background and the results of the investigations.

4.2 Background

4.2.1 Existing Regulatory Requirements / Guidance

The Urban Waste Water Treatment Regulations, S.I. Nr. 254 of 2001, as amended by S.I. Nr. 440 of 2004, places responsibility on Water Services Authorities to provide treatment of urban waste water, to undertake monitoring and to transmit the results of monitoring to the EPA. The monitoring requirements make reference to the type of sample, the frequency of sampling and the locations to be monitored.

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In 1996 the EPA published a handbook for use by Water Services Authorities

on the implementation of the Urban Waste Water Treatment Regulations. The handbook sets out recommendations concerning the monitoring of inlet and outlet flows from urban waste water treatment plants.

The report of the EPA’s Office of Environmental Enforcement “ Urban Waste Water Discharges in Ireland – A Report for the Years 2002 and 2003” makes recommendations for the sampling at urban waste water treatment plants which go beyond the requirements of the Regulations.

4.2.2 Water Framework Directive

The Water Framework Directive (Annex II, Section 1.4 - Identification of

Pressures) requires Member States to collect and maintain information on both the type and the magnitude of significant anthropogenic pressures including discharges from waste water treatment plants. The EPA Water Framework Directive Monitoring Programme highlights the importance of integrating the monitoring of water bodies with the ‘end-of-pipe’ compliance monitoring…. “It is important that the ‘ambient’ monitoring required by the WFD – where

samples are taken from natural waterbodies – is tightly integrated with end of

pipe monitoring especially in relation to assessing the effectiveness of Programmes of Measures.” This places a greater emphasis on the necessity of monitoring data from waste water treatment plants.

4.3 Review of the 2003 Waste Water Returns

The primary source of information on discharges from urban waste water

treatment plants resides in the data compiled by the EPA from the returns received from Local Authorities submitted in compliance with Article 10(2) of the Urban Waste Water Treatment Regulations.

The Project Team reviewed the information contained in the 2003 returns and

identified that an information gap exists concerning the records on the average daily flows and effluent characteristics. The main findings were as follows:

- 29.4% of waste water treatment plants have a flow monitor on the inlet - 18.3% of waste water treatment plants have a flow monitor on the

outlet - Average daily flow records were provided for 182 of the total number

of 545 plants (33.4%). It is interesting to note that some Local Authorities reported flow information

for waste water treatment plants where there is no flow device installed at the inlet or outlet of the works. It is assumed that estimates of flow are reported in such circumstances.

The report by the Office of Environmental Enforcement indicates that, of the

3,811 outflow samples taken in 2003, 54% were grab samples. In addition 66 of the 126 plants (52%) with a population equivalent greater than 2000 did not carry out the required frequency of sampling.

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4.4 Scope & Methodology

4.4.1 The objective of the investigations was to compile an inventory of flow

monitoring and sampling equipment available at WWTPs. The methodology for the collection of this information involved the circulation of a questionnaire to all local/sanitary authorities. Details of the questionnaire and the responses received are provided in Appendix A, Volume 2.

The questionnaire and covering letter were circulated in February 2006 to

relevant officers in each of the 35 Water Services Authorities. The questionnaire requested information on flow monitoring and sampling facilities at wastewater treatment plants including information on the following:

• Presence or otherwise of inlet and outlet flow monitors. • Presence or otherwise of inlet and outlet sampling equipment. • Plant Population Equivalent. • Flow Meter Type (e.g. V-notch weir, flume). • Degree of Automation (e.g. by SCADA – system control and data

acquisition). • Status of flow monitors and sampling plant (e.g. functioning, calibrated). • Source of flow measurement (e.g. measured, estimated). • Sampler Type (e.g. composite, time averaged, flow proportional).

In order to facilitate the completion of the questionnaire, the information contained in the 2003 Urban Waste Water Treatment Returns was included for each Water Services Authority for verification and/or amendment.

The questionnaire was made available as an electronic file from the project

website, www.swrbd.ie and was also sent by email if requested. The completed questionnaires were returned in electronic format by email to info@swrbd.ie.

4.5 Analysis of the Information Received

4.5.1 Summary A summary of the information received through the questionnaires is given in

Table 4.1 below. Reference to a sampler means equipment capable of obtaining a time averaged or flow proportional sample. Full details of the information provided in the questionnaires are provided in Volume 2, Appendix A.

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Table 4.1 - Summary of Availability of Flow Monitoring and Sampling

Equipment (2006)

Plant Size

(P.E.)

Total

Nrs.

With Inlet

Flow Monitor

With

Outlet Flow

Monitor

With No

Flow Monitor

With

Inlet Sampler

With

Outlet Sampler

With No

Sampler

> 50,000 10 6 6 4 6 6 4 > 10,000 to < 50,000 44 38 29 5 31 30 11

> 5,000 to < 10,000 40 32 25 7 22 30 10

> 2,000 to < 5,000 81 52 38 22 27 34 45

> 1,000 to < 2,000 110 35 26 65 18 28 77

< 1,000 255 52 30 185 28 57 187 Total 540 215 154 288 132 185 334

% of Total 40 29 53 24 34 62

4.5.2 Outlet Flow Monitoring & Sampling The survey indicates that for treatment plants with a PE greater than 10,000, 19

out of 54 (35%) waste water treatment plants do not have a flow meter on the outlet and 18 out of 54 (33%) waste water treatment plants do not have an automatic sampler on the discharge.

For treatment plants in the range 2,000 – 10,000 p.e. 58 (49%) of the 121

plants that responded to the questionnaire do not have a flow meter on the outlet and 57 (47%) of the 121 plants do not have an automatic sampler on the discharge.

The information on plants >1,000 to <2,000 p.e. indicates that 84 (76%) of 110

plants in this bracket do not have an outlet flow monitor and 82 (75%) of the 110 plants do not have an automatic sampler on the outlet.

The information on plants less than 1,000 p.e. indicates that 225 (88%) of the

255 plants do not have an outlet flow monitor and 198 (78%) of the 255 plants do not have a automatic sampler on the outlet.

4.5.3 Inlet Flow Monitoring & Sampling For treatment plants with a p.e. greater than 50,000, 4 (40%) out of the 10

wastewater treatment plants that responded to the questionnaire do not have a flow meter on the inlet and 4 of the 10 (40%) plants do not have an automatic sampler on the inlet.

For treatment plants ranging in size from 10,000 to 50,000 p.e., of the 44 plants

that responded to the questionnaire 6 (14%) do not have a flow meter on the inlet and 13 (30%) do not have an automatic sampler on the inlet.

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For treatment plants in the range 5,000 – 10,000 p.e. 20% or 8 of the 40 plants do not have an inlet flow meter while 45% or 18 of the 40 plants do not have an inlet automatic sampler.

For treatment plants in the range 2,000 – 5,000 p.e. 35% or 29 of the 81plants

do not have an inlet flow meter while 67% or 54 of the 81 plants do not have an inlet automatic sampler.

For treatment plants in the range 1,000 – 2,000 p.e. 68% or 75 of the 110 plants

do not have an inlet flow meter while 84% or 92 of the 110 plants do not have an inlet automatic sampler.

While for treatment plants <1,000 p.e. 80% or 203 of the 255 plants do not

have an inlet flow meter while 89% or 227 of the 255 plants do not have an inlet automatic sampler.

4.5.4 Maintenance

The information received from the questionnaire survey indicates that whilst flow measurement equipment may be in place, in some instances the equipment is no longer functional due to lack of maintenance.

There are a total of 540 WWTPs reported on in the 2003 wastewater returns

with varying degrees of treatment applied to the waste water from the agglomerations serviced by the treatment plants. The information received from the questionnaires indicates that only 17% have a flow measuring device for waste water which has been calibrated in the last two years. Further analysis of the information shows that for agglomerations of 2,000 p.e. or greater, 45 out of 175 or 26% have a calibrated flow measuring device.

4.6 Conclusions

4.6.1 Requirements for flow monitoring and sampling at waste water treatment

plants are stated in the Regulations concerning urban waste water treatment, S.I. Nr 254 of 2001. Local Authorities have responsibility for monitoring under the Regulations.

4.6.2 The information contained in the 2003 EPA, Urban Waste Water Treatment

returns indicates that the requirements of the 2001 Regulations are not being fully met. The conclusions of the EPA Report on Urban Waste Water Discharges in Ireland for 2002 and 2003 states that “Sampling of discharges is

in many cases inadequate and not in compliance with the requirements of the UWWT Regulations. This requires immediate attention by many local

authorities.”

4.6.3 The information obtained from the questionnaire survey indicates that flow

monitoring and sampling equipment is not available at many waste water treatment plants to provide the information required by the EPA neither is this sampling equipment in place to obtain time averaged or flow proportional composite samples required by the Regulations. From the review of the information described in Section 4.5 above, 75 waste water treatment plants with a population equivalent equal to or greater than 2,000 do not have facilities to collect flow proportional or time averaged samples from the outlet

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of the plant. It is assumed that information from these 75 plants is the result of the analysis of grab samples. This does not fulfil the requirements of the 2001 Regulations.

4.6.4 The EPA Report on Urban Waste Water Discharges in Ireland 2002/2003

makes recommendations for monitoring beyond those in the Regulations. The EPA recommend that monitoring should be carried out for waste water treatment plants with capacities of 500 p.e. or greater.

4.6.5 Notwithstanding the apparent lack of monitoring equipment, information on

flows and analyses of composite samples have been reported for wastewater treatment plants where equipment is not available. It may be the case that estimates are provided for the flows and/or that outside laboratories are contracted to obtain and analyse composite samples.

4.6.6 Information requested in the questionnaires was not provided in all cases. It is

therefore concluded that the information is not readily available. 4.6.7 It is clear from the Report of the Office of Environmental Enforcement that

Water Services Authorities are not complying with the requirements of the Urban Waste Water Treatment Regulations both in terms of the type of sample required and the frequency of sampling. There is an onus on Water Services Authorities and their regulator, the EPA, to ensure compliance with the Regulations. The public perception of lack of enforcement for non-compliance must be addressed. The Waste Water Discharge (Authorisation) Regulations, 2007 provide the EPA with stronger regulatory powers to require WWTP discharges to meet the required standards.

4.6.8 The maintenance of flow monitoring equipment is reflected in the frequency of

calibration. Only 17% of wastewater treatment plants have reported having a flow meter which has been calibrated in the last two years. This puts into question the accuracy of flow records.

4.6.9 The absence or unreliability of flow and sampling information from urban

waste water treatment plants:

• Undermines the ability of Water Services Authorities to comply with their responsibilities under the Urban Waste Water Treatment Regulations to report to the EPA.

• Makes it impossible to measure the cost effectiveness of wastewater

treatment facilities. • Makes it impossible to plan development within catchments in the most

effective way. The magnitude of the pressure and its consequent impact on the receiving water cannot be assessed.

• Will limit the EPA monitoring programme in assessing the effectiveness of

POMS (linking end of pipe sampling with waterbody sampling). • Might lead to European Commission action and judgements against Ireland

and subsequent imposed fines.

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• Leads to lack of public confidence in the ability of Water Services Authorities to manage its water services assets.

• Reflects ineffective asset management.

4.7 Recommendations

4.7.1 The following recommendations are considered to be the minimum acceptable

arrangements to ensure adequate flow monitoring and sampling equipment is in place at urban waste water treatment plants to comply with the requirements of the Urban Waste Water Treatment Regulations and to comply with the recommendations of the EPA as set out in the EPA’s Handbook for Local Authorities (published in 1996) on the implementation of the Regulations and in the EPA Report for 2002 – 2003 on Urban Waste Water Discharges in Ireland.

4.7.2 Flow Monitoring

• All WWTPs with a capacity greater than 2,000 p.e. to have continuous inlet and outlet flow monitoring and recording equipment with a means to estimate overflow volumes. Inlet or outlet monitoring only is acceptable solely in the case that there is no overflow.

• All WWTPs with a capacity of 1,000 – 2,000 p.e. to have continuous outlet

flow measurement and recording. Where such plants have overflows to the receiving water, inlet flow measurement or a means to record overflow volumes to be provided.

• For WWTPs with a capacity less than 1,000 p.e. estimates of flow based on

domestic population contributing can be taken unless there is significant licensed discharges in which case a flow meter shall be installed on the outlet. All new WWTPs to have a facility to measure outlet flows.

4.7.3 Sampling • All WWTPs with a capacity greater than 10,000 p.e to have fixed

refrigerated flow proportional samplers at both inlet and outlet. • All WWTPs with a capacity 2,000 – 10,000 p.e. discharging to designated

Sensitive Areas (under the Urban Wastewater treatment Regulations, 2001 – 2004) to have fixed refrigerated flow proportional samplers at both inlet and outlet.

• Water Services Authorities should maintain at a suitable location sufficient

portable samplers for use in the sampling of waste water from plants with a capacity less than 10,000 p.e. These samplers should be capable of obtaining flow proportional samples. Time average samples are acceptable for plants less than 1,000 p.e. where an automatic means of measuring flows has not been provided.

• Grab samples may be used for plants less than 500 p.e. The frequency of

sampling shall be determined by Water Services Authorities taking into

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consideration the risk to the quality in the receiving waters and the scale of development occurring within the catchment of the collection system.

4.7.4 Operation and Maintenance • The frequency of sampling stated in the Regulations should be considered

the minimum requirements. Water Services Authorities should put in place more frequent monitoring programmes taking into consideration the capacity of the plant and the assimilative capacity of the receiving waters.

• Where portable unrefrigerated samples are used procedures for preserving

sample integrity should be put in place. These should be consistent with the recommendations contained in the EPA Handbook for Urban Waste Water Treatment. Additionally sampling / sample preservation techniques used should be consistent with the recommendations of ISO 5667 series of publications on Water Quality.

• All Water Services Authorities to have in place a maintenance programme

for the calibration of flow measurement and sampling equipment as part of an overall Performance Management System. A PMS was developed by the Water Services National Training Group in 2002 for Design Build Operate (DBO) WWTP developments, this was web enabled in 2007 to facilitate ease of use by Water Services Authorities.

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5.0 CHARACTERISTICS OF URBAN WASTE WATER

5.1 Introduction

The pollution loading resulting from the discharges from urban waste water treatment plants has traditionally been defined in the context of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Suspended Solids (SS), Nitrogen and Phosphorus. However, it is recognised that urban waste water contains chemical substances other than the traditional parameters used to define the pollution loading. The implementation of the Water Framework Directive will introduce a new classification system for waters which will take account of the chemical and biological status of the water body. Where a water body status is classified as less than good it will be necessary to determine the causes and to implement measures to achieve Good Status. The SWRBD undertook an investigation into the characteristics of urban waste water in order to determine whether point source discharges from urban waste water treatment plans contained chemical substances, and in particular priority pollutants, at concentrations which would put the chemical or biological status of the receiving waters at risk.

The investigation was conducted in two parts. The first part involved a desk top study of existing literature and monitoring data of effluent from urban waste water treatment plants. The second part involved field sampling and analyses at selected waste water treatment plants.

There are other aspects of the characteristics of wastewater which are not

addressed in this report. One is the use of under sink food waste disintegrators which may lead to an increase in the BOD and nutrient concentrations of wastewater. A second is the high level of fats, oils and grease concentrations which have been recorded in many sewerage schemes. Research is being carried out in Ireland and abroad by others on these subjects

5.2 Background

There are upwards of 840 point source discharges from municipal waste water treatment plants throughout the country (approximately 660 of which discharge to rivers/lakes). A number of these discharges occur into waters which are less than satisfactory status (Q4) as defined by the EPA biological monitoring programme. In some circumstance the discharge from the waste water treatment plant is known to be the primary cause or a significant contributor to the unsatisfactory status. The EPA monitoring programme defines the biological status of the water according to an established classification system. The discharges from urban waste water treatment plants are regulated by the provisions of the Urban Waste Water Regulations which stipulate discharge standards in the treated effluent in the context of COD, BOD, SS, nitrogen and phosphorus depending on the size of the agglomeration served by the treatment plant and the location of the discharge. However, urban waste water contains chemical parameters in addition to those cited in the Regulations. Waste water treatment plants can

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receive contributions from commercial and industrial activities located within the catchment, which can further add to the complexity of the characteristics of the treated effluent. Furthermore, some waste water treatment plants receive landfill leachate which may further change the effluent characteristics.

5.3 Part 1 - Desktop Study

5.3.1 Existing Literature (WIR Study)

A major research study was carried out in the UK on the presence and origins of priority hazardous substances in waste water by Water Industry Research Ltd. (WIR) between 1998 and 2004. A four volume report1 was produced on the basis of this research. The contents of the report included the identification of the source of pollutants in the sewerage catchments; a screening study and literature review; research into pollution pathways from surface water drains and CSOs; and identification of treatment options and potential costs.

The WIR study involved the sampling and analysis of crude sewage entering

30 wastewater treatment plants in the UK. Approximately 45 determinants (or groups thereof) were included in the analyses. This included those parameters listed as priority substances under Article 16 of the WFD, substances for which limit values have been set under the Dangerous Substances Directive and substances listed in the EC Working Document on Sludge. An Environmental Quality Standard (EQS) value for each priority substance was selected based on the lowest EQS set by either the draft EC limits or the existing UK limits. The study highlighted the limitations of current analytical technologies in the identification of priority substances as frequently the EQS was lower than the limit of detection.

