Water Resources for Hertfordshire

1. Water Resources for Hertfordshire Alex Back Hydrologist 28th October 2010

2. Who are Veolia Water? • 3 Water Companies, and have been part of an international water supply company since 1989 • Water Only • Population 3.5 million • Supply 900 Mld Average and 1210 Mld at Peak • Mains 16,172 km • We have duty to meet customer demand Central East South East

3. New towns were built in the 50s and 60s; Welwyn Garden City, Hatfield, Roydon, Stevenage and Letchworth Little consideration was given to the effect of these new towns on the environment when they were built and local groundwater was developed Groundwater abstraction affects river flows in Hertfordshire especially during times of low groundwater levels or drought Groundwater sources are being used to their full capacity during times of peak demand providing local water for local people and constitutes 60% of our supply Groundwater is the best quality and lowest cost source of water in Hertfordshire and helps to keep customer bills as low as possible We also import 10% of our water from Anglian Water’s reservoir at Grafham but this is expensive and of lower quality and the remaining 30% comes from the river Thames Issues for Water Supply in Hertfordshire

4. Future housing growth and population growth • It is predicted that 200,000 new people will move into the area by 2040 • This has been allowed for in our WRMP by adopting a twin track approach of new resources and demand management, but the majority of these will not be required before 2035 • EoE plan no longer exists, and we now have to seek the latest situation on housing growth from the Local Authorities

5. Chalk rivers are recognised as a rare and valuable habitat Low flows (following winter droughts) a major concern Flooding and climate change are also significant impacts We have been working with the EA since 1990 and 3 of the original 1991 ALF projects on the Hiz, Misbourne and Ver were implemented in AMP2 (1995-2000), Major NEP programme, based on RSA work (2000-2015) currently investigating Misbourne, Ver, Colne and Rib Sustainability changes already notified for post AMP5 (2015+) More to come, and working with the EA to identify these, but it is difficult and expensive to replace water Cost – benefit analysis is difficult and in surveys, our customers showed a low preference to pay for environmental issues Environmental Issues

6. Pollution Risks • Major issue, many sources impacted by pollution • Nitrates, pesticides, hydrocarbons, legacy landfill and industrial sources, turbidity & microbiological • Unconfined Chalk, provides limited protection and rapid flows means threat of pollution constant • To protect the quality of the water we supply, pollution is normally managed by installing treatment, blending or sometimes abandonment/replacement of source

7. Pollution Risks • Investigation and removal of source of pollution, especially in groundwater is very difficult and expensive, legally complicated and subject to long time delays the “polluter pays” principal is not often the end result • We work hard to prevent pollution and undertake catchment surveys and risk assessments to identify potential threats • These feed into Drinking Water Safety Plans and catchment management activities

8. Thank you for your attention Any questions?