CHAPTERS
Towards Developing Guidelines for Assessment,
Design and Operation of Estuarine Barrages
T. Neville Burt . Ian C. Cruickshank . Mervyn A. Littlewood
5.1
Introduction
Many large-scale barrage schemes are under consideration both in Europe and worldwide. Some have been built, some are under construction and some are in their design
development stage. The authors have been involved in feasibility studies for five of
them from London's Thames Barrier in the early 1970S to the Cardiff Barrage in more
recent years. Whether we call these structures barriers, barrages or, in some cases, weirs,
they are all, for various reasons, designed to modify or totally prevent the progression
of the tide up an estuary or inlet. This change to the natural tidal progression has wide
ranging implications on the estuary regime. Therefore setting the environmental policy
for barrages epitomises the problems associated with any large-scale construction in
tidal estuaries. At present there is little in the way of design guidance to help the developer or the regulators. It seemed an appropriate time to review what had been learnt in
order to provide environmental policy guidelines for future schemes and identify research priorities to achieve sustainable development.
A research project was set up at HR Wallingford to achieve this, funded by the UK
Department of the Environment and the Environment Agency. Information has been
gathered from as many barrage projects as possible worldwide and is currently being
assessed by a number of specialists. The end product will be published guidelines on
the assessment, design and operation of estuarine barrages covering a wide range of
issues under the broad headings:
• Barrage concepts, planning and legislation
• Fisheries
• Conservation
• Hydrodynamics
• Morphology
• Flooding
• Groundwater
• Water quality
• Navigation
• Waves
• Structural engineering concepts
• Water-related risk
Environmental science is still developing and we do not yet fully understand all of
the processes involved. With the advent of the Rio Summit and conservation directives
Towards Developing Guidelines for Assessment,
Design and Operation of Estuarine Barrages
T. Neville Burt . Ian C. Cruickshank . Mervyn A. Littlewood
5.1
Introduction
Many large-scale barrage schemes are under consideration both in Europe and worldwide. Some have been built, some are under construction and some are in their design
development stage. The authors have been involved in feasibility studies for five of
them from London's Thames Barrier in the early 1970S to the Cardiff Barrage in more
recent years. Whether we call these structures barriers, barrages or, in some cases, weirs,
they are all, for various reasons, designed to modify or totally prevent the progression
of the tide up an estuary or inlet. This change to the natural tidal progression has wide
ranging implications on the estuary regime. Therefore setting the environmental policy
for barrages epitomises the problems associated with any large-scale construction in
tidal estuaries. At present there is little in the way of design guidance to help the developer or the regulators. It seemed an appropriate time to review what had been learnt in
order to provide environmental policy guidelines for future schemes and identify research priorities to achieve sustainable development.
A research project was set up at HR Wallingford to achieve this, funded by the UK
Department of the Environment and the Environment Agency. Information has been
gathered from as many barrage projects as possible worldwide and is currently being
assessed by a number of specialists. The end product will be published guidelines on
the assessment, design and operation of estuarine barrages covering a wide range of
issues under the broad headings:
• Barrage concepts, planning and legislation
• Fisheries
• Conservation
• Hydrodynamics
• Morphology
• Flooding
• Groundwater
• Water quality
• Navigation
• Waves
• Structural engineering concepts
• Water-related risk
Environmental science is still developing and we do not yet fully understand all of
the processes involved. With the advent of the Rio Summit and conservation directives