Abstraction and low flows

Water resources were stable in 2009, after the winter of 2008/09 saw a greater-than-normal 'recharge'. This occurs when rainwater makes its way down through the soil, replenishing groundwater, which in turn feeds rivers and borehole sources.

Throughout 2009, we continued with our twin-track approach of managing demand for water and, where necessary, developing new sources, as reflected in our revised draft Water Resource Management Plan.

Abstraction

About 77 per cent of the water we take from the environment comes from rivers, while the remaining 23 per cent comes from groundwater sources. The removal of this water – known as 'abstraction' – is regulated by the Environment Agency through its abstraction licensing process.

In 2009, we achieved 99.90 per cent compliance with our daily licence limit and 100 per cent compliance with our annual limit.

Low flows in rivers and at key sites

There are some areas where abstracting water can contribute to low flows in rivers, which can be ecologically damaging.

We are continuing to work on a programme, agreed with our regulators, to limit abstraction and implement schemes to alleviate low flows on stretches of river identified to be suffering from low flows.

We are undertaking new investigations at key sites where it is thought that our abstractions may be causing problems under low flow conditions, including the tidal estuary of the River Thames in London.

Low flow investigations

By the end of 2009, we completed and reported on all nine investigations requested by the Environment Agency, and originally agreed with Ofwat as part of our business plan for the period 2005 – 2010.

For three of these investigations, we are now performing an 'options appraisal', to look at the best possible solutions to the identified need. These cover Sulham Brook, near Reading, the River Og, near Marlborough, and water courses near Oxford, including the Seacourt Stream.

We have also initiated a further four investigations to look for possible impacts of abstraction on the River Wye, near High Wycombe, the Upper Wandle and Waddon Ponds (south-west London), the Letcombe Brook (Wantage), the Royal Brook (Stroud) and the Lower Thames.