Whitstable Town Hall Meeting -

Cromwell Road Embankment Works

Thursday 3rd May 2012 – St Marys Hall, Whitstable – 18:30

Rev Paul Wilson and John Burrows

Before We Start…….

• Fire Evacuation Procedure

• Fire Exits

• Mobile Phones

• Any Members of the Press ?

• Filming

Agenda

• Residents Concerns – Julie Wassmer

• Geotechnics Report – Simon Abbott

• Track Geometry – Jordan Faulkner

• Environmental Issues – Glen Brown

• Work Scope and Method – Martin Pope

• Notification Policy & Lessons Learnt – Glen Brown

• Summary

• Questions Session

Resident’s Concerns and

Objections

Clay Embankments and the

Problems Associated with

Vegetation

Simon Abbott (BEng), CGeol, FGS, – Senior Asset Engineer (Geotechnics)

Earthwork Assets

Soil Cuttings

Embankments

Rock Cuttings

Three principal geotechnical asset types we are responsible for;

Continued process of examination, maintenance, investigation, assessment and remediation

Geological Context & Construction

BGS Swell-Shrink Potential Map

Sensitivity to Moisture Change•Gault•London Clay •Weald Clay

1960’s compared to 2012

Historically little vegetation aside from grass and low scrub on embankments and cuttings

1960’s compared to 2012

Car parks highlighted for point of reference

Trees – good or bad?

Cuttings – bad

Trees – good or bad?

Chelsfield Cutting

Trees – good or bad? Embankments..

It is misunderstood that mature vegetation only has positive impacts on slopes.

High water demand trees have a detrimental effect on the condition of particular embankments (next slide)

Tall trees impose high loads as a result of wind loading.

Leaf fall

Signal Sighting

Modern Understanding of Geotechnics

Land take pressures during railway construction mean assets are typically over steep

Settlement & Heave up to 50mm between summer and winter.

Permanent outward spreading of embankment

Leading industry research

15

Soil Moisture Deficit (SMD)Ashford’s Square 174

Faversham’s Squares 163 & 164

SMD = Amount of rainfall (mm) that the ground can absorb before reaching saturation.

SMD of 0 = saturated

SMD of 200 = dry

Rate of SMD rise in Morec Square 163

0

50

100

150

200

250

300

350

01-Jan 01-Feb 01-Mar 01-Apr 01-May 01-Jun 01-Jul 01-Aug 01-Sep 01-Oct 01-Nov 01-Dec 01-Jan

20092010

20112012

SMD Chart 163 VIR

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Gillingham to Herne Bay

How the line side vegetation should be

We always endeavour to leave trees at the toe

Remedial scheme necessitated removal of trees on inner verge.

What Happens if we don’t manage the vegetation on our clay embankments?

Serviceability and Delayed Failure

Delayed failure is associated with long term shrink-swell induced by vegetation

References:

• Briggs, K (2010). Charing Embankment: Climate Change Impacts on Embankment Hydrology. Cooling Prize 2010 Winning Submission.

• Loveridge, F.A et al (2010). The impact of climate and climate change on UK Infrastructure slopes.

• Smethurst, J.A etc al (2005). Seasonal changes in pore water pressure in a grass covered cut slope in London Clay.

• O’Brien, A.S.O et al (2004). Old Railway Embankment Clay Fill – Laboratory Experiments, Numerical Modelling and Field Behaviour.

• CIRIA Special Publication C592 (2003). Infrastructure Embankments – condition appraisal and remedial techniques.

Track Geometry

Jordan Faulkner – Track Maintenance Engineer (Faversham)

Network Rail Standards – Track Maintenance

Working to Network Rail standards that are applied nationally for inspection and maintenance of track. The standard specifies:

• Minimum frequencies for inspections.• Processes for carrying out inspections.• Details those track geometry faults which require action.

Good track geometry

Whitstable track geometry

• Shows vertical and lateral rail alignment.

• Super Red eighth = eighth within in maximum SD band.

• Eighths within maximum SD band pose an increased risk of an incident.

Whitstable track geometry

Standards state:

•Engineers must use other asset information and/or arrange more detailedexaminations where needed to identify root causes.

• Standards require that we take appropriate action to improve track geometry quality by tackling the underlying causes.

• Also faults shall be repaired before they affect the safe performance of the track.

Track Geometry

Photos from 2011

Clay Bank Vegetation Management

Ashford to Maidstone line - Hollingbourne Station

Ashford to Maidstone line - Charing Station

Evidence of TQ affected by trees on Ashford to Hastings line.

Individual Trees

Track - Summary

Repeat maximum SD (Super Red) track geometry• Increased safety risk. • Increased inspection frequencies.• Condition of track speed restriction for 13+ weeks in summer 2011.• There is a limit to work that can be completed in summer due to the risk of track buckles.• Already undertaking maintenance work 3 times more frequent than similar track.• Large number of speeds across East Kent in 2011.• Component deterioration – increased maintenance – component deterioration.

