GUIDELINES FOR THE ASSESSMENT AND LANNING OF ESTUARINE BARRAGES

In 1995 The Department of the Environment (DoE) commissioned HR Wallingford (HR) to learn from experience the essential elements of barrage design and consolidate the knowledge into guidelines for future application. The target audience is local authorities, the Environment Agency, development corporations and others who may wish to promote a barrage scheme, and consulting and contracting engineers who will be responsible for the design and construction.

The objective of the Environment Agency contract was "to review available experience on the design, operation and environmental impact of estuarine barrages in order to provide best practice design and operational engineering solutions to overcome or mitigate problems and enhance, where possible, the aquatic and riparian environment".

The paper describes the guidelines, highlighting the key issues form both engineering and environmental perspectives. The guidelines recommend that future barrage schemes should closely embrace the principles of sustainable development, thus ensuring that economic investment and environmental improvement go hand in hand.

The issues covered by the guidelines are: fisheries and conservation, water quality, hydrodynamics, morphology, flood defence, groundwater, navigation, waves, and structural design. Throughout the research, gaps in knowledge and technology were identified and a list of research priorities is given.