The WIR study made the following observations and conclusions: Heavy Metals

Heavy metals were detected at all wastewater treatment plants included in the study. Cadmium, copper, lead, nickel, and zinc were detected in the majority of the works with mercury and chromium being detected to a lesser extent. The study indicated that heavy metals are present in concentrations of potential concern. The draft European Community (EC) EQS for cadmium, lead and nickel is an order of magnitude lower than the concentrations found entering treatment plants. Solvents

The concentrations of the various substances classified as solvents varied

widely between plants. There is widespread use of these compounds as degreasing agents and solvents which contributes to their presence in raw wastewater. Dichloromethane and trichloromethane were found to be present in

1 Volume 1 - Identification of the Source of Priority Substances in Sewerage Catchments Volume 2 - Screening Study and Literature Review of Quantities in Sewage, Sludge and Effluent Volume 3 - Water Drains and Intermittent Discharges from Sewer Network Volume 4 - Treatment Options and Potential Costs

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almost all of the wastewater sampled from the inlet of the 30 plants. High concentrations of dichloromethane were attributed to sample contamination. Substances present to a lesser extent were trichloroethane, tetrachloroethane, benzene and 1,2 dichloroethane. Carbon tetrachloride was not detected at any works. These are extremely volatile compounds; a high level of degradation would be expected as they pass through the treatment works resulting in low concentrations in the sludge and final effluent. Combustion by-products PAH, PCBs and dioxins

Polycyclic aromatic hydrocarbons (PAHs) were detected at the majority of treatment plants sampled. Their presence was primarily attributed to inputs from petroleum sources rather than from combustion sources. They would therefore be expected to be present in road runoff. The absence of data regarding the concentrations of PAHs in the final effluent was evident from the literature review carried out as part of the study. The PAHs most commonly detected in the sampled plants were acenaphthalene, fluorene, and phenanthrene.

Of the polychlorinated biphenyls (PCBs) analysed for only one (PCB153) was

detected at two of the works. The use of PCBs is now banned. However they are persistent in the environment and as a result may be found in the influent. Recent data indicates that their concentration in sewage sludge in the UK is unlikely to exceed the EC limit of 0.8mg/kg.

Dioxins were not measured in the study due to high cost of analysis. However

a literature review was undertaken which indicated the presence of dioxin/furan concentrations in a minority of sludges in the UK that would exceed the proposed EC limit. It is expected that dioxin concentrations in the environment will decrease over time due to the restrictions imposed on the source chemicals.

Other Organics

Linear alkylbenzene sulphonates (LAS), Di (2-ethylhexyl) phthalate (DEHP)

and Nonyl phenol ethoxylates (NPEs) were detected in all of the 30 treatment plants included in the WIR study. These substances are used widely in household products and environments; their presence would therefore be expected in the sewage influent. LAS are not known to bioaccumulate to a great extent in plants or animals. There are concerns regarding the endocrine disrupting properties of NPEs and as a result their voluntary removal from the market is already occurring. The need for further study into the primary sources of these substances and their concentrations in the final effluent was identified in the WIR study.

Pentachlorophenol (PCP), hexachlorobutadiene (HCBD) and C10-C13

chloroalkanes were not found in any of the treatment plants sampled. Octyl phenols were not found in any of the plants included in the study.

However the limit of detection (LOD) was higher than the EQS. Therefore further investigation is required in order to determine the presence or absence of Octyl phenols in the influent.

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Pesticides

Of the 14 pesticides included in the WIR study, only Tributyltin (TBT) was

detected above the LOD. Many of the substances tested for are now banned in the UK and it would therefore be expected that they would not be present in the influent. It should be noted however that pesticide/biocide use is seasonal and further investigation is required on that basis. Chlorobenzenes

Substances were not detected above the LOD in almost all cases. Chlorobenzenes are not expected in the effluent as they were withdrawn from use a number of years ago.

5.3.1.1 Conclusions & Recommendations: The WIR study confirmed that raw wastewater entering urban waste water

treatment plants contains substances which have the potential to impact on the chemical and/or ecological status of the receiving waters. However, the study indicated the need for further research to determine the fate of such substances in treatment processes and recommended that further investigations be carried out in accordance with the following criteria:

• Further research should be carried out on substances/groups that have

been identified in more than 10% of WWTP influent at concentrations of

potential concern in light of existing or proposed quality standards in

either effluent or sludge waste streams.

• Substance groups recommended as priorities for further research are:

heavy metals, solvents (in particular trichloromethane, trichloroethane,

tetrachloroethene and dichloromethane), PAHS, DEHP, NPs and LAS.

• Substances/groups that were not detected in any samples, for which the

LOD was achieved or any positive detections in influent were close to or

lower than current UK EQS and draft EC EQS and for which seasonal use is not expected, are recommended to be excluded from future research.

Substances meeting these criteria are trichlorobenzene,

hexachlorobutadiene, and the banned pesticides DDT, the 'drins and

HCH.

• There were a number of groups of substances that were detected in a small

number of samples or whose presence at significant concentrations cannot

be discounted on a precautionary basis. These groups are recommended

for inclusion for future research subject to cost-benefit analysis. These groups of substances are summarised below:

- Substances not detected in the screening study but likely to have a seasonal

use i.e. Pesticides - alachlor, atrazine, chlorfenvinphos, diuron,

endosulfan, isoproturon, simazine, trifluralin.

- Substances detected in <15% samples or whose presence could not be ruled out because the LOD was achieved was higher than current of

proposed EQS: benzene, brominated diphenyl ethers, 1-2 dichloroethane,

C10-13 chloroalkanes, pentachlorophenol and tributyltin

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5.3.2 Desk Top Study – Existing Monitoring Data (Ringsend)

The National Dangerous Substances Working Group undertook a study of the influent and effluent at the Ringsend WWTP as part of a national monitoring programme established to identify the presence of Dangerous Substances in receiving waters.

As part of this MIR study the results of the national study pertaining to

Ringsend were compared to the "draft" EQS values as set out under the Water Quality (Dangerous Substances) Regulations 2001, and also to EQS values set in the UK and to the draft EC EQS values. A summary of the findings are outlined below under the various parameter group headings: Metals

Metals detected in the effluent from Ringsend WWTP included boron, zinc, antimony, cobalt, nickel, uranium , cobalt, copper, arsenic, selenium, titanium, lead, tin, molybdenum, mercury and vanadium. Zinc and antimony were present at concentrations exceeding the EQS values.

Pesticides

A significant number of pesticides were detected in the effluent from Ringsend

WWTP. Pesticides which were present in concentrations exceeding the "draft" EQS include diuron, isodrin, epoxiconazole (triazole), glyphosate, alachlor, dieldrin, diflubenzuron and maneb/ zineb/ thiram/ mancozeb.

Anions and sum-parameters

Anions and sum parameters detected in the effluent from Ringsend WWTP included fluoride, chloride and cyanide. Chloride was present in concentrations exceeding the draft EC EQS values. Cyanide was present in 29% of the samples at concentrations less than the EQS.

Hormone-disrupting compounds

A number of hormone-disrupting compounds were detected in the effluent from Ringsend WWTP. Hormone-disrupting compounds which were present in concentrations exceeding the draft EQS values include: Di-n-butylphthalate, Di-(2-ethylhexyl)-phthalate (DEHP), Nonylphenol ethoxylates, 4-tert-octylphenol, sum diphenyl ether/ pentabromo derivates and tributyltin. A number of additional hormone disrupting compounds were detected in the samples which have no corresponding EQS value as follows: C10-C13 (PCA), Bisphenol-A, Butylbenzylphthalate, tetrabromobisphenol-A, Diisononylester DINP and nonylphenols.

Volatiles

Volatiles which were detected in the effluent from Ringsend WWTP but not exceeding the "draft" EQS include: Trichloromethane, Dichloromethane, O-xylene, Toluene, P,m-xylene, 1,1,1-trichloroethane, 1,2-dichloroethene, 3-chloropropene (akylchloride), ethylbenzene, isopropylbenzene, tetrachloromethane, trichloroethene, and MTBE.

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PCB, -phenol, -benzene

PCB, -phenol, -benzene which were detected in the effluent from Ringsend

WWTP but not exceeding the "draft" EQS include: Trichlorophenols, 2,4/2,5-dichlorophenol and dichlorobenzenes, Sum PCB and PCB28, 4-chlor-3-methylfenol, mono-chlorophenol, PCB118, and PCB52.

Polycyclic aromatic hydrocarbons (PAH)

Polycyclic aromatic hydrocarbons which were detected in the effluent from Ringsend WWTP but not exceeding the "draft" EQS include: Fluoranthene, Napthalene, Anthracene, Benzo[a]pyrene, benzo[b]Fluoranthene, Indeno[1,2,3-cd]pyrene.

Nitrated aromatics and amines

Polycyclic aromatic hydrocarbons which were detected in the effluent from Ringsend WWTP but not exceeding the "draft" EQS include: Dimethylamine, and Diethylamine.

5.3.2.1 Conclusions & Recommendations:

The monitoring of the effluent from the Ringsend waste water treatment plant has provided further evidence that effluent from urban waste water treatment plants can contain substances at concentrations above the Environmental Quality Standards required in the receiving waters. The impacts of treated waste water on the receiving waters will depend on the sensitivity of the receiving waters to such discharges. The Ringsend waste water treatment is probably unique in Ireland given that it is the largest treatment plant in the country and it serves a catchment with contributions from a vast range of commercial and industrial activities. However, the results do highlight the need for further research in this area.

5.4 Part 2 - Field Sampling and Analyses

5.4.1 General

The desktop research carried out in Part 1 indicated that substances are present in untreated wastewater entering waste water treatment plants and treated effluent discharges from the plants at concentrations which may pose a risk to the status of the receiving waters. In order to test the reported data in a representative Irish context, a programme of field testing was carried out at a number of treatment plants throughout the country. The field tests were carried out in two phases.

Phase 1 of the field tests set out to confirm or otherwise the presence of

substances identified in the desktop study at nine wastewater treatment plants representing various types of communities served (i.e. urban / rural) and sizes of treatment plant (1,200 PE – 1.5M PE). Analyses were also carried out on samples of the receiving waters to determine if there were any recognisable impacts on water quality resulting from the discharge.

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Phase 2 attempted to determine if waste water treatment plants treating leachate posed a greater risk to water quality status due to the substances contained in leachate which may not be otherwise present in typical urban waste water effluent.

The extent of the Phase 1 and Phase 2 field tests were limited by both time

constraints and budgets. The results in many cases were inconclusive and in some cases contradictory. Further analysis over an extended period will be required to test the consistency and validity of the data.

5.4.2 Phase 1 Field Tests

The presence of priority pollutants was investigated by monitoring at the following urban waste water treatment plants: Bandon, Buttevant Carrigrenan (Cork City) Castleisland Charleville Moate Tullamore Ringsend (Dublin) Roscommon Samples were taken in November 2006. At each location a grab sample of treated effluent and a sample of sludge were taken. At six of the WWTPs (Buttevant, Castleisland, Charleville, Moate, Tullamore and Roscommon) grab samples of the receiving were taken upstream and downstream of the outfall location. The analyses of the samples included the general chemical parameters ubiquitous in urban wastewater. The waste water treatment plant at Tullamore receives landfill leachate for processing. The analyses of the samples taken from this plant and from Castleisland WWTP, which does not receive leachate, were analysed for 26 additional parameters found in landfill leachate. In addition to chemical monitoring at the selected sites, a biological Q-assessment was conducted to determine the status of the macroinvertebrate community living in the receiving watercourses. The Q-assessment followed the biotic index system used by the Environmental Protection Agency (EPA) in their ongoing monitoring of biological quality in Irish rivers. This assessment was intended to identify possible impacts on the receiving waters as a result of the discharge of treated effluent from municipal WWTPs. The chemical sampling and analyses were carried out by Bord Na Mona. The biological Q-assessment was conducted by the Aquatic Services Unit, University College Cork.

5.4.2.1 Results of Phase 1 Field Tests:

A full record and description of the results of the Phase 1 field tests is provided in Appendix B of Volume 2

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General Parameters

The results of the analyses of general parameters are typical of what would be

expected. The only result of note was the relatively high concentration of ammonia found in the sample taken from the effluent from the Tullamore WWTP – 23mg/litre. The Tullamore treatment plant is designed for nitrogen removal but it receives leachate which may be responsible for the higher than expected ammonia level.

Metals

Metals investigated for under the study were confirmed present at all nine waste water treatment plants. Generally the concentrations found were at or below the Environmental Quality Standards (EQSs) required in the receiving waters with the following exceptions: Aluminium concentrations in the effluent ranged from <2 to 1,510 µg/l, with 6 out of 9 samples exceeding the EQS required for the receiving waters. The concentration of Zinc exceed the EQS value in the effluent sample from the Moate WWTP. (156ug/l versus 100ug/l)

Anions

Selenium and Chloride were generally detected below the EQS value. The one exception is the concentration of Selenium in the effluent sample from the Tullamore WWTP. The concentration was measured as 5ug/l which is equivalent to the Fresh Water chronic level.

Pesticides

Pesticides were not detected in the samples taken during November 2006. Their use is seasonal and therefore the results of the analyses are not unexpected.

Other Organics, Solvents, and Volatiles

The samples were analysed for these parameters and no significant differences were found between Tullamore and Castleisland WWTPs. All parameters were below their respective EQSs with the exception of vinylchoride and 2-ethyltoluene for which there are no EQSs available.

Polycyclic Aromatic Hydrocarbons (PAH)

All results were below the EQS values with the exception of Fluoranthene concentration in the effluent sample from the Buttevant WWTP. (0.13ug/l compared to an EQS of 0.020 ug/l)

Polychloro -biphenyls, -phenols, -benzenes

The concentrations of these substances in the effluent was found to be lower than the EQS concentrations where there are published values for same. In general the levels of PCBs where slightly higher in the effluent from Tullamore

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WWTP, which receives leachate, compared to the concentrations found in the effluent from Castleisland.

Hormone Disrupting Compounds

Di-(2-ethylexyl)-pthalate (DEHP) was detected at all WWTPs at levels which generally exceed the EQS, as indicated in Table 5.4.1. The analysis of water samples taken upstream and downstream of the point of discharge also confirm levels above the EQS levels. In some cases the discharge from the WWTP appears to be impacting on concentrations in the receiving waters.

Table 5.4.1 - Phase 1 Monitoring Results for Di-(2-ethylexyl)-pthalate (DEHP)*

Location Effluent

ug/litre U/S

ug/litre D/S

ug/litre

Sludge

Bandon 2.2 13

Moate 2.2 0.48 1.6 8.1

Charleville 2.1 1.1 1.3 8.7

Castleisland 3.5 .056 6.5 9.6

Roscommon 1.5 0.89 1.5 29

Buttevant 3.8 0.6 3.8 58

*EQS - 0.5ug/l in water. Biological Monitoring

A biological Q-assessment (following the Q biotic index system used by the

EPA) was also conducted for the receiving waters of each plant which discharged to a river in order to assess possible impacts resulting from the discharge of chemical pollutants present in the effluent from WWTPs. It should be noted that samples were taken in November which is acknowledged to be late in the recommended sampling season.

The Q assessment is categorised as follows in terms of pollution status:-

Q5 – pristine, unpolluted Q4 – unpolluted Q3/4 – slight pollution Q3 – moderate pollution Q2 - heavy pollution Q1 – gross pollution

The samples were taken as close as possible upstream and downstream of the

point of discharge and the results were compared against the quality status reported by the EPA for the nearest upstream and downstream official biological monitoring stations.

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A summary of the results is presented in Table 5.4.2 below. In general the results confirm the quality status reported by the EPA. The results also suggest that the biological water quality status in the receiving waters at Castleisland, Tullamore and Charleville is influenced by the discharge of effluent from the respective waste water treatment plant.

Table 5.4.2 - Results of Biological Assessment in the Receiving Waters

Sampling Site Q-Value Rating Distance EPA Q (2003)

* Distance

Buttevant upstream Q 3-4 60m Q 3 800m Buttevant downstream Q 3-4 200m Q 3-4 3,500m Charleville upstream Q 2-3 200m Q 3 2,500m Charleville downstream

Q 2 200m Q 2-3 500m

Castleisland upstream Q 4 250m Q 3-4 800m Castleisland downstream

Q 3-4 65m Q 3-4 1,800m

Moate upstream Q 2-3 50m - - Moate downstream Q 2-3 50m Q 3 80m Tullamore upstream Q 2-3 500m Q 3-4 6,500m Tullamore downstream

Q 2 3,800m Q 2 3,800m

Roscommon upstream (Juggy/Hind)

Q 3 600m Q 2 1,800m

Roscommon upstream (Rocksavage)

Q 3 1,500m Q 4 1,500m

Roscommon downstream (Hind)

Q 3 150m Q 2-3 180m

5.4.2.2 Conclusions and Recommendations (Phase 1): The samples taken during the Phase I field tests in November 2006 were for the

most part grab samples. The analyses were intended to give an indication as to the presence of substances know to be ubiquitous in urban waste water and which are known to have an impact on chemical and biological status of the receiving waters.

Much like the WIR study, the Irish field study highlighted the limitations of

current analytical technologies in the identification of priority substances as frequently the EQS was lower than the limit of detection.

It was concluded from the field test that treated effluent does contain the range

of substances reported in the WIR study. Furthermore, the results indicate that effluent from waste water treatment plants contains substances at concentrations above the EQS values required in the receiving waters and hence the potential exists to impact water quality where there is insufficient dilution available in the receiving waters.

