Water Quality
The Estuary is polluted with silt, sewage, industrial chemicals (especially Cadmium) and radionuclides from the nuclear power stations.
With a barrage in place there would have to be a "Zero Emissions" policy throughout the Severn catchment area, in order to prevent unacceptable buildup of pollutants, since the tidal "washing" effect will be greatly reduced.
Zero emission is practicable but costly. However, the advantage is that by pioneering the ZE technology and processes, we can lead the world in this technique, and export knowledge and technologies.
Siltation is a real threat to any brrage, and would have to be actively prevented and managed.
page revision: 3, last edited: 09 Oct 2007 15:20