Duddon Water Abstraction.United Utilities have a licence to abstract water from the Duddon.The amount that can be abstracted depends on water flows, and the criteria are quite complex. In addition Seathwaite Tarn, high up on the west side of the Coniston range, and at the top of Tarn Beck, is used to provide some of the water abstracted, and also for compensation flows when the main river flow falls below a certain level. The following was provided by United Utilities. UU's abstractions from the Duddon are governed by a complex set of rules relating to the flow in the river (at the point of abstraction) and how much water is released into the river upstream from Seathwaite Tarn reservoir. In simple terms, releases are adjusted from Seathwaite Tarn reservoir to match the volume of water being abstracted at any given time, so as to protect natural river flows. In terms of actual abstraction, UU generally abstracts between 12 and 14 million litres per day (= 2.6 to 3.1 million gallons per day), depending on demand in the Barrow area. Abstraction can vary from between 6 to 22 million litres per day (1.3 to 4.8 million gallons per day), although abstraction at the higher rates is only needed for short periods to meet peak demand situations in hot, dry weather and is dependent on sufficient river flows to comply with the licence conditions. During 2005, abstraction averaged 12 million litres per day (2.6 million gallons per day). The maximum abstraction was 17 million litres per day (3.7 million gallons per day) over a one week period and the minimum was 8.6 million litres per day (1.9 million gallons per day). As with most of our water sources, abstraction has reduced over the last 15 years as demand for water and leakage levels have reduced, as shown below: 1990 abstraction averaged 21 million litres per day (4.6 million gallons per day) 1997 abstraction averaged 16 million litres per day (3.5 million gallons per day) 2005 abstraction averaged 12 million litres per day (2.6 million gallons per day) (NB. to convert from million litres per day (Ml/d) to million gallons per day, divide by 4.546) If you are interested you can see the full licence here Duddon Abstraction License (pdf document) 
View down the Duddon Valley from Grey Friar, with Seathwaite Tarn in the foreground. This provides water for abstraction lower down, and also compensation flows for the main river during drought. Crake River FlowsThis graph shows the flows measured by the hydrograph on the River Crake at Low Nibthwaite over a 5 year period. Crake River Flows (pdf document)
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