The field tests have shown that discharges from waste water treatment plants

contain Di-(2-ethylexyl)-pthalate (DEHP) at concentrations above the EQS

* taken at closest u/s or d/s location

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values and that such discharges have caused increased concentration in the receiving waters above the EQS levels. This has implications for achieving the required quality standards.

The field tests were inconclusive with regard to the impact of treating leachate

at waste water treatment plants. There is evidence in the results of the analyses to suggest that ammonia concentrations and levels of PCBs are elevated in the effluent discharges at plants receiving leachate. However, it would not be prudent or advisable to come to this conclusion on the basis of the analysis of a single grab sample.

Resulting from the outcome of the Phase 1 field tests it was recommended that

a second phase of tests should be carried out to determine the impact of treating leachate at waste water treatment plants.

5.4.3 Phase 2 Field Tests Phase 2 field testing was carried out in July 2007 and involved the sampling

and analysis of influent, effluent and sludge from five wastewater treatment plants, i.e. Charleville, Nenagh, Tipperary Town, Castleisland and Macroom, the first three of which receive leachate for treatment. Samples from the receiving water were also analysed to determine if there was a correlation between the quality of the discharge and the ecology of the receiving water.

In the Phase 2 field tests the effluent samples taken for analysis were 24-hour

and 48-hour composite samples. Grab samples from the return sludge were also taken.

5.4.3.1 Results of Phase 2 Field Tests: The results of the Phase 2 field test are presented in Appendix B of Volume 2.

The results pose more questions than answers and this is due to the questionable nature of the laboratory reports. The reports returned a number of schedule errors and there were a number of irregular and spurious results of analysis.

General Parameters It was suspected from the Phase 1 results that high concentrations of ammonia

might be expected from waste water treatment plants treating leachate. However, this is not evident from the Phase 2 results and some of the reported results are questionable due to inconsistencies and anomalies in the reported results. This cast doubt on the validity of the results.

Metals

Inconsistencies in the laboratory results cast doubt on the validity of individual

values. However the reported effluent values were below the EQS values, this is consistent with the results from Phase 1.

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Anions

Chloride concentrations were consistently higher in effluent from plants

treating leachate but in all cases the values were well below the EQS value required in the receiving waters.

Pesticides

Pesticides were not detected in any of the effluent samples. Other Organics, Solvents, and Volatiles

These parameters were not detected at any of the plants. However there were a

number of schedule errors by the laboratory when undertaking this analysis therefore the results remain questionable.

Polycyclic Aromatic Hydrocarbons (PAH)

These parameters were below the level of detection in the samples analysed with the exception of naphthalene which was detected at one plant only at concentrations well below the EQS value.

Polychloro -biphenyls, -phenols, -benzenes

These parameters were below the level of detection in the samples analysed.

Hormone Disrupting Compounds

Tributyltin, DEHP and Di-n-butylphthalate were not detected above their respective LODs.

5.4.3.2 Conclusions and Recommendations (Phase 2):

The outcome of the Phase 2 field study has proved inconclusive with regard to determining the consequences for receiving water quality resulting from the treatment of leachate at waste water treatment plants. The level of detection for various parameters reported by the laboratory was in some instances above the EQS values. Furthermore there was a lack of confidence in some of the reported results due to inconsistencies and anomalies in the results. It is suspected that the results do not represent an accurate assessment of effluent from plants treating leachate when compared to plants which do not treat leachate. It is concluded that a more detailed investigation is required into the processing of leachate at each waste water treatment plant. It would have been expected that leachate would have increased the concentration of a number of parameters in the influent. However, this has not been detected in the analysis. The measurements of the influent BOD, COD and TOC are suspect at all plants and therefore can’t be relied upon.

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5.4.3.3 Overall Conclusions and Recommendations: Due to the poor nature of the results from the Phase 2 study, the results from the previous WIR study and the Phase 1 study could neither be validated nor contradicted. It is recommended that a more detailed investigation be undertaken to examine the potential impacts on water quality resulting from the treatment of leachate at waste water treatment plants. The duration of any further studies should be sufficient to provide a representative number of samples to draw firm conclusions on the probable impacts. Laboratory procedures and protocols should be examined before commencement and during the study to resolve any anomalies.

In future studies the quantities and source of leachate arriving at treatment plants should be determined. The procedures for processing leachate through the treatments plants should be confirmed and witnessed such that analysis of effluent samples can be taken as representative of the contribution of leachate in the loading to the treatment plant.

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6.0 POPULATION GROWTH PROJECTIONS

6.1 Introduction

Wastewater arising from human activities is the most significant contributor to

municipal effluent. Therefore, any increase in population in the area served by a sewerage scheme will result in an increased load being discharged to the waste water treatment plant. In order to achieve the objectives of the Water Framework Directive (WFD), i.e. achieve good quality status in all our waters by 2015, it is necessary to make population projections to calculate the future impact of such discharges.

6.2 Scope

Population growth projections were carried out for all catchments of waste

water treatment plants with an existing population equivalent of 300 persons or more. The target year for projections was 2015, to keep it in line with the WFD objectives. The task involved the development of a pilot methodology which would consider National Population Strategies, Census Projections, Regional and Local Plans. The pilot methodology was tested for catchments within County Cork. The purpose of the pilot study was to test the methodology and examine the transferability of the methodology to other regions. A full version of the pilot report is available in Appendix C1 of Volume 2.

6.3 Development of Methodology

6.3.1 The pilot methodology was based on a ‘Bottom up – Top down’ approach.

‘Bottom up’ refers to consideration of information contained in County Development Plans and Local Area Plans. ‘Top down’ refers to consideration of information contained in National and Regional Plans such as the National Development Strategy and Regional Planning Guidelines.

6.3.1.1 Bottom-Up Methodology

The “bottom-up” methodology estimated population forecasts for urban areas using the data and information provided at Water Services Authority and sub-Water Services Authority level, i.e., County Development Plan (CDP), Local Area Plans (LAP), Special Local Area Plans (SLAP), Town Council Plans, Strategic Plans including housing strategy, retail strategy and strategic land use (e.g. Cork Area Strategic Plan and North and West Cork Strategic Plan).

• The Census 2002 was taken as a consistent baseline population for all

settlements and urban areas. (Complete Census 2006 data was unavailable at the time of the study)

• The CDP provided projected households for the year 2011 and some

detail on County total population by 2011. It provided a distribution of households for the 31 main settlements. This was converted to populations for 2011.

• The LAPs and SLAPs provided household distribution forecasts for the

towns and key villages in each Electoral area, but not all LAPs have the

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same level of detail. This data enabled populations to be derived for many of the settlements for 2011.

• The Cork Area Strategic Plan (CASP) and the South West Regional

Planning Guidelines give forecast population ranges for Cork City and County for 2020. The upper ranges were taken as a ceiling for growth.

• Population was distributed for 2020 to the main settlements in

accordance with the distribution proportions used by the CDP for 2011. This process then received a “second iteration” to review the distribution to accord with the SLAPs, CASP and the SWRPGs for the later period 2011-2020.

• The 2015 population was estimated for each settlement as an

interpolation between 2011 and 2020. 6.3.1.2 Top Down Methodology

The top-down methodology comprised reviewing the key National and Regional policy documents in relation to spatial planning, population forecasting and distribution (as included in Table 6.1). For the purpose of the Pilot Study, this involved isolating the data relevant for the State, for the South West Region and for Cork. The principal documents referred to in Table 6.1 were produced and published at successively later dates following the publication of the National Spatial Strategy (NSS) and the Census of Population 2002. Therefore, assumptions made in 2002 have been successively revised with the publication of later reports in 2003, 2004 and 2005 as economic outlooks changed and the results of the 2002 Census were evaluated. The data quoted in the NSS and Regional Planning Guidelines are more often than not target populations or target ranges. Therefore, as analysis of the data progressed in recent years, the revised estimates made in 2004/2005 were increasingly tending towards the upper limits of the ranges quoted in 2002, while at the same time staying within the policy range.

Date Document Key Data

2002 National Spatial

Strategy

State Population 2020:

South-West Region Population 2020:

Cork Gateway 2020:

4.4 – 5.0 m 670,000-740,000 454,000

2003/ 2004

South-West

Regional

Planning

Guidelines

(RPGs)

South-West Region

Population 2020:

CASP Area 2020:

County Cork 2020:

Cork City 2020:

670,000-700,000 423,000-450,000 385,000-398,000 136,000-142,000

2003 CSO Regional Projections for

RPGs

State Population 2020: South-West Region

2020:

South-West Hubs 2020:

4.4 – 4.5 m 650,000 +20,000

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Date Document Key Data

2004 CSO Population

and Labour

Forecasts

State Population 2021:

State Population 2021

(M1F2 ):

4.803 – 5.140 m 5.070 m

2005 CSO Regional

Population Projections

South-West Region

2020: State Population 2020:

705,000 5.070 m

2005 CSO Population

and Migration

Estimates

South-West Region

2005:

State Population 2005:

609,700 4.130 m

Table 6.1 Principle Documents used in Top Down Methodology

6.3.2 Assessment of Methodology in a ‘Data Poor’ Local Authority - Mayo

Following completion of the population forecasting for County Cork, it was decided that it would be appropriate to carry out a further trial of the methodology for a Local Authority which provides less detailed disaggregated data on its future settlement policy.

County Mayo was chosen for this trial. The results of the trial are as follows:-

• County Mayo had a total of 30 Census Towns in the CSO Census Report

2002 of which 23 had a population of greater than 300.

• The County Development Plan has a well-articulated development framework including a settlement hierarchy; however it provides a limited amount of disaggregated forecast populations.

• The population forecasts to 2021 are provided at a county level only. No

further specific distribution method or prioritisation is indicated to allocate the population to the smaller towns and villages such as Local Area Plans etc.

• The development framework outlined in the CDP introduces a spatial

element into the wider socio-economic issues such as population patterns and distribution, scale and nature of activities and services. It is founded on a number of national policy documents and perspectives and has at its core the need to achieve balanced, sustainable development, social inclusion and cohesion throughout the county.

• The settlement hierarchy in Mayo is differentiated into 4 distinct types

of areas by size, function, character and role, viz: - The 3 main urban centres of Ballina, Castlebar and Westport, the

larger towns of Ballyhannis, Ballinrobe, Belmullet, Claremorris, Swinford and Crossmolina, the smaller towns such as Louisburgh, Kiltimaagh, Newport, Killala and Foxford and the villages.

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• The development framework highlights a strategic objective for each of these four types of area, which in turn provided focus for goals and objectives, the aim of which is to secure the sustainable and balanced development of the county.

• The purpose of the development framework is to define spatially a role

for each of the four types of area and to direct and enhance the growth potential of both urban and rural areas in a sustainable and balanced way. If the framework is pursued proactively it could redress the decline of rural areas, spreading the benefits derived from the strength of the urban centres and as such would reinforce and recreate the strong interdependency between town and country characteristic of Mayo in the past.

• The population projections outlined for Mayo are based on the

development framework approach with increasing growth in particular in the 3 main towns, and consolidating the larger and smaller towns to a lesser degree.

• The results of the Preliminary Census Report 2006 were used to give an

indication of the areas in which there has been a population increase since 2002 in order to guide the distribution process.

6.3 Updated Methodology

After the ‘Bottom up – Top down’ methodology was developed there were two

significant publications which were considered and resulted in a revision of the methodology. The publications are:

• Census 2006 Preliminary Report published by Central Statistics Office • ‘National Population Projections and Regional Population Targets

2006-2020’ published by the Department of the Environment, Heritage and Local Government. The document is included in Appendix C2 of Volume 2.

As the most recent CSO data (2002 and 2006) was now available a reasonably

robust projection could be made to 2015 based on the growth rate of population centres from 2002 to 2006, i.e. bottom up approach. This could then be checked against the new Regional Population Targets from the DEHLG document, i.e. top down approach.

• The projected 2015 County population figures were estimated using

two methodologies as follows (refer to Table 6.2): • The first methodology estimated the 2015 regional populations

(Border, Midlands, West, Greater Dublin Area, Mid-West, South-East and South-West) by applying a compound calculation to extrapolate the rate of increase in regional population from 2002 to 2006 onto 2015 using CSO data (refer to the section highlighted in green in Table 6.2).

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• The second methodology estimated the 2015 regional populations using the DOEHLG National population projections and regional population targets report 2006-2020 as published in February 2007 (refer to the section highlighted in blue in Table 6.2). − This report provided regional population projections for 2016 and

2020. − The 2015 regional populations were calculated assuming uniform

annual population growth between 2016 and 2020 (i.e. the annual population increase was calculated and this figure was subtracted from the 2016 figure to give an estimated 2015 regional population figure).

• The 2015 County populations were then calculated from the estimated

2015 regional populations. This was achieved by calculating the ratio of distribution of the 2006 County populations to the 2006 regional population figures and then applying this distribution to the 2015 regional populations thus providing an estimated population for each County within each region (refer to the sections highlighted in yellow in Table 6.2).

• The resulting County figures correlated well from the two approaches.

Generally the County figure from the bottom up approach was selected for inclusion in the MIR dataset unless the population exceeded the estimated County ceiling as provided by the DEHLG regional targets. In these cases the County ceiling itself was used.

• The individual town populations per County were sourced from the 2006 CSO figures. Table 6.3 shows an example of this. These figures were totalled to give the overall ‘urban’ population per County. The 2006 ‘urban’ population was subtracted from the 2006 County population (as sourced from the CSO) to provide the ‘rural’ population (refer to the sections highlighted in green in Table 6.3).

• No change in rural population was assumed between 2006 and 2015.

This ‘rural’ population was then subtracted from the projected 2015 County populations to give the estimated 2015 ‘urban’ population per County (refer to the section highlighted in yellow in Table 6.3). The 2006 town populations were examined to calculate the ratios of population distribution amongst the towns from the overall 2006 ‘urban’ figures (refer to section highlighted in blue in Table 6.3). These ratios were then applied to the estimated 2015 ‘urban’ population for each County in order to provide projected town populations (refer to the section highlighted in pink in Table 6.3).

Appendix C3 of Volume 2 shows the population projection results to 2015 for all of the population centres with a population greater than 300 on a County by County basis.

P

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Work

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of th

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pro

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latio

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Na

tion

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patia

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ata

Region

Counties

Populations 2002

Populations 2006

percentage population increase

between 2002 and 2006

Total regional population 2006

Percentage distribution of total

regional population 2006

among counties

increase in population between

2002 and 2006

Projected 2010 figures based on growth rate between 2002 and

2006

Estimated Population increase between 2006 - 2010

Projected 2014 figures based on growth rate between 2006 and 2010 using 2010 figure as base

Estimated population increase between 2010 - 2014

Percentage population increase per year (2010 - 2014)

Projected 2015 figures based on annual growth rate between 2010

and 2014 using 2014 figure as base figure

Projected 2015 Regional population

2016 Regional populations as

per Table 7 of the DOE

National population

projections and regional

population targets report

2006-2020 published February

2007

Calculated 2015 regional

populations using the DOE

2016 and 2020 projections

Finalised projected County

populations for 2015

2020 NSS Target: 5 Million.

Percentage Distribution per

Region

2020 NSS Target: 5 Million.

Population Distribution per

Region

Distribution of 2020 predicted

regional population between

counties based on 2006

percentage distribution

Galway

209,077 231,670

10.81 %

55.64

%

22593 256,704.41

25,034.41 284,444.06

27,739.65 2.44%

291,378.98

286,637.79 284,838.

36

Mayo

117,446 123,839

5.44%

29.74 %

6393

130,579.99 6,740.99

137,687.92 7,107.93

1.29%

139,464.91 136,930.51

152,260.10

West

Sligo

58,200 60,894

4.63%

416,403

14.62 %

2694

63,712.70 2,818.70

66,661.88 2,949.18

1.11%

67,399.17

498,243.05 497,224

489,721.25

66,152.96

10.21 %

511,967.66

74,869.20

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Sligo

Town Persons 2002

Persons 2006

Percentage distribution of

total town population

among indiv idual towns (2006)

Distribution of the projected

2015 total town population figure using percentage

breakdown of 2006 figure

Ballincar 510 526 1.75% 618

Ballintogher 0 182 0.60% 214

Ballisodare 853 971 3.22% 1141

Ballygawley 0 186 0.62% 218

Ballymote 981 1229 4.08% 1444

Carney 0 219 0.73% 257

Cliffoney 327 425 1.41% 499

Collooney 619 892 2.96% 1048

Coolaney 167 208 0.69% 244

Easky 211 240 0.80% 282

Grange 225 383 1.27% 450

Gurteen 250 269 0.89% 316

Inniscrone 668 829 2.75% 974

Mullaghmore 137 147 0.49% 173

Riverstown 273 310 1.03% 364

Rosses Point 774 872 2.89% 1024

Sligo Borough 18473 17892 59.39% 21016

Sligo Environs 1262 1510 5.01% 1774

Strandhill 1002 1413 4.69% 1660

Tubbercurry 1171 1421 4.72% 1669

Total 27903 30124 100.00% 35383

Sligo

Total County population 2006

Total Town population 2006

County 2006 population

figure minus the total towns

population (rural

population 2006)

Projected 2015 figure

(using DOE National

population projection data)

Projected 2015 figure minus rural

population 2006 (giv ing total towns 2015 population)

60894 30124 30770 66153 35383

Table 6.3 Worked example of the 2015 town population projections for Sligo.

