Our position

Stannon Lake

Where does our water come from?

Surface water sources, such as reservoirs and river intakes, provide approximately 90% of the South West Water region's water supply. Local reservoirs are supported by three large strategic reservoirs: Colliford, Roadford and Wimbleball.

In the South West Water area, water bearing rocks (aquifers) are limited. Therefore groundwater sources, such as springs, wells and boreholes, only account for 10% of our water supplies. These are located mainly in East Devon.  This is different to other regions - for example, Wessex Water gets 75% of its water supplies from groundwater.

During the winter months, when river levels are healthy, we abstract water from rivers with the reservoirs providing back-up supplies. The river and reservoir systems are linked together by a network of pipes, which enable us to transfer water around the region.

Initially we make use of the 18 smaller, local reservoirs. When the storage level in these reservoirs drops to a certain level, we make use of our large, strategic reservoirs, Colliford, Roadford and Wimbleball.

By using the network of pipes we are able to move water around to balance dry periods in one part of the region with wetter periods in another. We are also able to pump water from rivers into our reservoirs, rather than waiting for them to refill naturally.  

Current situation

Despite the recent dry weather, South West Water continues to maintain a good water resources position.

Total reservoir storage is currently 89% (90% this time last year).

The early months of 2012 were dry with February receiving only 39% of the long-term average (LTA) rainfall and March receiving only 32%.  However, the South West received 265% of its LTA rainfall in April.  The wet weather continued throughout the rest of 2012, with the region receiving more than 200% of its long-term average rainfall in both June and July and around 180% of its LTA rainfall in both August and December.

January 2013 continued the trend of above-average rainfall and received 113% of the long-term average, but February 2013 was the first month since September 2012 to receive below-average rainfall at only 60% of LTA for the South West.  March saw return to wet conditions with rainfall at 111% of LTA, followed by only 66% of LTA in April and average precipitation at 105% of LTA in May. 

We are continuously monitoring our water supplies and operate our water resources system accordingly.

2012 was our 16^th consecutive year without water restrictions.

We have no plans to impose any water restrictions or to apply for Drought Permits or Drought Orders.

Changes since 1996

Since 1996 (the last year the South West Water region had water restrictions):

• We have reduced leakage from our network of pipes by 40%
• 72.5% of domestic customers now have meters (compared with 8% in 1995)
• The region is using 14.8% less water

We have also invested heavily in the region:

• We have increased the capacity of our water treatment works
• We have improved the efficiency of our works so we use less water in our treatment processes
• We have improved our ability to move water around the region
• We have invested in pump storage schemes at Wimbleball and Colliford
• We have two new reservoirs in Cornwall, Park and Stannon.

In recent years we have made a number of investments including:

• Installing new distribution pumps in East Devon to optimise our use of boreholes
• Installing lime dosing at Northcombe Water Treatment Works, near Okehampton, to reduce the minimum amount of water the works will produce
• Remotely operating Wistlandpound reservoir
• Installing a variable speed pump at Kennal Vale intake, which supplies Stithians with river water

Updated: 18 June 2013