Date 00.00.00 32

Environmental Concerns and Summary of Vegetation Management

Angela Cruickshanks – Infrastructure Maintenance Environmental Specialist (BSc/MSc Environmental Consultancy, AIEMA)

Martin Pope – Infrastructure Maintenance Programme Manager

Presentation title to go here 33

Environmental Concerns

• Pre-work survey completed by Network Rail to identify if any protected areas in the vicinity or any protected trees are present

• Daily site inspection recorded by the contractor to identify any nesting birds in the area of work

• Risk of nesting birds identified by Network Rail in the work package plan and provided to the contractor

• Consultation with Natural England to advise on the scope of the works

• Site walkouts completed to identify nests by the Network Rail Environment Specialist, Lineside Engineer and Programme Manager

Environmental Legislation/Mitigation

• Under the Wildlife and Countryside Act 1981, all wild birds, their eggs and nests are protected

• It is an offence to intentionally take, damage or destroy the nest of any bird while in use or being built.

• There is no reference in the Wildlife and Countryside Act 1981 to specific dates when vegetation work cannot be carried out as birds potentially nest all year round and is dependant on climate

• Contractor advised to create an exclusion zone of 2m surrounding any potential nests identified as per the company corporate guidance

Proposed Plan

• Phase 1 - Remove all younger Sycamore re-growth close to the lineside first and any dense shrubbery which restricts access to larger trees

• Phase 2 – Re-Survey the large Sycamore trees for nest which may be covered by the ivy. NB The ivy indicates poor health of the trees and some trees identified as decaying

• Any larger trees where birds are not nesting shall be removed in accordance with the specifications discussed.

• A proposal to use other Network Rail land to create a dense woodland to compensate for the woodland habitat removed at Whitstable in a habitat trading scheme

Network Rail’s ongoing Vegetation Management

• In addition to the specifications already discussed there are a number of other specifications where Network Rail are required, in accordance with Company Standards, to proactively manage vegetation on Network Rail controlled infrastructure. One such specification is to clear, up to 5 metres laterally from the running line, maintain clear of all woody vegetation. The area vertically above shall also be maintained clear of all vegetation. This excludes general ground and scrub clearance for the safe removal of trees on embankments.

The Network Rail

Pre Notification Policy

Glen Brown – Maintenance Protection Co-ordinator

Pre Notification of Works Policy

• Maintenance is the general day-to-day upkeep of the railway which keeps the trains running, for instance looking after tracks, signals, power supply and vegetation. Engineering is the larger scale infrastructure work, for example track replacement and upgrade works.

• When we are planning engineering works near residential areas, we aim to send letters to local people 10 days before the work begins. The letters explain what we plan to do and when we expect the works to start and finish.

• For maintenance work (such as emergency repairs or general up-keep), it is not possible for us to tell the people who live nearby. This is because maintenance work takes place every day and night of the year on the railway all over the country which makes it impractical to give advance notice to all the people affected by every job.

Pre Notification of Works Policy

• The vegetation works carried out in the Whitstable area are classified as maintenance works. Due to the timescales involved, letter drops were done in good will at Cromwell Road several days before work was due to start on this side of the railway.

• If we can, we will work on the plants and trees near the railway during the day between Monday and Friday, but sometimes we have to work at nights or weekends so that we can keep our staff safe and the trains running.

• If we are working in an area for a prolonged period, we try to let our neighbours know through letter drops. We will also contact the appropriate local authority informally and if necessary submit a formal activity and noise application to obtain consent.

Lessons Learnt –

Cromwell Road Tree Clearance

Glen Brown – Maintenance Protection Co-ordinator

What we could have done much better…

• Network Rail standard letter templates were not used as the contractor was asked to manage this process without full guide lines on our process being provided.

• Our contractors have been fully re-briefed on the NR pre-notification policy and the new updated templates to use.

• Letters should have been more descriptive of the works being carried out so as to avoid confusion that all trees were being removed from the embankment.

• The words “Vegetation Clearance” are open to interpretation and very rarely mean all vegetation. These have been changed to be more descriptive on our new template.

and how we are making it better?

• Letters should have been distributed to affected residents 10 days in advanceof the works through our postal service – Via post.

• All larger scale vegetation works are to be notified to the MPC so that letters can be sent out 14 days in advance as we do with all engineering projects or road closures etc.

• Managing the publics expectations when stopping works was not handled well.• Information given to the public was reactive and did not explain that the site must by law be left safe and that this may require a bit more time of noise to achieve.

Questions & Answers

• THANK YOU FOR ATTENDING AND GOODNIGHT.