6.4 Conclusion

The methodology used to determine population forecasts for all catchments of waste water treatment plants with an existing population equivalent of 300 persons or more are based on the best available data at the time of the publication of this report. The availability of the new aforementioned publications during the course of the work enabled the methodology to be updated. These projected populations were applied to the risk assessment in order to best predict the impact of population change and resulting increased pollution load up to the year 2015 on point source discharges from municipal sources.

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7.0 WATER BODIES AT RISK FROM POINT SOURCE DISCHARGES

7.1 Introduction

The primary objectives of the Water Framework Directive are to achieve ‘Good Status’ in all bodies of water by 2015 and to prevent deterioration in the status of water bodies. Human activities, which result in discharges of pollutants to bodies of water, are a pressure on the quality status of the receiving water body. Point source discharges of pollutants, such as from waste water treatment plants and industrial discharges can, in some circumstances, put at risk the achievement of the WFD objectives. It is therefore necessary to determine under what circumstances a point source discharge poses a risk to the status of a water body.

7.2 Background

The Water Framework Directive requires that an assessment be carried out of

the susceptibility of a surface water body to the pressures which have been identified from human activities. For those bodies of water identified as being at risk of failing environmental quality objectives, further characterisation shall, where relevant, be carried out to optimise the design of monitoring programmes and the Programme of Measures.

The Characterisation Report required under Article 5 of the WFD was submitted to the European Commission on 22nd March 2005. The report represents the results of a comprehensive risk assessment that was undertaken to categorise water bodies according to their risk of failing to meet ‘Good Status’ by 2015. The risk assessment was carried out using the information available at that time.

The risk assessment for point source discharges which was carried out for the

Article 5 report considered compliance with discharge standards and frequency of sampling as the basis of the risk assessment. Expert judgement was also employed. Due to the lack of data and time limitations, no account was taken of the magnitude of the discharge, nor of the assimilative capacity of the receiving waters. With the available data, it was concluded that 13.5% of water bodies were at risk of failing to achieve Good Status due to point source discharges from urban waste water treatment plants and from licensed discharges. However, there remained a degree of uncertainty as to the outcome of this assessment due to the data gaps.

The SWRBD has gathered available data relevant to the pressure which point

source discharges impose on water quality. This information includes:-

− datasets compiled by the EPA concerning information supplied by Local Authorities (Local Authority Returns)

− EPA datasets on IP(P)C licences − Local Authority datasets on licensed discharges to surface waters (Section

4 licences) . − data on the loading and capacity of waste water treatment plants. − receiving water quality monitoring data. − hydrometric data.

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− existing population data and projected population increases. − boundaries of protected areas. − high status sites.

This information has been used to carry out further characterisation of bodies

of surface water impacted by point source discharges to better define the risk posed by such discharges.

7.3 Sensitivity of the Receiving Waters

7.3.1 General The risk to receiving waters of failing to achieve ‘Good Status’ posed by a

point source discharge is related to the magnitude of the pressure (pollution load) and the sensitivity of the receiving waters to that pressure. This may be evidenced by the results of monitoring data. A discharge from a small waste water treatment plant to a small stream or river may pose a greater threat to water quality than a discharge from a larger plant to a major watercourse due to the greater dilution which may be available in the larger body of water.

The magnitude of the pressure refers to the pollution loading discharged at the

point source. For urban wastewater treatment plants the magnitude of the pressure is influenced by the following:-

- The loading entering the treatment plant (existing and future). - The degree of treatment applied (primary, secondary, tertiary). - The capacity of the treatment plant. - The operation and maintenance of the plant. For IP(P)C and Section 4 licensed discharges, the magnitude of the pressure is

stated in the licence consents The sensitivity of the receiving waters is influenced by the following:- - Available dilution (flow) to assimilate the pollution loading.

- Sensitivity of aquatic species to water quality as is demonstrated by impact data such as the existing “Q” rating.

- Background chemical/physical concentrations. The magnitude of the pressure coupled with the sensitivity of the receiving

waters determines the risk of failing to achieve ‘Good Status’. Some water bodies are more sensitive than others and this may relate to their

special importance such as designated Protected Areas and High Status Sites. Point source discharges may pose a greater risk to these areas than would be the case if the designation did not apply. These are examined and criteria have been established to define the risk.

In the following sections, the evidence from impact data is examined to

determine if point source discharges are impacting water quality. Also, factors which influence the magnitude of the pressure and the sensitivity of the

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receiving water body are examined. A risk assessment has been carried out and the results are reported.

7.3.2 Impact Data Existing monitoring data can provide evidence of the impacts of point source

discharges. Where the water quality in the receiving waters is known to be less than ‘Good Status’, it can be concluded that the body of water is impacted by human activities (from either point or diffuse sources). The activities which are impacting the water body may involve direct or diffuse discharges. Further interrogation of the data may provide evidence that the impact is more likely from a point source discharge than a diffuse source or vice versa.

The existing status of the receiving water body at the nearest monitoring station

downstream of a point source discharge was identified from the EPA report on river water quality, 2005. Where the downstream Q-value was less than 4, the receiving water body was considered to be impacted by the point source discharge. However, as the distance downstream of the monitoring station increases, the greater the uncertainty as to the significance of the impact of the point source discharge.

The criteria used to identify water bodies at risk from point source discharges,

based on impact data, is as follows:- - Deterioration in Q-status between u/s and d/s where the d/s monitoring

station is within 3 km of the point of discharge. - Q-status downstream is less than 4 and the monitoring station is less than 3

km downstream of the point of discharge. - Historical deterioration between u/s and d/s results in Q-status (i.e., Q4.5 to

Q4) where the u/s and d/s monitoring stations are within 3 km of the point of discharge.

All water bodies downstream of a point source discharge for which the above

criteria apply are deemed to be at risk. The results of this assessment are presented in Appendix E of Volume 2.

7.3.3 Magnitude of the Pressure The magnitude of the pressure for the purposes of this study is defined as the

pollution loading expressed in terms of the volume of the discharge and the characteristics of the discharge taken in combination.

The volume of the discharge at each point source discharge from urban waste

water treatment plants was, in the first instance, derived from the information reported in the 2005 Local Authority returns to the EPA. Where no flow information was reported, the flow discharging from the waste water treatment plant was estimated based on the reported PE of the plant and allowing 250 l/h/day of wastewater.

Likewise, information on the characteristics of the discharge can be derived

using the same sources. For each discharge the average concentration of BOD

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in the discharge was calculated from the information provided in the 2005 returns. The average concentration was multiplied by the reported flow giving the total mass emission in kg/day. Where no information on BOD in the discharge was available a default concentration of 25mg/litre was taken. Because of the data gaps and inconsistencies in reported data this method was recognised as being indicative only.

The pollution loading from licensed discharges was taken as the allowable

discharge volumes and quantities as set out in the licence consents. There are upwards of 840 point source discharges from urban waste water

treatment plants; 776 discharges to waters licensed by Local Authorities (Section 4 licensed discharges) and 186 discharges to waters licensed by the EPA (IPPC licensed discharges).

Data obtained or estimated concerning flows and pollution loading is presented

in Appendix E of Volume 2. 7.3.4 Assimilative Capacity of Receiving Waters The magnitude of the pressure must be compared against the assimilative

capacity of the receiving water. By calculating the dilution available in the receiving water, a determination can be made if a discharge is likely to impact significantly on the receiving water body such as to cause deterioration in status or to prevent the water body from achieving ‘Good Status’.

The assimilative capacity of the receiving water body was determined on the

95%-ile flow. Flow data were sourced from the EPA and where data gaps existed i.e. where there was an absence of hydrometric data available for the receiving water, estimates were used. The estimates were derived from a flow estimating tool developed by the Western River Basin District in collaboration with the EPA. For waters designated as sensitive under the Urban Waste Water Regulations, median flows were applied.

The available dilutions based on the 95%-ile flows were considered in the

following terms:- - Available dilutions <25. - Available dilutions 25 – 100 - Available dilutions >100 The available dilutions based on the median flows were considered in the

following terms:- - Available dilutions <25. - Available dilutions 25 – 100 - Available dilutions 100 – 150 - Available dilutions > 150 The above ranges of dilutions are somewhat arbitrary and intended to provide

an initial view of the possible risk to water quality. Typically, waste water treatment plants with tertiary treatment are designed to achieve a 10/10 effluent (10mg/litre BOD, 10 mg/l SS). Secondary treatment plants are designed to

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achieve a 25/35 effluent (25mg/litre BOD, 35 mg/l SS). At 10 dilutions, a tertiary treated effluent will not raise the BOD in the receiving water body by more than 1 mg/litre. Similarly, with 25 dilutions, a secondary treated effluent will not cause an increase of 1mg/litre.

The calculation of the assimilative capacity requires details of flows and

background concentrations in the receiving waters. Some of the information gathered is based on estimates and/or information from monitoring stations remote from the point of discharge. Therefore the results of the analysis should not be taken as definitive but rather a best estimate. For the purposes of identifying water bodies at risk from point source discharges, a dilution of 25 or less is taken as the threshold for categorising water bodies at risk. Where the water body is designated a nutrient sensitive area or is upstream of a nutrient sensitive area, a dilution of less than 100 (based on median flow data) is taken as the threshold for categorising water bodies at risk.

Existing data sources have been used to establish assimilative capacities. The

monitoring programme which has been established under the WFD and the waste water licence discharge (authorisation) licensing system will provide more precise information on the characteristics of the discharge and the impact on the receiving waters. In addition, hydrometric monitoring stations are being upgraded to provide better and more targeted information. When information becomes available, the assimilative capacity at each discharge can be more accurately predicted.

7.3.5 Capacity at Waste Water Treatment Plants The quality of the discharge from urban waste water treatment plants is

dependent on the level of treatment applied and the design capacity of the waste water treatment plant. If the design capacity is exceeded, the quality of the treated effluent may deteriorate. A review of the design capacity of waste water treatment plants was carried out and compared to the existing and future loading. Where the information suggests that the plant is at design capacity or likely to exceed capacity based on population projections, the receiving water body was deemed to be at risk.

Due to uncertainties as to the validity of the available information and the

accuracy of the estimates, only waste water treatment plants which exceed design capacity by more than 10% of the reported capacity were included in the risk assessment.

7.3.6 Protected Areas The Water Framework Directive has defined Protected Areas as those areas

which have been designated as requiring special protection of their surface waters or ground waters, or for the conservation of habitats and species directly dependant on water. Included in the designation of Protected Areas are:-

- Bodies of water used for the abstraction of water for human consumption,

providing more than 10 m3/day or serving more than 50 persons (and bodies of water for such future use).

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- Areas designated for the protection of economically significant aquatic species.

- Designated recreational waters and bathing waters. - Nutrient sensitive areas. - Areas designated for the protection of habitats or species. Other areas which are considered worthy of Protected Area status but which

have yet to be included as a criteria for designation include habitats for the Fresh Water Pearl Mussel (Margaritifera).

The significance of a point source discharge in the context of the sensitivity of

a Protected Area depends on whether the Protected Area is water dependant and on the water quality parameters which, if impacted, would pose a threat to the sustainability and status of a Protected Area.

Point source discharges which discharge into or upstream of a Protected Area

are considered to have the potential to influence the water quality in the protected area. The distance upstream of a Protected Area beyond which the discharge from the point source is not considered to have a significant impact will be unique to each location. Point source discharges were placed at risk if there was a drinking water abstraction site within 10km downstream. If a point source was discharging within 10km upstream or directly to a salmonid water it was included in the risk assessment. Shellfish and bathing waters sites were included where the point source was discharging directly into the water body or was within 1km of the designated area. Point sources discharging directly to SACs, SPAs and nutrient sensitive areas or within their respective upstream catchments were included in the risk assessment. This criteria is based on the opinions of the authors of this report and not on any scientific study. It will be necessary to better define this limit for each individual area based on the results of the monitoring programme and the assessment of the effectiveness of the measures during the first River Basin Management Plan cycle.

7.3.7 High Status Sites High Status Sites are considered to be bodies of water where the existing Q-

rating is 4-5 or better. The objectives of the WFD are to prevent any deterioration in existing status.

If the existing status in the receiving waters downstream of a point source

discharge is high status, then it could be reasonably inferred that the discharge is not impacting on the water quality status and therefore poses no risk. However, if there has been a deterioration in status from Q5 to Q4/5, albeit that both are defined as high status, the point source may be the cause of the deterioration. Any change in the discharge through increasing pollution loading resulting from increasing population within the catchment of the WWTP or a deterioration in the performance of the WWTP through poor operation and maintenance could cause a further deterioration in status.

For the purposes of the risk assessment High Status Sites are considered to be

at risk from point source pressures if there has been deterioration in

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downstream status within 3km of the discharge. Also, High Status Sites tend to be in the upper catchments, with lower in-steam flows and, therefore, less available dilution. Population increases may result in greater pollution loading. Inadequate dilution in the receiving waters may cause deterioration in status and hence in such circumstances the water body is at risk from the point source discharge.

7.4 Further Characterisation – Updated Risk Assessment

7.4.1 General

The risk assessment is based on criteria which, if relevant, represent a risk to the status of the receiving water body. The criteria take into consideration the particulars relating to the discharge and matters relating to the receiving water as discussed previously in this chapter. The criteria are intended to be evidence based in respect of the point source discharge. In other words, where the available information suggests that the point source discharge is impacting on the receiving water quality or would likely impact under certain future circumstances, the water body is deemed to be at risk.

7.4.2 Criteria used in Risk Assessment

The following general criteria have been tested against each point source discharge. • Deterioration in Q-status between u/s and d/s of a point source discharge. • Q value downstream less than Q4 • Historical deterioration in downstream Q value • WWTP at capacity • Insufficient assimilative capacity in receiving waters • Failure of Bathing water quality standards • Failure of Shellfish water quality standards.

These general criteria have been further redefined to prioritise the risk based on the strength of the evidence that the point source discharge is impacting water quality as follows.

• Deterioration in Q-status between u/s and d/s of a point source discharge

where the d/s monitoring station is within 3 km. • Q value within 3km downstream less than Q4 • Historical deterioration in Q value within 3km d/s (e.g.. Q5 – Q4/Q5) • WWTP at capacity (existing & future) • Insufficient assimilative capacity in receiving waters (existing & future)

7.4.3 Application of the Risk Assessment

The criteria described in 7.4.2 above have been tested for all point source discharges and receiving water bodies. If any of the criteria apply to the point source discharge the receiving water body was deemed to be at risk and designated as such. The following are examples of the application of the risk assessment applied to Protected Areas. A similar assessment was carried out for all other areas.

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Fresh water Pearl Mussel (FPM)

FPM catchments are reported to require high quality water for recruitment

(habitation and propogation). If the water quality status is below the required quality status the environmental objectives of the WFD will not be met. If a point source discharge is located within the Protected Area and evidence suggests that the discharge is having an impact, then the water body is considered to be at risk.

The following are the criteria used in the risk assessment to test if a water body

within a FPM area was at risk from a point source discharge.

Areas Designated for the Protection of Habitats or Species

Areas which are designated as protected areas for habitats or species include

SPA’s, and SAC’s. For those that are dependant on water and in particular water quality, the risk attached to point source discharges may be determined by a deterioration in water quality status from upstream to downstream of the point source or if the existing downstream water quality is less than Good Status. Similarly water bodies in designated protected areas can be at risk from point source discharges if the point source discharge is not complying with Basic Measures.

The following are the criteria used in the risk assessment to test if a water body

within an area designated for the protection of habitats or species was at risk from a point source discharge.

Economically Significant Aquatic Species - Salmonid

The Regulations governing the designation of Salmonid Areas under the

Freshwater Fish Directive require water quality standards which include chemical parameters. Point source discharges in the catchment upstream of the water designated as a Salmonid Protected Area may pose a risk to the salmonid waters. For the purpose of the risk assessment the distance upstream has been taken as 10km. This is an arbitrary value which is deemed to err on the side of caution.

- Historical decline in d/s Q value within 3km of discharge (Q5 to Q4/Q5) - Q value within 3km d/s <Q4 - Deterioration in Q value between u/s and d/s with stations within 3km of

discharge - Insufficient assimilative capacity - WWTP at capacity

- Q value within 3km d/s <Q4 - Deterioration in Q value between u/s and d/s with stations within 3km of

discharge - Insufficient assimilative capacity

- WWTP at capacity

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The following are the criteria used in the risk assessment to test if a water body within an area designated as a salmonid area is at risk from a point source discharge.

Economically Significant Aquatic Species – Shellfish

If point source discharges to these areas do not comply with the Basic

Measures, then the water body is at risk of failing to meet the environmental objectives.

Nutrient Sensitive Areas

Water bodies within nutrient sensitive areas are considered to be at risk from

point source discharges if there is insufficient assimilative capacity in the receiving waters under existing or future conditions to meet with the environmental quality objectives. The risk from point source discharges may result from discharges in the catchment up stream of the water body designated as Sensitive under the Urban Waste Water Treatment Regulations, 2001-2004. For the purposes of the risk assessment the impacts from discharges in any part of the upstream catchment have been assessed.

The following are the criteria used in the risk assessment to test if a water body

within an area designated as a sensitive area is at risk from a point source discharge.

