Reservoir levels and rainfall figures

Last reviewed:

We had 41mm of rainfall across our area from 1 to 28 February 2016, which is 79 per cent of the 131-year monthly average.

Rainfall in the last year

The graph below shows the rainfall over the last year and percentage increase and decrease against the monthly average.

Where our water comes from

Across our region, we take about 65 per cent of our source water from rivers, in a process called abstraction. We then store this in large, open reservoirs (known as surface reservoirs) before putting it through our treatment process to turn it into drinking water.

The remaining 35 per cent comes from underground boreholes, from which we pump water which has originally fallen as rain and sunk down into the ground. These supplies are referred to as groundwater.

Find out more about where our water comes from

February reservoir and water levels

The diagram below shows the rainfall and levels of water in the rivers, reservoirs and underground in our area, for the last month.

Water situation summary February 2017

  • Groundwater levels rose at many boreholes during the month except in the Cotswolds where levels started going down. At the end of the month most sites were at Below Normal levels for the time of year.
  • On 28 February the Thames Regional SMD total was 0mm which is slightly wetter than the expected 3 mm.
  • Flows were still below their long term averages for most of February. The Teddington Target Flow remained at 800 Ml/d during the month in agreement with the EA
  • Reservoir storage on the 28 February 2017 for London as a whole was 94% (Thames Valley 98% & Lee Valley 75%) and Farmoor storage was 98%.