UNEP-DHI Water Quality Webinar Series

Water Webinar #2Water Quality: The Key Challenges

Facilitator: Gareth James Lloyd Technical Support: Maija Bertule

www.unepdhi.org

Contents

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• Why is water quality essential for human health and wellbeing?

• In which ways do natural processes and human activities impact water quality?

• Water scarcity and Climate Change – impacts on Water Quality

• Additional questions and answers

Why is water quality essential for human health and well-being?

Claus JørgensenMicrobiologist

Hygiene and assessment of health risks associated with human contact to drinking water, bathing water and waste water

“The global crisis in water consigns large segments of humanity to lives of poverty, vulnerability and insecurity”. (Human Development Report 2006, UNDP)

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• Close to half the people in the developing world are suffering diseases associated with inadequate provision of water and sanitation. (Human Development Report 2006, UNDP)

• 443 million school days are lost each year due to water-related diseases. (Human Development Report 2006, UNDP)

• Women shoulder the largest burden in collecting drinking-water (WHO/UNICEF 2010)

MDG: The JMP drinking water and sanitation ladders.

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“Universal access to basic social services - education, health care, water supply and sanitation, and public safety - enhances resilience” (Human Development Report 2014, UNDP)

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• In 1990, 76% of the global population had access to improved drinking-water; in 2012 this figure had reached 89% (WHO 2014)

• 1.9 billion people worldwide use either an unimproved source or an improved source that is faecally contaminated (WHO 2014)

“Universal access to basic social services - education, health care, water supply and sanitation, and public safety - enhances resilience” (Human Development Report 2014, UNDP)

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WHO 2014

An example of improved but contaminated drinking water.

Slum area in Dhaka, Bangladesh.

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Reducing diarrhoeal diseases by improving water quality?

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(Source: Preventing diarrhoea through better water, sanitation and hygiene. WHO 2014)

• There has been an increase in the coverage of improved sanitation from 49% of the population in 1990 to 64% in 2012 (WHO 2014)

• Almost 2 billion people have gained access to an improved sanitation facility (WHO 2014)• 2.5 billion people (67% of whom live in Asia) still use unimproved sanitation facilities

(WHO 2014)

“Universal access to basic social services - education, health care, water supply and sanitation, and public safety - enhances resilience” (Human Development Report 2014, UNDP)

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WHO 2014

Reducing diarrhoeal diseases by improving sanitation

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Protecting whole communities from faecalexposure, may provide significant additional protection from diarrhoea.

Handwashing with soap is expected to reduce diarrhoeal disease with 23%

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Drinking water, sanitation and hygiene should be improved in concert (WASH)

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WASH and water resource management also reduce

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• Undernutrition• Schistosomiasis• Nematode infections• Malaria• Denque• Japanese encephalitis• Drowning• Arsenicosis• Fluorosis• Methaemoglobinaemia

Infection and illness after direct or indirect exposure to water of a poor quality

− Drinking water and sanitation− Surface water− Recreational water− Irrigation water− Flood water

Why is water quality essential for human health and well-being?

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1.700 iron men was swimming in sewer water (Politikken, 20. Aug)

Flood water: Estimated average risk of cholera for children living in slum in Dhaka, Bangladesh, by QMRA

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• Hydraulic sewer and surface model the fraction of raw waste water on the surface

• Pathogen concentration in raw waste water• Estimations of exposure• Dose response relation

Dhaka City, BangladeshMark et al. 2015. J. Flood Risk Management

Thank youClaus Jørgensen, DHI

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Name: Jørgen Krogsgaard Jensen

Title: Biologist (M.Sc.)

Bio: Ecological and water quality studies in rivers, reservoir and lakes. Pollution load estimation. Modelling hydraulics, water quality and ecological processes.

Natural Factors

• Meteorology (sun, precipitation, wind, temperature)

• Hydraulics

• Bathymetry/morphology of water body (depth, size …)

Human Activities Pollution (domestic, industrial, smaller commercials ...)