Abstraction of Drinking Water

Article 7 of the WFD requires that safeguard zones are established to protect

against the deterioration of the quality of water bodies used for abstraction of drinking water, with the aim of reducing the level of treatment required at water treatment plants. Water abstraction from surface water generally receives filtration and chlorination at the water treatment plant. Most recently it has been suggested that discharges from WWTP’s may be a contributory

- Q value within 3km d/s <4 - Deterioration in Q value between u/s and d/s with stations within 3km of

discharge - Insufficient assimilative capacity

- WWTP at capacity

- Q value within 3km d/s <Q4 - Deterioration in Q value between u/s and d/s with stations within 3km of

discharge - Insufficient assimilative capacity including nutrients.

- WWTP at capacity

- Monitoring data for receiving waters non-compliant with standards

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factor for the presence of cryptosporidium in raw water entering water treatment plants which necessitates a higher level of treatment.

Water bodies designated as Protected Areas for abstraction of drinking water

are considered to be at risk if there is evidence of deterioration in water quality due to any point source discharge located within the abstraction safeguard zone. These zones have yet to be delineated and therefore for the purposes of the risk assessment point source discharges within 10 km u/s of the surface water abstraction point have been considered vis-à-vis the risk to the protected drinking water abstraction area.

The following are the criteria used in the risk assessment to test if a water body

within an area designated as a Protected Area for drinking water abstraction was at risk from a point source discharge within 10 km upstream of the abstraction point.

Bathing Waters

Designated bathing waters may be placed at risk from point source discharges

if the magnitude of the discharge is such that the receiving water fails to meet water quality standards required for bathing waters. For this reason impact data is used to determine the risk from a point source discharge.

The following are the criteria used in the risk assessment to test if a water body

within an area designated as a bathing water is at risk from a point source discharge.

7.4.4 Summary of Results of Risk Assessment The criteria for the risk to achieving the objectives of the WFD have been

applied to all point source pressures. Nationally 458 point source discharges from urban waste water treatment plants are considered to put the receiving water body at risk of failing to achieve the objectives of the WFD. This includes assessing the points under future conditions up to the year 2015. Likewise 348 IPPC and Section 4 licensed discharges are considered to put the receiving water body at risk. The impacts of point source discharges are causing a total of 602 water bodies (13.5% of all water bodies) to be at risk of failing to achieve the objectives. The locations of the water bodies at risk are shown on the map below.

- Insufficient assimilative capacity.

- Monitoring data for receiving waters non-compliant with standards

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Details concerning the water bodies at risk from discharges from urban waste water treatment plants are given in the table and histogram below. It is important to recognise that more than one of the risk criteria may have applied to a single discharge hence the numbers failing each criteria are greater than the total number of point discharges.

Urban WWTP Discharges - Results Risk Assessment

0

50

100

150

200

250

300

350

400

450

500

No. of

WWTPs

Failing

Tota

l

Q A

ss

Ass C

ap (C

u rrent

)

Ass C

ap (F

u ture

)

Ass C

ap N

ut (C

urre

nt)

Ass C

ap N

u t (Fut

ure)

WW

TP C

ap (C

urre

nt)

WW

TP Cap

(Fut

ure)

Shell fi s

h W

a ter

Bathin

g W

ater

>1 Fa

il ure

Criteria

Revised Risk Assessment - WWTPs Overall

< 500 PE

1000 - 500 PE

2000 - 1000 PE

> 2000 PE

Criteria No. of

WWTPs

% of

WWTPs

No. of Water Bodies

Total Numbers Causing WBs to be At-Risk 458

374 Q Asse ssment 176 38% 157

Assimilative Capacity Assessment (Current) 241 53% 219

Assimilative Capacity Assessment (Future) 247 54% 225

Assimilative Capacity Assessment Nutrients (Current) 95 21% 85

Assimilative Capacity Assessment Nutrients (Future) 101 22% 90

WWTP Capacity Assessment (Current) 109 24% 101

WWTP Capacity Assessment (Future) 200 44% 165

Failure of Shellfish water quality standards 2 <1% 2

Failure of Bathing water quality standards 10 2% 9

Failure of more than one of the above criteria 330 72% 288

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The above data can be further outlined in terms of waste water treatment plant capacity expressed as P.E. as follows: Urban WWTP Discharges - Results Risk Assessment – with P.E. <500

0

20

40

60

80

100

120

140

160

180

No. of

WWTPs

Failing

Total

Q A

ss

Ass Ca p

(Cur

rent)

Ass

Cap

(Future)

Ass

Cap

Nut (

Curre

nt)

Ass C

ap Nut

(Future

)

WW

TP

Cap

(Cur

rent

)

WW

TP C

ap (F

uture

)

Shell fish

Wate r

Bathin g

Wat

er

>1 Fai

lure

Criteria

WWTP Discharges - Results Risk Assessment – with P.E.

<500

Total

Q Ass

Ass Cap (Current)

Ass Cap (Future)

Ass Cap Nut (Current)

Ass Cap Nut (Future)

WWTP Cap (Current)

WWTP Cap (Future)

Shellfish Water

Bathing Water

>1 Failure

Criteria No. of WWTPs

Total Numbers Causing WBs to be At-Risk 167

Q Asse ssment 62

Assimilative Capacity Assessment (Current) 77

Assimilative Capacity Assessment (Future) 80

Assimilative Capacity Assessment Nutrients (Current) 40

Assimilative Capacity Assessment Nutrients (Future) 43

WWTP Capacity Assessment (Current) 22

WWTP Capacity Assessment (Future) 57

Failure of Shellfish water quality standards 0

Failure of Bathing water quality standards 1

Failure of more than one of the above criteria 108

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Urban WWTP Discharges - Results Risk Assessment – with P.E. >500 and <1000

0

10

20

30

40

50

60

70

80

90

100

No. of

WWTPs

Failing

Total

Q A

ss

Ass

Ca p

(Cur

rent)

Ass

Cap

(Fu

ture)

Ass

Cap

Nu t (

Cur

rent

)

Ass

Cap

Nut

(Fut

ure)

WW

TP C

ap

(Cur

rent

)

WW

TP C

ap (F

utur

e)

She

ll fish

Water

Bathing W

ater

>1 Fa

ilure

Criteria

WWTP Discharges - Results Risk Assessment – with P.E.

>500 and <1000

Total

Q Ass

Ass Cap (Current)

Ass Cap (Future)

Ass Cap Nut (Current)

Ass Cap Nut (Future)

WWTP Cap (Current)

WWTP Cap (Future)

Shellfish Water

Bathing Water

>1 Failure

Criteria No. of WWTPs

Total Numbers Causing WBs to be At-Risk 95 Q Asse ssment 32

Assimilative Capacity Assessment (Current) 54

Assimilative Capacity Assessment (Future) 55

Assimilative Capacity Assessment Nutrients (Current) 12

Assimilative Capacity Assessment Nutrients (Future) 13

WWTP Capacity Assessment (Current) 25

WWTP Capacity Assessment (Future) 37

Failure of Shellfish water quality standards 0

Failure of Bathing water quality standards 0

Failure of more than one of the above criteria 69

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Urban WWTP Discharges - Results Risk Assessment – with P.E. >1000 and <2000

0

10

20

30

40

50

60

70

80

No. of

WWTPs

Failing

Total

Q A

ss

Ass

Ca p

(Cur

rent)

Ass

Cap

(Fu

ture)

Ass

Cap

Nu t (

Cur

rent

)

Ass

Cap

Nut

(Fut

ure)

WW

TP C

ap

(Cur

rent

)

WW

TP C

ap (F

utur

e)

She

ll fish

Water

Bathing W

ater

>1 Fa

ilure

Criteria

WWTP Discharges - Results Risk Assessment – with P.E.

>1000 and <2000

Total

Q Ass

Ass Cap (Current)

Ass Cap (Future)

Ass Cap Nut (Current)

Ass Cap Nut (Future)

WWTP Cap (Current)

WWTP Cap (Future)

Shellfish Water

Bathing Water

>1 Failure

Criteria No. of WWTPs

Total Numbers Causing WBs to be At-Risk 75 Q Asse ssment 34

Assimilative Capacity Assessment (Current) 40

Assimilative Capacity Assessment (Future) 42

Assimilative Capacity Assessment Nutrients (Current) 13

Assimilative Capacity Assessment Nutrients (Future) 16

WWTP Capacity Assessment (Current) 22

WWTP Capacity Assessment (Future) 37

Failure of Shellfish water quality standards 1

Failure of Bathing water quality standards 1

Failure of more than one of the above criteria 57

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Urban WWTP Discharges - Results Risk Assessment – with P.E. >2000

0

20

40

60

80

100

120

140

No. of

WWTPs

Failing

Total

Q A

ss

Ass Ca p

(Cur

rent)

Ass

Cap

(Future)

Ass

Cap

Nut (

Curre

nt)

Ass C

ap Nut

(Future

)

WW

TP

Cap

(Cur

rent

)

WW

TP C

ap (F

uture

)

Shell fish

Wate r

Bathin g

Wat

er

>1 Fai

lure

Criteria

WWTP Discharges - Results Risk Assessment – with P.E.

>2000

Total

Q Ass

Ass Cap (Current)

Ass Cap (Future)

Ass Cap Nut (Current)

Ass Cap Nut (Future)

WWTP Cap (Current)

WWTP Cap (Future)

Shellfish Water

Bathing Water

>1 Failure

Criteria No. of WWTPs

Total Numbers Causing WBs to be At-Risk 121 Q Asse ssment 48

Assimilative Capacity Assessment (Current) 70

Assimilative Capacity Assessment (Future) 70

Assimilative Capacity Assessment Nutrients (Current) 30

Assimilative Capacity Assessment Nutrients (Future) 29

WWTP Capacity Assessment (Current) 22

WWTP Capacity Assessment (Future) 69

Failure of Shellfish water quality standards 1

Failure of Bathing water quality standards 8

Failure of more than one of the above criteria 96

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Details concerning the water bodies at risk from discharges from licensed industries (IPC & Section 4 licences) are given in the table and histogram below. Licensed Discharges – Results of Risk Assessment

0

50

100

150

200

250

300

350

No. of Industries

Failing

Total

Q A

ss

Ass C

ap Ass

Bathin

g Ass

Shellfish

Ass

>1 Ass

Criteria

Revised Risk Assessment - Industry

Total

Q Ass

Ass Cap Ass

Bathing Ass

Shel lfish Ass

>1 Ass

Criteria No. of

Industries % Failing each

Criteria No. of Water

Bodies Total Numbers 348 237

Q Asse ssment 144 41% 109

Assimilative Capacity Assessment 228 65% 158

Bathing Water Assessment 9 3% 7

Shellfish Water Assessment 4 1% 3

Failure of more than one of the above criteria 36 10% 29

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8.0 PRIORITISATION OF WATER BODIES AT RISK

8.1 Introduction

Article 2 of the WFD requires that each Member State shall establish a

Programme of Measures to achieve the objectives established under Article 4. It is unlikely that all objectives will be achieved for all water bodies within the

first River Basin District Management Plan cycle. It will therefore be necessary to prioritise the implementation of the measures taking into consideration the requirements of the Directive and the ability of river basin district authorities to effect measures within the period of the first management plan cycle.

Some measures may be technically difficult to achieve or involve

disproportionate costs with modest or negligible benefits. In such circumstances the implementation of such measures may be of lower priority than measures which will deliver more cost effective reductions in risk or improvements in water quality. Also, the risk attached to some water bodies may be time related and as such measures may be less urgent for example, increases in population occurring after the period of the first River Basin District Management Plan.

Some water bodies are at greater risk of failing the objectives due to the

magnitude of the pressure and / or the degree of sensitivity of the body of water. These water bodies may warrant more urgent implementation of the Programme of Measures.

8.2 Background The environmental objectives of the WFD are set out in Article 4. These

objectives require member states to take actions within timelines. For actions relating to surface waters, Member States are required to:-

− implement the necessary measures to prevent deterioration of the status of

all bodies of surface water: − protect, enhance and restore all bodies of surface water with the aim of

achieving good surface water status by 2015: − progressively reduce pollution from priority substances, and to cease or

phase out emissions discharges and losses of priority hazardous substances. − For protected areas the Directive requires that Member States shall achieve

compliance with standards and objectives by 2015 at the latest. The objectives in respect of Protected Area must be achieved by the 2015

deadline. That suggests a greater priority to implement the necessary measures in respect of Protected Areas due to the absolute deadline for achieving compliance with the standards and objectives. Likewise Member States are required to implement measures to prevent deterioration of the status with no reference to a time scale hence such measures should be implemented in the first River Basin District Plan cycle.

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8.3 Prioritising the Implementation of the Programme of Measures

It is evident from the Directive that the achievement of the objectives for

Protected Areas must receive the highest priority since the objectives must be achieved at the latest by December 2015. It can also be inferred that if there is to be an overall improvement in water quality to at least “Good Status” then in the first instance there should be no deterioration in the existing quality status. Priority should also be given in the programme for the implementation of measures to prevent deterioration as required by Article 1(a) (i).

Water bodies are at greatest risk of failing environmental objectives due to

point source discharge where the existing water quality is less than “Good Status” and the evidence suggests that the point source discharge is the primary cause, for example, where there is deterioration in the water quality from upstream to downstream of a point source discharge where the monitoring points are located in close proximity to the point of discharge. The causes of same may be attributable to the lack of assimilative capacity in the receiving waters, lack of capacity at the treatment plant or insufficient level of treatment.

In other cases the risk from point source discharges may be less evident or time

related. For instance there may be deterioration in receiving water quality from upstream to downstream of a point source discharge but the monitoring points may be some distance from the discharge point and there may be other pressures within the catchment which could be responsible for the deterioration. Also the risk may be due to future development pressures within the catchment which may increase the loading to existing treatment facilities. In this instance the programme for the implementation of the measure can be aligned with the programme for development.

8.4 Criteria for prioritisation

The general hierarchy for the prioritisation of the measures in respect of point source discharge is illustrated in Figure 8.1. In all cases the Basic Measures must be implemented (a full definition of Basic Measures in provided in Chapter 10 of this report). For Supplementary Measures or measures which are more stringent than the Basic Measures, disproportionate costs and technical feasibility may dictate that not all of the measures can be implemented within the first RBDMP cycle. In such circumstances prioritisation may be considered.

The Basic Measures must be implemented for all water bodies as part of

the first River Basin District Management Plan Cycle. Priority can be given to Supplementary Measures by setting objectives.

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Figure 8.1 – Prioritisation of Water Bodies ‘At Risk’

The model developed for the risk assessment has been structured to allocate point source discharges, and hence water bodies, to the relative priority category. Relevant criteria have been tested against each discharge to determine if the discharge is putting the water body at risk. The model also identifies which of the specific criteria is causing the risk. Figures 8.2 & 8.3 and show the general approach to determining the priority of water bodies at risk. This is based on the risk criteria described in Section 7 of the report. The results of the prioritisation are summarised below.

Protected Areas &

Existing High

Status Sites

Water Bodies at

Risk U/S of

Protected Area

Highest Priority

High Priority

Water Bodies of

Less than Good

Status or at Risk

of Deterioration

Medium Priority

Other Water

Bodies at Risk

from Existing or Possible Future

Loading

Lower Priority

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Figure 8.2 WWTP Point Source Discharge Priority Chart

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Figure 8.3 industrial Point Source Discharge Priority Chart

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Highest Priority – Protected Areas at Risk In implementing the programme of Supplementary Measures priority should

be given to point source pressures which put at risk the achievement of Good Status in Protected Areas. Protected Areas are listed in Annex IV of the WFD. These include:-

− Areas designated for the abstraction of water for human consumption. − Areas designated for the protection of economically significant aquatic

species. − Recreational and bathing waters. − Nutrient sensitive areas − Areas designated for the protection of habitats and species where the

maintenance or improvement of the status of water is important. In addition to the above, water bodies identified as habitats for the freshwater

pearl mussel (FPM) or water bodies upstream of habitats of FPM are considered potential areas to which special importance is attached.

Water bodies which are designated as Protected Areas and which are

considered to be at risk from point source discharges (existing and future conditions) are considered to demand the highest priority when implementing the Programme of Measures.

The preservation of High Status Sites are also to be considered as highest

priority. High Status Sites are water bodies where the existing water quality is of the highest quality. The identification of the High Status Sites has yet to be finalised and therefore these have not been assessed in the risk assessment. The consideration of these areas may add to the numbers of water bodies in the priority category.

Summary data for the number of water bodies considered to warrant the

highest priority status (Priority 1 & 2) are presented in the following tables and histograms.

There are 187 urban wastewater treatment plants which discharge directly into

a Protected Area and the magnitude of the existing discharge is putting the receiving water body at risk in accordance with the risk assessment criteria described in Section 7. The total number of water bodies impacted is 166 (more than one WWTP may discharge into the same water body).

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Criteria No. of WWTPs No. of Water

Bodies

Total Numbers 187 166 Q Asse ssment 75 68

Assimilative Capacity Assessment 90 84

Assimilative Capacity Assessment (Nutrients) 16 16

WWTP Capacity Assessment 60 55

Bathing Water Assessment 10 9

Shellfish Water Assessment 2 2

Failure of more than one of the above criteria 51 49

Urban WWTPs Causing Protected Areas to be At-Risk – Priority 1

0

20

40

60

80

100

120

140

160

180

200

No. of

WWTP

Fa iling

Total Q

Ass C

ap

Ass C

ap (N

ut)

WW

TP C

apac

ity

Bathin

g W

ater

Shel lf

ish W

ater

> 1 F

ailur e

Criteria

WWTP - Priority 1

Total

Q

Ass Cap

Ass Cap (Nut)

WWTP Capacity

Bathing Water

Shellfish Water

> 1 Failure

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There are 170 urban wastewater treatment plants which discharge directly into a Protected Area and where the increase in the magnitude of the pressure resulting from future population growth is putting the water body at risk in accordance with the risk assessment criteria described in Section 7. The total number of water bodies impacted is 141.

