摘要 |
A barrier for diverting fish from a water flow channel such as an intake (12) consists of a dyke (10) enclosing the water intake, and extending at least the entire depth of the body of water. There are pipes (20) extending between opposite sides of the dyke (10), of diameter at least 800 mm (31 inches). The inlet end of each pipe (20) communicates with the body of water through one or more inlet ducts (26) of width no more than 600 mm (24 inches), this being a duct size to which the fish from the body of water have an aversion. Each inlet duct (26) may also be aligned at least 45.degree. below the longitudinal axis of the pipe (20). The confined space, the resulting darkness, and the change in water flow direction, all have the effect of discouraging fish from entering the ducts. The number of pipes (20) should be sufficiently large that the intake velocity will be less than 150 mm/s (0.5 ft/s), to minimise entrainment or impingement of fish. (Figure 1)
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