Outer Trial Bank
|Outer Trial Bank|
|Location||The Wash, East Anglia, England|
|Area||4.265 hectares (10.54 acres)|
In 1972, the Government undertook a study to assess the feasibility of building a tidal barrage across half of the Wash. The idea was to capture the freshwater from the River Witham, River Welland, River Nene and Great Ouse to build a freshwater reservoir. The study also intended to establish potential improvements to the navigation of sea locks, provide recreational facilities and develop an area of land for a power station.
Construction of the banks
As part of the test, the approval to build an artificial island 2 miles (3.2 km) off the Lincolnshire coast was given in November 1974. Building work began in February 1975. The bank (known locally as "the doughnut" due to its biconcave shape) was constructed of a sand fill protected by limestone riprap. Measuring 250 metres (820 ft) in diameter, the island contained a small reservoir measuring 1 hectare (2.5 acres) in the centre.
The study, which was published in 1976 as "The Wash storage scheme", found that the trial alone proved financially unfeasible (costing £3 million), and that the freshwater was too close to the tidal estuary to ensure low salinity and minimal silt levels. The trial was soon abandoned and the plans for the scheme shelved.
- Richards, Matt (8 October 2008). "Investigation of Wash Island". BBC Look North. BBC. Retrieved 1 March 2010.
- "The Past". The Wash Project. The Wash Estuary Strategy Group. Archived from the original on 11 October 2006. Retrieved 1 March 2010.
- "Wash Water storage scheme" (PDF). News and Views. British National Committee on Large Dams (16): 15–16. 1975. Retrieved 2 March 2010.
- "Abandoned: What's in the Wash?". BBC Lincolnshire. BBC. 15 October 2008. Retrieved 1 March 2010.
- "The Wash storage scheme: report on the feasibility study". Central Water Planning Unit. The National Archives. 1976. Retrieved 1 March 2010.