It should be noted that High Status Sites are to be considered as Priority 2.

However, the data set identifying the locations of High Status Sites was not available at the time of this report and therefore the numbers of Priority 2 WWTPs is likely to increase.

Revised Risk Assessment for MIR – Priority 2

0

20

40

60

80

100

120

140

160

180

No. of

WWTPs

Failing

Total

Ass C

ap

Ass C

ap (N

ut)

WW

TP C

apac

ity

> 1 F

ailure

Criteria

WWTP- Priority 2

Total

Ass Cap

Ass Cap (Nut)

WWTP Capacity

> 1 Fai lure

Criteria No. of WWTPS

Total Numbers 170 Assimilative Capacity Assessment 87

Assimilative Capacity Assessment (Nutrients) 16

WWTP Capacity Assessment 112

Failure of more than one of the above criteria 40

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There are 114 point source discharges from licensed activities which discharge directly into a Protected Area and the magnitude of the existing discharge is putting the receiving water body at risk in accordance with the risk assessment criteria described in Section 7. The total number of water bodies impacted is 97. Revised Risk Assessment for MIR – Priority 1 – Industry

0

20

40

60

80

100

120

No. of Industries

Fa iling

Total Q

Ass C

ap

Bathin

g W

ater

Shellfi

s h W

ater

>1 Fai lu

re

Criteria

Industry - Priority 1

Total

Q

Ass Cap

Bathing Water

Shellfish Water

>1 Failure

Criteria No. of Industries

Total Numbers 114 Q Asse ssment 33

Assimilative Capacity Assessment 78

Bathing Water Quality Standards Failure 9

Shellfish Water Quality Standards Failure 4

Failure of more than one of the above criteria 10

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There are 269 point source discharges from licensed activities which discharge to Protected Area catchments and where the existing magnitude of the pressure is putting the water body at risk in accordance with the risk assessment criteria described in Section 7. The total number of water bodies impacted is 189.

Criteria No. of Industries

Total Numbers 269 Q Asse ssment 111

Assimilative Capacity Assessment 183

Failure of more than one of the above criteria 25

Revised Risk Assessment for MIR – Priority 2 - Industry

0

50

100

150

200

250

300

No.of Industrial

Failures

Total N

umbers

Q A

ss

Ass C

ap A

ss

>1 C

ri ter

ia F

ailu

re

Criteria

Industry - Priority 2

Total Numbers

Q Ass

Ass Cap Ass

>1 Criteria Failure

High Priority – Water Bodies at Risk u/s of Protected Areas

Water bodies which discharge to a water body which is designated as a protected area, contribute to the flow in the protected area. If the u/s water body is at risk of failing to achieve water quality objectives then there is a potential for that waterbody to put the downstream Protected Area at risk. For this reason such water bodies are deemed high priority (Priority 3 & 4) in the context of the implementation of the Programme of Measures.

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There are 336 urban wastewater treatment plants which discharge upstream of a Protected Area and the magnitude of the existing discharge is putting the receiving water body at risk in accordance with the risk assessment criteria described in Section 7. The total number of water bodies impacted is 285.

Criteria No. of WWTPS

Total Numbers 336 Q Asse ssment 144

Assimilative Capacity Assessment 207

Assimilative Capacity Assessment (Nutrients) 79

WWTP Capacity Assessment 91

Failure of more than one of the above criteria 142

Revised Risk Assessment for MIR – Priority 3

0

50

100

150

200

250

300

350

No. of

WWTP

Failing

Tota l

Q A

ss

Ass C

ap

Ass C

ap (N

ut)

WW

TP C

apacit

y

> 1 F

ailu re

Criteria

WWTP - Priority 3

Total

Q Ass

Ass Cap

Ass Cap (Nut)

WWTP Capacity

> 1 Failure

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There are 311 urban wastewater treatment plants which discharge upstream of a Protected Area and where the increase in the magnitude of the pressure resulting from future population growth is putting the water body at risk in accordance with the risk assessment criteria described in Section 7.

Criteria No. of WWTPS

Total Numbers 311 Assimilative Capacity Assessment 209

Assimilative Capacity Assessment (Nutrients) 85

WWTP Capacity Assessment 167

Failure of more than one of the above criteria 124

Revised Risk Assessment for MIR – Priority 4

0

50

100

150

200

250

300

350

No. of

WW TP

Failing

Tota

l

Ass

Cap

Ass C

ap (Nut)

WW

TP C

apacity

> 1 F

ailure

Criteria

WWTP- Priority 4

Total

Ass Cap

Ass Cap (Nut)

WWTP Capac ity

> 1 Failure

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Medium Priority – Water Bodies at Less than Good Status or at Risk of Deterioration

The WFD requires Member States to implement measures to prevent

deterioration in the existing water quality status. If a point source is discharging to a water body and there is strong evidence to suggest that the point source is the cause of deterioration in water quality or there is a risk of deterioration, then measures must be implemented to arrest/prevent such deterioration.

If there is a deterioration in water quality from upstream to downstream

monitoring points, even though the downstream water quality is Q4 or better, measures must be implemented to prevent any further deterioration. Similarly, measures must be implemented if the existing downstream water quality is Good Status or better (i.e. Q4 or Q5) but there has been a historical deterioration in status (i.e. Q 5 to Q4) resulting from a point source.

Where the existing water quality d/s of the point of discharge is less than Good

Status and there is strong evidence to suggest that the point source is the cause of this, measures will have to be implemented to restore the water quality to Good Status. The numbers where this criteria applies are given in the National statistics shown in the table and histogram in Section 7.4.4.

Lower Priority – Other At Risk Water Bodies The criteria for the risk assessment rely on impact data and estimates of flow

and pollution loading. Water bodies have been designated at risk even though there is no direct evidence of an impact from the point source on water quality status. The water quality may be at Good Status and there may be no evidence of a deterioration in quality immediately between u/s and d/s of the point of discharge. However, the available information may have indicated the there is a lack of assimilative capacity in the receiving waters or the waste water treatment plant is at its design capacity. Likewise future estimates on plant loading may exceed plant capacity or reduce the assimilative capacity.

In the above circumstances the impact from point sources is less certain even

though a risk to water quality has been identified. Measures should be implemented to reduce the risk but such measures are considered less urgent than those described above in the Highest, High and Medium Priority categories.

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9.0 DEVELOPMENT OF SIMCAT MODEL FOR SWRBD

9.1 Introduction

Predictive modelling tools can provide a useful means of determining the impacts on the receiving waters resulting from point source discharges of polluting matter. However, some modelling tools are complex and require a degree of expertise to run the model and to interpret the results. In addition some models require a voluminous amount of input data which may require extensive field surveys.

The WFD Common Implementation Strategy (CIS) Guidance document No. 3.

identifies ‘SIMCAT’ as an example tool to combine pressures with impact assessment at river water body level. The document indicates that once the model is calibrated it can be used by less experienced staff and the outputs are simple and clear.

SIMCAT was developed for the Environmental Agency UK and is widely used

in water quality planning. The model is used by regulatory authorities to determine the impact of point source discharges in carrying out their licensing functions. SIMCAT is currently employed by the Environment Agency (EA) in England and Wales and a number of Regional Councils in the UK. The EA are using SIMCAT as a national management tool to meet with the requirements of the Water Framework Directive. A set of SIMCAT river models covering all of England and Wales has recently been completed.

The tool is primarily intended to investigate the impacts of point source

pollution on the general chemical quality of rivers. It enables the impact of the pressure from each source to be assessed individually and in combination. The diffuse loading can also be derived.

The Water Research Centre (WRc) was employed as an expert Sub-Consultant

to assist the SWRBD in the assessment and development of the SIMCAT model. A full version of the SIMCAT report is available as Appendix D of Volume 2.

9.2 Objectives The SWRBD was tasked with investigating the benefits of SIMCAT as a

management tool to assist River Basin District Authorities in the implementation of the requirements of the WFD.

It was recognised that the approach to monitoring discharges from waste water

treatment plants and to monitoring flows and water quality in the receiving waters in the UK is different to the procedures in Ireland. The data collected in the UK is sufficient to develop a useful SIMCAT model. The first objective of the study was to determine the data requirements necessary to develop a useful SIMCAT model and to determine if that level of data was available in Ireland. If sufficient data was available a pilot model would be developed and tested with the objective of demonstrating the output from SIMCAT and its usefulness in the context of a water quality management tool.

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9.3 Establishment of the Model – Stages of Development

In order to achieve the objectives of the SIMCAT study a number of stages had to be undertaken in development of the model. (Ref Figure 9.1) These included: • Initial Planning and determination of model boundary

• Collation of all the relevant input data from the SWRBD;

• Screen and assess the accuracy of this data;

• Undertake data analysis for producing the SIMCAT model;

• Build a SIMCAT model for the river networks in the SWRBD;

• Calibrate the SIMCAT models for flow and quality to agreed criteria;

• Carry out demonstration modelling scenarios using the calibrated model;

• Produce a report on the outcome of the study together with conclusions and recommendations on its benefits as a river management planning tool.

Reports & Final Model

Flow & Quality Calibration

Model Structure

Calibrated

Model

Model Input Data

Model Boundary

Model Development

Data Analysis

Scenarios & Handover

Initial Planning

Figure 9.1 SWRBD SIMCAT Stages of Model Development

9.3.1 Initial Planning and Determination of Model Boundary

Originally the Blackwater Hydrometric Area 18 was selected as the model

extents and pilot study area. However as the WRc and Environmental Agency (EA) UK were undertaking a lot of SIMCAT work at River Basin District Level in the UK it was agreed to extend the model boundary to cover the entire

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SWRBD. At this scale the extent of work required to roll out the model to the other river basin districts could be determined quite easily.

9.3.2 Model Input Data An assessment was made of the input data requirements to undertake the

SIMCAT pilot study. The data that was required consisted of all available background mapping, pressure and impact data for the SWRBD including:

• Background Ordinance Survey Ireland (OSI) raster and vector mapping,

administrative boundaries, hydrometric areas, river basins, all river reaches, river water bodies, lake water bodies, transitional and coastal water bodies including freshwater limits in the SWRBD.

• River flow data, flow guage locations available river flow data, • Wastewater treatment plant discharge locations and available monitoring

and flow data. • Industrial discharge locations including IP(P)C discharges to surface

waters and Section 4 licence discharge locations. Available consent flow and monitoring data for industrial discharges.

• Abstraction locations and quantity data • Receiving water quality sampling point locations and data, both physio-

chemical and biological • Future discharge location points

A greater amount of time than anticipated was spent on the data collation phase

of the project due to issues such as data gaps and inconsistencies in collection and collation of data The following issues were identified in the datasets and these need to be addressed going forward; • A total of 66 hydrometric flow gauges were identified within the

SWRBD SIMCAT model limits. This is a relatively high density of gauges per length of river. However long term summary statistical data such as daily mean flows was only available from approximately 45 of those. While data was readily available from the Office of Public Works (OPW) hydrometric stations through the OPW website, data had to be obtained from the EPA controlled stations on request. Because of the EPA’s current workload this proved to be extremely time consuming and caused slippage in the overall programme.

• Data gaps were evident in municipal wastewater treatment plant flow

and monitoring data. These data gaps are comprehensively dealt with in chapter 4 of this report and the recommendations should be adopted going forward to address these data gaps.

• Licence consent data was used to address the monitoring data gap

evident in industrial discharges (Local Authority Section 4 data and EPA IP(P)C discharges to surface water) This data gap is being reviewed at present by the Dangerous Substances POMs study and recommendations will be made going forward to address this issue.

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• River water quality data was inconsistent in terms of standards depending on the source of the data e.g. the various forms of phosphorous that were provided as impact data. The inconsistencies were noted and addressed for the purposes of the study. These inconsistencies will be partially addressed under the Water Framework Directive (WFD) monitoring programme but will also need to be addressed in other monitoring programmes complying with various Directives and legislation.

9.3.3 Data Screening and Analysis

SIMCAT requires data for flow and quality to be input as statistical distributions defined using the mean and standard deviation or a percentile value. To ensure the most appropriate statistics are used to represent the river water quality, river flow, effluent quality and effluent flow, software tools and techniques collectively called PSI (Pre SIMCAT investigation) were used. The PSI procedure is a series of steps that converts raw data collected over a number of years into input for a SIMCAT model. These include: • MOT (Multiple Outlier Test) to detect outliers in the datasets. Once the

outliers are detected after further investigation the ‘true’ outliers are removed.

• The SAD (Steps Automatically Detected) programme identifies any sudden

step change in a particular determinand. This may be due to an improvement or degradation in the performance of a waste water treatment or industrial discharge.

• The TOAD (Testing of Assorted Distributions) is run as a final stage in

PSI. This enables the calculation of summary statistics for each determinand for the entire monitoring period.

• Correlation analysis between river and effluent flows, and quality

determinands throughout the catchment is carried out on screened data using the Concentration Flow Correlation (CFC) programme. The objective of this is to show the strength of association between all of the determinands in a dataset and flow.

9.3.4 Model Development

The SWRBD River Water Bodies GIS layer contains the 885 river water bodies used for Article 5 Characterisation. The river segments were merged to give single reaches, headwater-to-confluence, confluence-to-confluence etc. Headwater, confluence, bifurcation and discharge points on the river network were identified and a node inserted at these points. After checking that the river connectivity was correct, Virtual Reaches were added to link the freshwater limits of the independent river basins to create a single model outlet, as required by SIMCAT. Virtual Reaches were also added to represent lakes. The presence of lakes resulted in a break in the river network. In these instances, a Virtual Reach was added to represent the lake and to join the river at the discharge point into the lake and the headwater point where the lake flowed into the river. In cases where more than one river discharged into a lake, the

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discharges were linked together along the perimeter of the lake. The Model Reach structure is illustrated in Figure 9.2

Figure 9.2 SWRBD SIMCAT Model Reach Structure

Each feature-set in turn (abstractions, discharges, flow gauging stations and river quality sites) was imported from the SWRBD feature datasets into the SWRBD SIMCAT model. The distance to the nearest point on the model network was calculated and the feature was ‘snapped’ to this point if the distance was within 500m tolerance. Figure 9.3 Illustrates the SWRBD model features.

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Figure 9.3 SWRBD SIMCAT Model Features

9.3.5 Flow and Quality Calibration

For catchments where there were flow gauge observations available, diffuse

flows were calculated for individual water bodies and applied to reaches within those water bodies as a per kilometre diffuse flow. For each water body the mean and 95%ile low flow values (total and per km2) were estimated by trying to match the downstream flow gauge observations. Each water body was assigned a downstream river flow gauge (Figure 9.4) and flows distributed evenly (per km) across water bodies within the flow gauge catchment to generate the individual water body flows. The mean and 95%ile flows were then calculated on a reach by reach basis using the following equation:

Diffuse Flow (per km) = Total Water Body Flow – the sum of all Headwater

flows within the Water Body / Total reach length within Water Body.

For water body catchments where no downstream flow gauge observations were available (shaded in white in Figure 9.4), the diffuse flows were estimated by taking the flows calculated for similar sized and characterised water bodies where flow information was available and assigning it to these water bodies. The Western River Basin District (WRBD) in conjunction with the EPA have completed a new National Flow Estimation Methodology for unguaged catchments. This methodology was unavailable during the timeframe of this study but could be applied going forward.

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Figure 9.4 SWRBD Flow Calibration – Flow Gauges Used to

Estimate Water Body Diffuse Flows Overall a good manual calibration has been achieved to all of the flow gauges

calibrated in the catchment. The SIMCAT mean flow results for all flow gauges are very close to the observed flow data and most of the flow gauges lie well within the ± 1 standard deviation calibration criteria for mean and 95%ile values.

The manual quality calibration involves adjusting headwater and diffuse flow quality and decay rates to match the observed water quality. The diffuse inputs are added to account for the missing inputs from unmodelled watercourses, effluent discharges and actual diffuse inputs to the river network. For quality parameters, the calibrated 95%iles and means should be within one standard deviation of the observed data 95%iles and means. These criteria apply unless a larger error can be clearly demonstrated to be associated with a model simplification and/or a high variability in observed data. The manual calibration was achieved by applying appropriate water quality diffuse inputs and decay rates estimated from historical data. The main steps in the quality calibration was to assign headwater quality and diffuse quality to all reaches such that the model predicted water quality agrees with the quality statistics provided at river quality monitoring sites.

Overall there was a good match between the predicted and observed mean

quality within the SWRBD. The 95%ile values are less well represented within the model.

Following the manual calibration, a process of automatic addition and removal

of ‘diffuse’ load to river reaches was done to match observed river quality data.

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This auto-calibration process added/removed load per km of river reach length, and the results of this were then carried forward for the scenarios. Some sites that appear inconsistent with other data, were not auto-calibrated; e.g. WQ18B021800 as shown in figure 9.5

Figure 9.5 Auto Calibration in the River Backwater

9.3.6 Scenarios

Assessment was made of three ‘What-if’ scenarios conducted using the auto-

calibrated SWRBD model. The three scenarios investigated were:

� Assess current water quality against WQ standards.

� Modify WWTPs inputs for future growth in PE –assess impact on future water quality.

