Plans to construct a barrage across the entrance to Cardiff Bay on the South Wales coast were evolved by the Welsh Office in 1986 in parallel with proposals to establish an Urban Development Corporation to redevelop 1080 hectares of derelict land in South Cardiff. The proposed barrage which is 1.4 kilometres in length will cut the bay off from the adjacent Severn Estuary.
The project was first promoted in 1987 necessitating a Parliamentary Bill to permit its construction in tidal waters. Since the first private Bill was introduced in November 1987 there has been concerted opposition to the proposals, in the main due to the inundation of a winter feeding ground for wading birds (protected SSSI), concerns over water quality and flooding, and fears of a catastrophic rise in groundwater level as a result of the impoundment and the impact of such a rise on the infrastructure of the city.
This paper reviews the work undertaken to assess the impact of the impoundment on the existing groundwater regime as presented to the various Parliamentary Committees and to the public.