| Cray Reservoir |
Article Index for Cray |
Website Links For Cray |
Information AboutCray Reservoir |
| CATEGORIES ABOUT CRAY RESERVOIR | |
| lakes of wales | |
| reservoirs in wales | |
| geography of swansea | |
|
The location of the reservoir was chosen so that it was upstream of the heaviliy industrialised parts of the Tawe valley and in an area of high rainfall with as large an upstream catchment as possible. This meant that the ideal location was just to the north of the Carboniferous Coal belt on the Old Red Sandstone at the edge of Brecon Beacons National Park. The 28 Metre high dam is at the lower end of a wide glaciated valley and is estimated to impound some 4.5 million tonnes of water. Upstream of Cray reservoir the land is largely upland moors or unimproved grassland with large areas now given over to plantings of Conifer s. The impounded water quality is therefore good and the water requires only minimal treatment before entering the water supply system. The treatment of screening, disinfection and lime dosing is carried out immediately below the dam at Nant yr Wydd Despite the generally excellent quality of the water, there have been occasional episodes of impaired quality mostly concerend with forestry planting and the release of diffcult to treat turbidity into the resvoir. On occasions when such raw water quality impairment has overwhelmed the treatment facilities, some Bacterilogical deterioration has been experienced in the downstream water supply system such as in 1981 . {Link without Title} SOURCES Water Supply and Forestry, a conflict of Interests - Cray Reservoir - a case study - C Stretton |
|
|