� Assess impact of climate change reduced flows with future PE growth

(River Bandon only) In order to allow assessment of the results of the scenarios, receiving water

quality standards based on existing legislation, such as the Salmonid Regulations, the proposed environmental quality standards were used. These standards can be revised when the Surface Water Classification Regulations are adopted. The following parameters were looked at:

• B.O.D. • Ammonia • D.O. • PO4-P

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The results show that, for the SWRBD under current quality conditions, a number of water quality sites fail for the various determinands as follows:

• B.O.D.: 25 sites or 5.9% failure rate • Ammonium: 85 sites or 30.4% failure rate • D.O.: 1 site or 0.2% failure rate • PO4-P: 176 sites or 36% failure rate

When applying the future planned conditions after allowing for future growth

there is a small increase in the number of site failures for all parameters except D.O.

Loading pie charts and statistics have been produced for the key inputs to the

waterbodies within the SWRBD, using the results from the current actual scenario. Table 9.1 and Figure 9.6 show the summary statistics for four of the key determinands. What is very striking in the SWRBD is the relatively small contribution that the point source discharges are making to the total loadings. This does not change significantly in the planned future scenario.

Table 9.1 Load Input Summary Statistics – Current Actual Scenario

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Figure 9.6 Loading to the SWRBD Waterbodies for the Current Actual Scenario

In the third scenario a climate change assessment was made for the Future Planned WWTPs in the River Bandon Catchment. To do this, average monthly changes in expected stream flow were applied to the observed flow data for the river Bandon. Table 9.2 shows a summary of the results from the three scenarios on the River Bandon. There is an increase in one site failure for ammonia from the ‘current actual’ to the ‘planned future’ to the ‘climate change’ scenario. All the other determinands remain the same.

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Table 9.2 Summary or Results from Three Scenarios River Bandon 9.4 Development of Model Applications

The above table represents just 3 examples of the numerous scenarios that can be run when the SIMCAT is fully established within a catchment.

Recently, the EA in the UK has developed a national suite of GIS based SIMCAT models for all 11 River Basin Districts in England and Wales. These models are being used by the EA for strategic planning and to support the development of their WFD River Basin Management Plans. As part of this study the National SIMCAT model for the Ribble-Mersey River Basin District was used to create a SIMCAT model of the Ribble Catchment for a Pilot Study (Figure 9.7).

Figure 9.7 River Ribble Catchment

Similar to the SWRBD, the SIMCAT model was used to apportion sources of

pollution across the catchment with respect to a number of parameters including BOD Ammonia and PO4-P. The model was calibrated using diffuse inputs from other models. Figure 9.8 shows the apportionment of load sources for phosphate, BOD and ammonia in the Ribble Catchment following model calibration.

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Ammonia Input to Ribble Catchment

Eff luent

Discharge

67%Urban

Dif fuse

9%

Agricultural

Diff use

24%

Total Input:

1188 kg/d

PO4-P Input to Ribble Catchment

Agricultural

Diff use

9%

Urban

Dif f use

3%

Ef f luent

Discharge

88%

Total Input:

1505 kg/d

BOD Input to Ribble Catchment

Agricultural

Dif fuse

54%

Urban

Dif fuse

17%

Eff luent

Discharge

29%

Total Input:

10414 kg/d

Figure 9.8 Load Apportionment in River Ribble Catchment A number of load reduction scenarios were run with the model to identify the outcome in terms of achieving compliance with the proposed WFD river quality standards. Loads were reduced by tightening the point source consent standards and/or applying a percentage reduction in the agricultural diffuse or urban diffuse loadings. The study recognised that achieving proposed river quality standards for Phosphate was potentially the greatest technical and financial challenge to meet the requirement of the WFD in the UK. For BOD and Ammonia compliance could just about be achieved.

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The Ribble Pilot study has demonstrated that a catchment modelling approach can be used to apportion sources of pollution load across a catchment and to identify the water quality co-benefits of point source and diffuse pollution control measures to achieve compliance with WFD river quality standards.

The issues facing the Ribble catchment are not atypical of other large catchments and River Basin Districts. The results from the study have helped to inform debate over the cost effectiveness of measures and have demonstrated the scale of some of the technical and economic challenges associated with the development and delivery of WFD River Basin Plans.

9.5 Conclusions The SIMCAT pilot study in the SWRBD has shown that the available data is

sufficient to develop and fully calibrate a SIMCAT model for the SWRBD. This would also be the case for the other River Basin Districts in Ireland.

A number of data issues need to be addressed going forward to improve the

efficiency in development, calibration and accuracy of the model, as outlined in section 9.3.2.

The study has demonstrated that SIMCAT modelling can be used to support

RBD catchment planning. Any amount of scenarios can be run from the model. Three example scenarios were shown here for illustrative purposes. The scenarios can be run on a catchment basis to examine the accumulative effects or at an individual point source basis.

The SIMCAT modelling tool can be used to determine load apportionment

within a catchment as both diffuse and point source loads can be calculated based on the receiving water loads.

Specific uses could be the determination of consents at individual point sources

or from a planning perspective determining the location of new point source discharges. In addition it could help to identify the most cost effective point source and diffuse pollution measures across the catchment to achieve compliance with the WFD water quality standards.

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10.0 PROPOSED PROGRAMME OF MEASURES

10.1 Background

10.1.1 The environmental objectives of the Water Framework Directive are set out in

Article 4. Additionally, Article 11 of the Directive requires that each member state shall ensure the establishment of a Programme of Measures in order to achieve the objectives established under Article 4. In establishing the Programme of Measures, account must be taken of the results of the analyses required under Article 5.

10.1.2 Article 5 refers to the characterisation of the River Basin District and the

identification of water bodies at risk of failing to meet the environmental objectives set out in the Water Framework Directive. The characterisation report required under Article 5 was completed in December 2004. Annex II of the Directive requires that further characterisation shall be carried out to optimise the design of the monitoring programme and the Programme of Measures.

10.1.3 The further characterisation of the water bodies in the SWRBD is presented in

the earlier chapters of this report. The results show that 13.5% of water bodies are “at risk” of failing to achieve the environmental objectives set out in Article 4, due to point source discharges. A Programme of Measures must be implemented for those water bodies in accordance with Article 11.

10.2 Definition of Measures

10.2.1 The Water Framework Directive provides two categories of measures:- - Basic Measures - Supplementary Measures 10.2.2 ‘Basic’ Measures are those measures required to implement community

legislation for the protection of water. Basic Measures are listed in Part A of Annex VI and those most relevant to point source discharges include:-

- The Urban Waste Water Treatment Directive (91/271/EEC) - The Integrated Pollution Prevention Control Directive (96/61/EC) - The Bathing Water Directives (76/160/EEC and 2006/7/EC) - The Drinking Water Directive (80/778/EEC), (98/83/EC) - The Environmental Impact Assessment Directive (86/278/EEC) - The Shellfish Waters Directive (79/923/EEC) Paragraph (3) of Article 11 provides a comprehensive description of the

measures which fall within the definition of “Basic” Measures. Additional Basic Measures are listed in Annex IX, which includes:- - The Dangerous Substances Discharges Directive (86/280/EEC). All of the aforementioned Directives have been brought in to force in Irish Law

by various Acts and Regulations. Basic Measures are mandatory and are to be considered as the minimum requirements.

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10.2.3 Article 11 describes ‘Supplementary’ Measures as those measures designed

and implemented in addition to the Basic Measures. A non-exclusive list of such measures is provided in Part B of Annex VI of the Water Framework Directive, some of which include:-

- Legislative Instruments - Administrative Instruments - Emission Controls - Codes of Good Practice - Educational Projects - Research, Development and Demonstration Projects Member states may adopt “further Supplementary Measures” in order to

provide for additional protection or improvement of the waters covered by the Directive and ‘additional measures’ where monitoring or other data indicate that the objectives set out under Article 4 for a water body are unlikely to be met.

10.2.4 Article 11 (2) states that “each Programme of Measures shall include the

‘Basic’ Measures specified in paragraph 3 and, where necessary, ‘supplementary’ measures”.

10.3 Proposed Measures for Water Bodies at Risk from Point Source Discharges

10.3.1 The risk assessment described in Chapter 7 of this report was based on factors

which were considered to be indicative of the risk posed by point source discharges to the status of the receiving waters. These include:-

- Lack of capacity at a waste water treatment plant. - Lack of assimilative capacity in the receiving waters. - Monitoring data suggesting impacts from point source discharges. Measures must be implemented for water bodies determined to be at risk.

Therefore, the measures described hereunder are intended to eliminate or mitigate the impact from point source discharges.

10.3.2 Measures are described as either ‘Basic’ Measures or ‘Supplementary’

Measures. In many cases, actions have been identified which can be implemented under the Basic Measures, such as, conditions in licences issued under the Basic Measures. In other cases, the actions are considered new Supplementary Measures. A summary of the proposed measures is presented in Section 10.4. Measures have been assigned against each of the criteria used in the Risk Assessment.

10.3.3 Waste Water Treatment Plant at Capacity 10.3.3.1 Pressure: Information was gathered as part of the MIR Study concerning the reported

capacity at urban waste water treatment plants. The capacity was compared against the population within the catchment and the projected future population. In this case ‘capacity’ refers to the design BOD loading expressed

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in population equivalent (p.e.) whereby one p.e. represents 60g of BOD per day. The receiving water body was considered to be at risk if sufficient capacity was not available to cater for the existing and/or future loading conditions.

It is evident from the research that, in some cases, Water Services Authorities

are unsure of the capacity of wastewater treatment plants in their functional area, nor have they the facilities in place to measure influent loads and effluent loads (refer to Chapter 4). The existing Regulations (S.I. 254 of 2001) concerning the urban wastewater treatment require Water Services Authorities to monitor discharges, but there is no requirement to monitor influent loads. The loading to the plant versus plant capacity may not be recognised until it is too late, i.e. effluent quality deteriorates. Furthermore, there is no requirement to keep a register of plant capacity. This information is normally recorded in Preliminary Reports which are obtained usually from the Design Consultants. It is anticipated however that the new wastewater treatment plant licenses will record the capacity of plants and this should reduce/eliminate data gaps or inaccuracies in plant capacity data.

If a wastewater treatment plant has insufficient capacity, the cause may be due

to unauthorised discharges from non-domestic activities (licensed or unlicensed). Greater vigilance is required by Water Services Authorities with regards to unauthorised discharges to sewer and to regular monitoring and inspection of licensed discharges.

10.3.3.2 Suggested Solutions/Actions: - Increase in capacity at WWTP in advance of increasing load. - Monitor influent loads at urban waste water treatment plants. - Keep register of plant capacity and update annually and whenever

modifications are made. - Reduce loading to the treatment plants consistent with the design capacity. - Limit or cease the direct importation of materials (e.g. liquid waste,

sludge, leachate to the treatment plant. - Put a procedure in place to monitor compliance of licensed discharges with

the emission limits and conditions set out in the licence and to investigate unauthorised discharges. This needs to be an auditable procedure.

10.3.3.3 Basic Measures: 1) Urban Waste Water Treatment Regulations (SI No. 254 of 2001)

The existing Regulations to implement the Urban Waste Water Treatment

Directive require Water Services Authorities to provide for the collection and treatment of all discharges of waste water. The level of treatment to be provided depends on the size of the agglomeration. The Regulations require that treatment plants are designed, constructed, operated and maintained to ensure sufficient performance. If a plant does not have sufficient capacity to accommodate the influent loading, it is not in compliance with the Regulations. The full implementation of the Regulations and, hence, the existing Basic Measure (Urban Waste Water Treatment Directive) is sufficient to address treatment plant capacity. The

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procedures to ensure continuous implementation need to be better managed and audited.

The Regulations also require Water Services Authorities to take steps, as

may be appropriate under the Local Government (Water Pollution) Act 1977 and under the Environmental Protection Agency Act, 1992 to ensure that the requirements of the Fourth Schedule are met with respect to the discharge of industrial waste water and shall review, and if necessary revise any licence concerned at regular intervals. The Fourth Schedule requires that industrial waste water entering collection systems and urban waste water treatment plants shall be subject to such pre-treatment as is required in order to “ensure that discharges from treatment plants do not adversely effect the environment or prevent receiving waters from complying with other Community Directives”.

If a treatment plant is at or near capacity, the Water Services Authority

should review all licences issued under Section 16 of the Water Pollution Act and IPPC licenses which allow for a discharge to sewer and revise where necessary or appropriate any Section 16 licence which may result in a reduction in the pollution loading entering the collection system. In the case of an IPPC licence, the Water Services Authority should advise the EPA of any recommended revisions.

The Regulations require Water Services Authorities to review at regular

intervals, the licenses issued under Sections 16 of the Local Government Water Pollution Act, 1977, as amended, which pertains to licensing of discharges to sewers. If this provision, which is a Basic Measure, is implemented at regular intervals then the contribution from licensed discharges can be determined and regulated as required.

Water Services Authorities should investigate connections to the collection

system to ensure that licences are in-place for all non domestic discharges which are required to have a licence. The conditions attached to such licences should take cognisance of the capacity at the waste water treatment plant and the ability of the licensee to provide pre-treatment.

2) Waste Water Discharge Authorisation Regulations (IS Nr 684 of 2007)

issued to Implement Requirements of the Dangerous Substances

Directive

Under the Waste Water Discharge Authorisation Regulations, Water

Services Authorities are required to obtain a licence for all discharges resulting from waste water treatment plants and collection networks with a population equivalent of 500 or greater, and a certificate for those less than 500 p.e. The Regulations give powers to the EPA to attach to any licence such conditions as are necessary, in the opinion of the Agency, to give effect to the requirements of existing environmental legislation in the field of water policy. Conditions may be attached to licenses to ensure monitoring of the influent loading and to ensure a register of plant capacity is kept.

The Waste Water Discharge Authorisation Regulations, 2007 require that

Planning Authorities and An Bord Pleanála, when reviewing applications

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for development, shall consider developments which involve discharges to waste water treatment works with regard to emission limit values established for achieving environmental objectives. The Planning Authorities or An Bord Pleanála shall refuse permission or approval for the development; impose conditions; or decide not to proceed with the development where it would lead to the discharge resulting in a non-compliance with emission limit values. Restriction on development under the Regulations will alleviate the pressure on wastewater treatment plants which have insufficient capacity to cater for such developments.

10.3.3.4 Supplementary Measures: Reductions in loadings to the waste water treatment plant are preferable to

expansions to treatment. Whilst it may not be possible to avoid plant expansion the scale of such expansions may be curtailed by reducing the pollution loading entering the collection system or diverting imported materials to another location. The following are suggested Supplementary Measures:-

− Investigate the extent of use and impact of under-sink food waste

disintegrators (FWDs) and introduce controls where appropriate.

− Investigate fats/oils/grease (FOG) concentration in the influent and require FOG control systems e.g. grease traps for activities which result in FOG entering the collection system (bye-laws, licence conditions).

− Initiate a public awareness campaign aimed at reducing pollution loading

entering the collection system.

− Investigate the need to introduce further controls on phosphorous in detergents additional to the voluntary code employed by the Irish Detergent and Allied Products Association, including the possibility of mandatory/statutory limits.

10.3.3.5 Conclusion

The existing Basic Measures, if fully implemented, are adequate to address the risk to receiving water quality from waste water treatment plants with insufficient capacity. Deficiencies have been identified in the implementation of the Basic Measures and suggested actions have been proposed. These are summarised in section 10.4. Supplementary Measures have been proposed to reduce the loading to wastewater treatment plants; these proposed measures could be considered where appropriate.

10.3.4 Insufficient Assimilative Capacity in the Receiving Waters

10.3.4.1 Pressure: The concentrations of some of the parameters of point source discharges are

typically higher than the Environmental Quality Standards (EQSs) set in the receiving waters. The assimilative capacity of a water body is the quantity of substance which may be discharged to it without increasing the concentration of that substance in the water body to a level which would cause deterioration in status of the water body. The quantity of flow and background

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concentrations in the receiving waters are factors in determining the assimilative capacity. However, due to the lack of information on background concentrations, available dilutions is used in the risk assessment to represent assimilative capacity (refer to Chapter 7).

If the receiving water body does not have sufficient dilution in accordance with

the criteria set out in Chapter 7, the water body is considered to be at risk. Chapter 9 investigates the feasibility of using a mathematical modelling

decision support tool such as SIMCAT to access assimilative capacity and pollution load distribution within a catchment. If this tool was universally applied and the data gaps addressed as outlined in chapter 9, it would provide a more systematic approach in assessing the assimilative capacity in receiving waters.

10.3.4.2 Suggested Solutions/Actions: - Assimilative capacity assessment by application of a decision support tool

such as SIMCAT - Relocate the point of discharge. - Apply a higher standard of treatment. - Reduce the loading to the treatment plant. - Require pre-treatment of licensed discharges. 10.3.4.3 Basic Measures: 1. The Urban Waste Water Treatment Regulations (SI No. 254 of 2001) The existing Regulations (SI 254 of 2001) implementing the Urban Waste

Water Treatment Directive specify the concentrations of parameters to be achieved in the treated waste water. The level of treatment applied in accordance with the Regulations may not be sufficient to achieve water quality objectives where sufficient assimilative capacity is not available in the receiving waters.

A reduction in the loading to the waste water treatment plant may reduce

the discharge to conform to the available assimilative capacity in the receiving waters. The review and revision of licence discharges to sewer may achieve this objective. (See paragraph 10.3.3.3 above).

