Serving parts of North West London and the Home Counties.

Our Water Resources


Last update: 3 July 2017

Ground water levels: below average

We depend on winter rainfall for the water we supply to you. Since July 2016 there has been low rainfall, and our groundwater resources remain well below average. This is important, as 60% of your water we supply to you comes from these underground sources.

We are asking customers to save water to minimise the possibility of water restrictions this year... if we all save a little, we’ll all save a lot! Click here for useful water saving tips and free devices.

We welcomed the rainfall in May and June, which benefited the environment and helped reduce the demand for water but this was limited compared to the low rainfall over the last 10 months. Also, usually aquifers only fill up from rainfall during autumn and winter when there is less plant growth and evaporation.


Our current water levels

Below is a diagram of our current water levels



Rainfall levels: still below average and potential dry summer on the way

The below average rainfall means we have not seen the usual rise in groundwater levels that we would usually expect and some rivers across our region have seen flows decrease.

The Met Office long range weather forecast has also indicated that the next few months are likely to continue with above average temperatures and below average rainfall.

We continue to monitor the situation closely with clear plans in place to make sure we’re fully prepared, should the dry weather continue through the autumn and next winter.

In the meantime, we are encouraging our customers to save water to help preserve supplies.

Here is a graph showing the average rainfall levels for the past year


To find out more about our water resources and the water cycle click here



Doing a little, saves a lot!

We offer free practical advice and water saving devices to help you save water, energy and money. If you use less water you are likely to save on your energy bills too!

According to the Energy Saving Trust, approximately 21% of household heating bills relate to heating water for showers, baths and hot water taps. This does not include kettles, washing machines and dishwashers, which use additional energy.

  • By turning the tap off when brushing your teeth, you can save over 6,500 litres of water per year.

  • A bath can use up to 100 litres, a shower uses about a third of this. However be aware - modern power showers can use more water than a bath if you shower for more than 5 minutes.

  • Choose drought resistant bedding plants such as Alyssum, Geraniums, French and African Marigolds and Petunias or plant perennials such as Aquilegia, Campanula or Heuchera.

  • A garden hose or sprinkler can use almost as much water in an hour as an average family of four uses in one day. Try and use a watering can instead to water your garden.

  • Make the most of the rain that falls during this dry period and install a water butt to help water your garden.


Click here for water saving tips and free water saving devices




What we’re doing

We operate in areas which are designated as suffering from serious water stress* and we face a growing population. We need leave more water in the environment, whilst making sure we have enough water. We can only do this by working in partnership with our customers to reduce demand for water.

Over the last two years we have made significant investments in driving down leakage whilst helping our customers use less water. This includes:

  • Offering practical help to our customers to save water, energy and money through our FREE Home Water Efficiency Checks with every meter fitted

  • FREE water efficiency devices offered to all our customers

  • Driving down the level of leakage on our network beyond the target set by our regulator, Ofwat

  • Increasing our investment to renew our network to help prevent leaks and bursts.

  • Our Education Team engages with thousands of students a year in schools and at our Education Centre in Bushey to enrich school curriculums and promote water efficiency.

* The Secretary of State for the Environment, Food and Rural Affairs under Regulation 4 of the Water Industry (Prescribed Conditions) Regulations 1999, as amended.

To find out more about our water saving programme, please visit

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