Damming

Channelization/Navigation/Dredging

Agriculture

Aquaculture

Natural resource utilization – ex. water transfer

…and a lot more…Climate Change

Pollution Nutrients from

Agriculture, aquaculture, domestic, Industries …

->

Eutrophication

Pollution

Delhi

Organic substances Oxygen depletion

…

Heavy metals

Harmful Organic Compounds

Radio Nuclides

…

Damming Water transfer

Irrigation

Drinking water supply

Hydropower

Damming - selected impacts Changing hydrographs downstream Changing up- and downstream hydraulics Disturbing migration of fish and other aquatic

organisms Trapping sediment and nutrients Create sediment hungry rivers – increase erosion

downstream Eutrophication in reservoirs – organic load

downstream Impact on fish spawning sites Changing condition in riparian wetlands ....

Inland water ways – Navigation –Regulation of Rivers Canalization – smoothing curves Reducing dynamic on the rivers Removing sandbars - dredging Bank erosion- bank protection Spill of sewage, oil etc. Closing side branched Changing water levels Reducing connectivity to riparian wetlands …

How to distinguish between natural induced changes and impact from human activity

Year to year variation due to metrological condition can it make difficult and challenging

Some impact from human activities are obvious – for exampleoxygen depletionreduce flow as consequence of water utilizationacute toxic impacts

Others requires good data sets and often longer time series – for examples changes in

eutrophication levelsfish stockbiodiversity…

How to distinguish between natural induced changes and impact from human activity

• For detailed analysis information are required about changes in• Natural driving forces ( primarily Metrologic)• Human induces pressures ( Pollution, water abstraction,

physical changes …)

• Statistical analysis (trend analysis, multi variance analysis, etc. )

• Modelling analysis that include pressures and other diving forces as input function

Flow Flow

Thank you

Water scarcity and Climate Change – impacts on Water Quality Jesper Goodley Dannisøe, Senior Project Manager Title: Senior Biologist Bio: Large-scale infrastructure, water quality, EIA and monitoring

Contents

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Water scarcity and Climate Change – impacts on Water Quality: Setting the scene: • Some regions may experience more rain • Some regions will experience less rain • The rainfall may change pattern and season!

Temperature and precipitation; present and future

What can change the water quality?

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• Changes in rain pattern (Drizzle / heavy down pour) • Frequency between rain fall • Changes in urbanisation and treatment of waste water • Agriculture and use of pesticides and fertilizers

Drizzle or Heavy rain!

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Item Drizzle Heavy rain

Surface run-off √ Storm water overflow √ Reduced wastewater treatment capacity

√

Soil absorption capacity √ (√)

Frequency between rain events

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• Build-up of waste on streets, gutters and land • First-flush; the most contaminated water during the rain event

Changes in the Urban landscape!

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• City development often takes place without development of infrastructure:

• Storm water systems • Retention systems • Street cleaning • Wastewater treatment

Wastewater treatment?

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Data from Sustainable development goals: Goal 6: Ensure access to water and sanitation for all: • 2.4 billion people do not have access to sanitation systems • >80% of the worlds wastewater is discharged un-treated to the

environment

Agriculture; Pesticides and fertilizers

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• Drainage of agricultural lands washes out pesticides and fertilizers • Pesticides used uncontrolled and often with no knowledge about

dosage and consequences

Water scarcity

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Climate changes will exercebate water scarcity as a whole: • Increase in abstraction for drinking water • Increase in water for agriculture • Increase in water for industrial production

Can we counter-act on water scarcity?

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• Stop leakages in water supply systems (world-average loss = 40-50%)

• Change crops to less water demanding types

• Optimise on water used in the industry • Put a price on water, which reflects the

actual cost of water and remove subsidies (for non-poor people)

Harvest all available water

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• Harvest and store rainwater • Use surplus water for recharging groundwater • Use treated wastewater as drinking water, production water and

water for other purposes

Awareness, awareness, awareness!!

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Climate changes may be the smallest cause of impacts on water quality!!

Thank you Jesper Goodley Dannisøe, jda@dhigroup.com

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Additional Questions

Thank you for attending WQ Webinar #2

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− Questions/comments to Maija Bertule mabe@dhigroup.com− Webinar recording and slides on YouTube (UNEP-DHI) and

http://www.unepdhi.org/wq-webinars− Link to recording and Feedback survey in follow-up email

Next webinar (#3)− October 14th: “Frameworks for Water Quality Governance”− Registration:

https://attendee.gotowebinar.com/register/4779487255423060225