The Water Services Authority should also review licenses for discharges to

waters issued under Section 4 of the Water Pollution Act. If sufficient assimilative capacity is not available in the receiving waters, licence conditions should be amended to require appropriate treatment prior to discharge.

The Regulations require that sanitary authorities carry out, cause to be

carried out or arrange for monitoring of waters subject to a discharge from an urban waste water treatment plant where it can be expected that the receiving waters will be significantly affected. If there is evidence that there is insufficient assimilative capacity in the receiving waters, then it can be expected that the waters will be significantly affected. Monitoring of receiving water is not being routinely carried out by Water Services

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Authorities in these circumstances. This needs to be addressed to ensure full compliance of the Basic Measures. Monitoring may confirm or otherwise the estimates of assimilative capacity and may indicate the level of treatment necessary to achieve water quality objectives.

2. Waste Water Discharge (Authorisation) Regulations (S.I. No. 684 of 2007) The Waste Water Discharge (Authorisation) Regulations require the EPA

to attach to any licence, conditions specifying emission limits and, where appropriate, controls that must not be exceeded in the case of pollutants discharged. If a higher standard of treatment is required at a waste water treatment plant, this can be conditioned in a licence issued by the EPA under the existing Regulations.

3. The Integrated Pollution Prevention Control Directive (96/01/EC)

The existing legislation requires the EPA to licence certain activities as

listed in the Environmental Protection Agency Act, 1992 (as amended). These activities do not therefore fall subject to licensing under Sections 4 and 16 of the Water Pollution Act, 1977. Licenses should be reviewed and appropriate revisions made to the licence conditions where there is insufficient assimilative capacity in the receiving waters.

10.3.4.4 Supplementary Measures:

1 The Water Services Authority may investigate the possibility of relocating the point of discharge to a location where sufficient assimilative capacity is available to absorb the pollution loading from the point source discharge. Relocation of the point of discharge may be impracticable and cost prohibitive. However, there may be circumstances where this represents the most cost effective solution and therefore may be worthy of consideration.

2 The Supplementary Measures described in paragraph 10.3.3.4 above

regarding reductions in loadings to the wastewater treatment plants are also relevant to this circumstance .i.e.

− Investigate the extent of use and impact of under-sink food waste

disintegrators (FWDs) and introduce controls where appropriate.

− Investigate fats/oils/grease (FOG) concentration in the influent and require FOG control systems e.g. grease traps for activities which result in FOG entering the collection system (bye-laws, licence conditions).

− Initiate a public awareness campaign aimed at reducing pollution

loading entering the collection system.

− Investigate the need to introduce further controls on phosphorous in detergents additional to the voluntary code employed by the Irish Detergent and Allied Products Association, including the possibility of mandatory/statutory limits.

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3 Assess the assimilative capacity of receiving waters using a systematic approach such as the application of a decision support tool like SIMCAT

10.3.4.5 Conclusion The assimilative capacity in the receiving waters needs to be considered in the

authorisation of discharges to waters. The existing Basic Measures, if fully implemented, will ensure that emission limit values are consistent with the assimilative capacity in the receiving waters. Supplementary Measures are proposed which could be considered in the circumstances where tighter emission limit values cannot be achieved technically or cost effectively.

10.3.5 Impacts Evident from Monitoring Data (Rivers & Lakes)

10.3.5.1 Pressure: Information on monitoring data has been used in the risk assessment to assess

the impacts of point source discharges. A water body was considered to be at risk if the evidence suggests that point source discharges are contributing to less than Good Status or deterioration of status. The measures described hereunder are for circumstances where it would appear that there is sufficient capacity at the waste water treatment plant and sufficient dilution available in the receiving waters. Other causes for this deterioration, e.g. poor plant operation and maintenance, need to be investigated and actions taken to remedy these.

Treated waste water discharges have yet to be fully characterised with regard to

all parameters which may impact on water quality status. There may be substances present in the waste water at concentrations that impact on status. This may be related to the importation of substances at the treatment plant (sludges, leachate), or contributions to the collection system from licensed discharges, i.e. (shock loads, dangerous substances), or unlicensed/illegal discharges from non-domestic sources.

Poor operation and maintenance procedures at a wastewater treatment plant

may be the cause of impacts in the receiving water. A poorly operated and maintained plant may lead to non-compliance with emission limit values.

10.3.5.2 Suggested Solutions/Actions:

− Provide a higher standard of treatment to remove or reduce specific substances in the treated waste water.

− Initiate investigation into the characteristics of treated waste water, in

addition to the monitoring requirements under the Urban Waste Water Treatment Regulations e.g. BOD, suspended solids etc.

− Investigate contributions from the collection system from licensed and

unlicensed discharges and revise licenses on a regular basis. − Remove or pre-treat for specific substances upstream of their discharge to

the network.

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− Optimise operation and performance of existing wastewater treatment

plants. 10.3.5.3 Basic Measures: 1. Urban Waste Water Treatment Regulations (SI 254 of 2001) The existing Regulations refer only to the treatment and monitoring of

waste water with reference to the parameters listed in the Second Schedule of the Regulations, i.e., BOD, COD, suspended solids, nitrogen and phosphorous. There is no requirement to monitor or achieve limit concentrations for parameters other than those listed in the Second Schedule.

The Regulations refer to minimum requirements for monitoring for

wastewater treatment plants of 2,000 p.e. or greater. There are no stated requirements for plants less than 2,000 p.e. Section 4.7 of this report sets out recommendations concerning monitoring at all wastewater treatment plants. These recommendations are consistent with the intent of the provisions of the existing Basic Measures.

The monitoring data used in the risk assessment described in Chapter 7

was taken from the EPA biological monitoring stations, which could be 3km upstream or downstream from the discharge point. The Urban Waste Water Treatment Regulations require monitoring in waters where it is expected that a wastewater treatment plant discharge is having a negative impact (refer to paragraph 10.3.4.2). Monitoring, under the Regulations, and targeted monitoring under the WFD operational monitoring programme may give direction as to the most appropriate actions to be taken to achieve water quality objectives.

2. Waste Water Discharge (Authorisation) Regulations (SI 684 of 2007) The Waste Water Discharge (Authorisation) Regulations require the EPA

to attach conditions to agglomeration discharge licenses includin g emission limit values. Emissions for a number of parameters including up to nineteen dangerous substances are being requested in the licence application forms. However, adequate information is not currently available to inform the Water Services Authorities or the EPA concerning parameters which should be controlled in the discharge apart from those listed in the Urban Waste Water Regulations.

10.3.5.4 Supplementary Measures: The following are suggested Supplementary Measures:-

− Investigate the characteristics of treated effluent, in addition to the monitoring requirements under the Urban Waste Water Treatment Regulations e.g. BOD, suspended solids etc.

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− Upgrade waste water treatment plants to remove specific substances known to impact on water quality status.

10.3.5.5 Conclusion

The existing Basic Measures, if fully implemented, will ensure that water quality standards in respect of the parameters stated in the Regulations will be met. However Supplementary Measures may need to be implemented to provide information on other parameters which may be impacting water quality status.

10.3.6 Impacts Evident from Monitoring Data (Transitional & Coastal Waters)

10.3.6.1 Pressure: Monitoring data was obtained for transitional and coastal waters and assessed

with reference to the quality standards required for designated Bathing Waters and Shellfish Waters. If quality standards were not met and there was a treatment plant discharge within 1 km, the discharge from the waste water treatment plant was considered to be impacting on water quality and the water body was determined to be “at risk” (Refer to Chapter 7). There are a small number of sites designated as Shellfish Waters (14). However, new Regulations are pending which may increase the number of designated Shellfish Waters to 64. There is limited monitoring data available for these new ‘candidate’ sites and, therefore, if there is a point source discharge within 1km, these sites should also be considered “at risk” until monitoring data proves otherwise.

10.3.6.2 Suggested Solutions/Actions:

− Provide higher standard of treatment. − Relocate the point of discharge. − Research to determine the extent of impact of point source discharges

on designated Shellfish/Bathing Waters. 10.3.6.3 Basic Measures: 1. Quality of Bathing Water Regulations (S.I. No. 155 of 1992 and S.I. No.

79 of 2008)

The new Regulations shall revoke the 1992 Regulations with effect from 31 December 2014. The Local Authorities are to first identify bathing waters for the purposes of the new Regulations not later than 24 March 2011 and are to provide the EPA with notification of the list. The waters specified in the First Schedule to the 1992 Regulations shall be deemed to be bathing waters identified for the purposes of the new Regulations until such time as the new list of bathing waters has been notified to the EPA. The comments hereunder refer to both the provisions of the existing Regulations and the new Regulations which are relevant to point source discharges.

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Both the existing and new Regulations require that the Local Authority shall take the necessary measures to ensure that the relevant in the Regulations are complied with. The existing standards are set out in the Second Schedule of the 1992 Regulations, which lists 13 parameters. The new Regulations require that the local authority ensures that all bathing waters shall be classified as having water quality status not less than “sufficient” by 15 September 2015. The EPA is to classify each bathing water as “poor”, “sufficient”, “good” or “excellent” in accordance with the criteria set out in Schedule 6 of the new Regulations on or before 15 September 2015 and on or before 31 December in each subsequent year.

Under the new Regulations the Local Authority is to establish a bathing

water profile in accordance with Schedule 1 not later than 24 March 2011 in relation to each bathing water identified. Additionally the local authority shall not later than 24 March 2011 and on or before 24 March in each subsequent year establish a monitoring calendar in accordance Schedule 2 of the Regulations in relation to each bathing water.

The classification of Good Status under the Water Framework Directive in

transitional and coastal waters is not known at the time of this report. It is anticipated that the classification shall be published by the EPA at the end of 2008. If higher standard are set out under the classification than those of existing legislation, then supplementary measures will be required. If the requirements for Good Status under the Water Framework Directive classification match those in the existing Regulations, the implementation of the existing Regulations should ensure the objectives of the WFD are achieved.

2. European Communities (Quality of Shellfish Waters) Regulations (S.I. No. 268 of 2006)

The Regulations require every public authority that has functions, the

performance of which may affect shellfish waters, shall perform those functions to ensure that, as far as practicable, shellfish waters comply with the quality standards specified in Schedule 2 of the Regulations. It is not known how the standards set out in Schedule 2 will compare to the standards required for a classification of Good Status. It is anticipated that the classification shall be published by the EPA at the end of 2008. If higher standard are set out under the classification than those of existing legislation, then supplementary measures will be required. If the requirements for Good Status under the Water Framework Directive classification match those in the existing Regulations, the implementation of the existing Regulations should ensure the objectives of the WFD are achieved.

3. Urban Waste Water Regulations (S.I. No. 254 of 2001)

The Urban Waste Water Treatment Regulations require that all discharges

from agglomerations with a population equivalent greater than 10,000 received secondary treatment. This includes discharges to transitional and

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coastal waters. Secondary treatment is required for discharges to estuaries (transitional waters) for population equivalents of 2,000 and above. Additionally treatment plants are to provide higher standards of treatment than conventional secondary treatment where they discharge into sensitive waters, thereby meeting the required standards for phosphorous and nitrogen concentrations in the discharge. There is no specific requirement to provide secondary treatment for discharges to coastal water from agglomerations below 10,000 p.e. However, the Regulations require that Water Services Authorities shall provide “appropriate treatment” for all discharges. It is at the discretion of the Water Services Authority to determine the appropriate treatment in the context of achieving Good Status in transitional water and coastal waters. Guidance is needed in this area.

4. Waste Water Discharge (Authorisation) Regulations

(S.I. No. 684 of 2007)

The EPA may attach conditions which specify emission limits necessary to

give effect to the requirements of existing environmental legislation to any Wastewater Authorisation Licence for a discharge from a waste water treatment plant or network to a transitional or coastal water. However, the Water Services Authority or EPA may not have sufficient information to determine appropriate emission limit values.

10.3.6.4 Supplementary Measures Transitional and coastal water bodies have been designated at risk due to non-

compliance with existing water quality standards as being indicative of impacts from point source discharges. Full implementation of the existing Regulations will secure compliance with the Bathing Waters and Shellfish Waters Quality Standards. However, there are no specific actions stated in the Regulations and information may not be available to advise the Water Services Authorities on the actions necessary to comply with the standards. A default action may be to provide a minimum standard of treatment (i.e. secondary) at all waste water treatment plants which are negatively impacting on transitional and coastal waters. Alternatively, install treatment which will achieve the standards in the discharge (e.g. UV treatment in the case of Bathing Waters).

The possible Supplementary Measures are summarised as follows:-

− Install secondary treatment as a minimum for all waste water treatment plants discharging to water bodies “at risk”.

− Install UV or similar treatment, in addition to secondary treatment to

waste water treatment plants discharging to “at risk” waters and at treatment plants discharging within 1km of a designated Bathing Waters or Shellfish Waters where no monitoring data is available.

− Research to determine the extent of impact of point source discharges

on designated Shellfish/Bathing Waters

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10.4 Summary of Measures

10.4.1 Basis Measures and Actions Required Under the Basic Measures

All of the Basic Measures as defined in Article 11 and Annex VI of the Water

Framework Directive must be implemented in full. In some instances the Water Services Authorities are not implementing the Basic Measures fully. Consequently, the Water Services authority should address any deficiencies in the implementation of the Basic Measures. The MIR POMS study has identified some actions that would assist in the fulfilment of the Basic Measures. The following is a non-exhaustive list of Basic Measures which have been identified as having provisions of relevance to point source discharges. The list is not to be considered definitive.

1. The Urban Waste Water Treatment Directive (91/271/EEC)

Urban Waste Water Treatment Regulations (S.I. No. 254 of 2001)

Actions for Water Services Authorities:-

− Install facilities at waste water treatment plants to measure the influent loading.

− Keep and update a register of plant capacity.

− Review conditions of section 16 licenses with the aim of reducing plant

loading.

− Investigate connections to the collection system to identify unlicensed non-domestic uses and take actions to put licenses in place.

− Limit or cease the direct importation of materials to a treatment plant

where the plant is at capacity.

− Monitor the receiving waters at all water bodies at risk. 2. The Dangerous Substances Discharges Directive (86/280/EEC)

Waste Water Discharge (Authorisation) Regulations (S.I. No 684 of

2007) Actions for EPA:-

− Take into consideration the assimilative capacity of the receiving waters in the setting of discharge license conditions..

− Include in the conditions attached to licenses and certificates

requirements for flow monitoring and influent and effluent sampling consistent with the recommendations contained in Chapter 4 of this report.

− Include in the conditions attached to licenses that a register of plant

capacity is put in place and maintained.

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− Include in conditions attached to discharge licenses the requirement to monitor the receiving waters at waste water treatment plants discharging to water bodies at risk.

3. The Bathing Water Directive (76/160/EEC)

Quality of Bathing Water Regulations (S.I. No. 155 of 1992 and S.I. No.

79 of 2008)

4. Directive 79/923/EEC of October 1979 on the Quality Required for

Shellfish Waters

European Communities (Quality of Shellfish Waters) Regulations (S.I. No. 268 of 2006)

5. The Integrated Pollution Prevention Control Directive (96/01/EC) Actions for EPA:-

− Review licensed discharges to river water bodies considered to be at risk due to lack of assimilative capacity in the receiving waters or where there is a deterioration in status within 3km of the point of discharge.

− Review licensed discharges to transitional and coastal water bodies

within 1km of a bathing water or shellfish water where the receiving water body is “at risk”.

10.4.2 Suggested Supplementary Measures The following is a list of Supplementary Measures which may be adopted as

part of the Programme of Measures in relation to point source discharges.

− Investigate the extent of use and impact of under-sink food waste disintegrators (FWDs) and introduce controls where appropriate.

− Investigate fats/oils/grease (FOG) concentration in the influent and

require FOG control systems e.g. grease traps for activities which result in FOG entering the collection system (bye-laws, licence conditions).

− Initiate a public awareness campaign aimed at reducing pollution

loading entering the collection system.

− Investigate the need to introduce further controls on phosphorous in detergents additional to the voluntary code employed by the Irish Detergent and Allied Products Association, including the possibility of mandatory/statutory limits.

− Optimise operation and performance of existing wastewater treatment

plants.

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− Assess the assimilative capacity of receiving waters using a systematic approach such as the application of a decision support tool like SIMCAT

− Relocate the point of discharge.

− Investigate the characteristics of treated effluent, in addition to the

monitoring requirements under the Urban Waste Water Treatment Regulations e.g. BOD, suspended solids etc.

− Upgrade waste water treatment plants to remove specific substances

known to impact on water quality status.

− Install secondary treatment as a minimum for all waste water treatment plants discharging within 1km of a designated bathing water or shellfish water.

− Research to determine the extent of impact of point source discharges

on Shellfish/Bathing Waters

− Install UV treatment or similar type treatment, additional to secondary treatment, at all waste water treatment plants discharging within 1km of a designated bathing water or shellfish water.

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Appendix A

Position Paper on Flow Monitoring and Sampling Facilities at Municipal Waste Water

Treatment Plants (Volumes 1 & 2)

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Appendix B

Reports on Characteristics of Urban Waste Water

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Appendix C1

Pilot Project for Cork City and County Area - Population Forecasting Methodology

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Appendix C2

National Population Projections and Regional Population

Targets 2006 – 2020

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Appendix C3 Population Projection Results for 2015

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Appendix D

SIMCAT Model for SWRBD – Final Report

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Appendix E

Water Bodies Risk Register