South West reservoir levels are well down on the same period last year

The agency says England and Wales have experienced the second driest period since 1921.

While public water supplies have not yet been affected, there have been reduced river flows in the South West and reservoir levels have dropped significantly.

The agency says the extra rainfall needed to avert drought measures in the South West will need to be persistent and widespread.

The water levels in the South West's main reservoirs are well down on the same time last year.

We want sustained, fairly low-level rainfall over a long period of time to enable the water to go into the groundwater systems, fill up the reservoirs and increase the flow in the rivers Alan Burrows, Environment Agency

The region's biggest reservoir, Roadford in Devon, is only 50.4% of its total capacity at the moment, compared with 89.2% at the same time last year.

Colliford, near Liskeard, is 57.8%, compared with 68.8% in November 2002, and Stithians in Cornwall is 45.7%, as opposed to 75.1% 12 months ago.

The biggest decreases are at Wimbleball, on the Devon-Somerset border, and Burrator in west Devon.

Wimbleball was 95.1% full in November 2002, but is now only 31.7% of its capacity, while Burrator - one of the region's smaller reservoirs - is 36.3% full, compared with 100% last year.

The total storage capacity for South West Water's reservoirs is at 49.3%, compared with 86.3% 12 months ago.

Increase flow

Alan Burrows, the Environment Agency's Devon area environment manager, said: "We don't really want to see heavy rainfall in short bursts.

"It falls on the land, runs off into the rivers and then out to sea.

"We want sustained, fairly low-level rainfall over a long period to enable the water to go into the groundwater systems, fill up the reservoirs and increase the flow in the rivers."