Abberton Reservoir

Abberton Reservoir

Site of Special Scientific Interest
View from south-west
Location	Essex
Grid reference	TL970180
Interest	Biological
Area	700 ha (1,700 acres)
Notification	1988
Location map	Magic Map

Abberton Reservoir
Abberton Reservoir Show map of England Abberton Reservoir Show map of Essex
Coordinates	51°49.2′N 00°51.6′E / 51.8200°N 0.8600°E / 51.8200; 0.8600
Lake type	Reservoir
Primary inflows	Pumped from River Stour and River Great Ouse
Managing agency	Essex and Suffolk Water
First flooded	1939
Surface area	700 ha (1,700 acres)
Max. depth	17 m (56 ft)
Water volume	41,000 megalitres (9.0×109 imp gal)
Ramsar Wetland
Designated	24 July 1981
Reference no.	220[1]

Abberton Reservoir is a pumped storage freshwater reservoir in eastern England near the Essex coast, with an area of 700 hectares (1,700 acres). Most of its water is pumped from the River Stour. It is the largest body of freshwater in Essex.

Constructed between 1935 and 1939, Abberton Reservoir is owned and managed by Essex and Suffolk Water, part of Northumbrian Water Group, and lies 6 km (3.7 mi) south-west of Colchester near the village of Layer de la Haye. In World War II, the reservoir was mined to deter invading seaplanes, and it was used by the RAF's No. 617 Squadron ("The Dam Busters") for practice runs for the bombing of the German dams in the Ruhr. A project to increase the capacity of Abberton Reservoir to 41,000 megalitres (9.0×10⁹ imp gal) by raising its bank height was completed in 2013, along with a new link to transfer water from Norfolk's River Ouse to the Stour.

The reservoir is important for its breeding cormorants, wintering and moulting waterfowl, and migrating birds. It is an internationally important wetland, designated as a Ramsar site, Site of Special Scientific Interest and Special Protection Area, and is listed in A Nature Conservation Review. A small part of the site is managed by the Essex Wildlife Trust.