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Title: Llyn Tegid dual pumping scheme : preliminary study report
Author: National Rivers Authority Welsh Region
Document Type: Monograph
This report was prepared by Binnie Black an Veatch in response to a request from the National Rivers Authority (NRA), Welsh Region to study the feasibility of pumping water from Llyn Tcgid to Llyn Celyn and to the river Dee. The NRA operates the River Dee Regulation Scheme and is a leading member of the River Dee Consultative Committee. Other members of the committee represent the main water abstractors, namely: North West Water; Dwr Cymru Welsh Water; Wrexham Water Co; Chester Water Co, and British Waterways Board. The three major reservoirs of Alwen, Brenig and Celyn, constructed as new storage, are relatively large for their catchment areas with the result that filling is not assured during years of less than average rainfall. Llyn Tcgid, however, was developed by raising the outlet of a natural lake and drains a relatively large catchment. In every year since its raising, Llyn Tegid has received ample inflow, using its variable storage capacity to reduce flood peaks and spilling surplus flows into the River Dee. Low rainfall during the summer and autumn of 1995 has left the existing reservoirs significantly depleted. It is feared that should another dry year ensue, there will be insufficient water in storage to maintain the required flow in the River Dee. In December 1995 NRA commissioned preliminary study of measures to alleviate possible shortages in 1996 and beyond.
Publisher: National Rivers Authority
Publication Date: 1996
Publication Place: Bangor
Subject Keywords: Water reservoirsWater resourcesWater supplyWater storagePumpsDroughtWater levelsRivers
Geographic Keywords: WalesGwyneddUpper Dee catchmentDee (Wales)
Extent: 26; + appendices
Total file downloads: 55

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