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Cowx, I. G. (1998). Fish passage facilities in the UK: issues and options for future development. Pages 220-235 in M. Jungwirth, S. Schmutz and S. Weiss, eds. Fish Migration and Fish Bypass Channels Symposium, Fishing News Books, Vienna (Austria).

Provision for the migration of fish has a long tradition in the UK. However, the mechanisms by which it has been achieved have varied greatly as has the degree of success in maintaining migratory pathways. Most attention has focused on upstream migration of salmonids past medium and large impoundments (weirs and reservoir dams). More recently, attention has focused on using alternative channels, such as canoe slaloms, to bypass weirs and barrages, and improving access to natural spawning beds past small man-made obstructions such as road culverts and badly designed or located low weirs which impede upstream movement. In recent years, in the face of declining European eel, Anguilla anguilla stocks and emphasis on improving fishing for other non-salmonid fishes, provision has been made for improving upstream migration of elvers and non-salmonids over difficult and insurmountable man-made obstructions. Legislation and provision for the design of fish passage facilities for migratory salmonids are under the direct control of the Environment Agency. They impose strict guidelines for designing passes and require that facilities at new barrages, particularly in estuaries, are adequately tested before they are given approval. With increasing pressure on improving river fisheries and the environment, there are many rivers now being considered for rehabilitation. This includes providing fish passage facilities at the many weirs built on rivers in the industrial past to providing renewed access to the headwater spawning and nursery areas. To date, little attention has been paid to the economics of such activities but this situation is changing rapidly and demands for cost benefit analysis are being imposed. An example is described where the decision to build fish passes on the many weirs impeding upstream migration was deferred on economic grounds. Finally, there are some controversial situations, where passage past natural barriers to previously inaccessible spawning and nursery grounds are discussed.