ABSTRACT
Sluice gates are provided at the end of drainage channels to alleviate drainage congestion on coastal and deltaic areas. Tides normally enter freely and propagate upstream. In rainy season when the channel is fed at its landward end with run-off from the drainage area, there is an interplay of fresh and tidal water. During the dry months of the year the tidal flow dominates. Significant run-off from drainage is generated only for a few days in a year. The design of drainage channels should thus be based on tidal flow modified to accommodate the upland discharge during rains. The design of a drainage channel with a sluice gate at the outfall is presented. A drainage channel with a sluice gate at the outfall where the tides are to play has to bear some relationship with the dimension of the sluice. Fish farming in coastal areas also designated as brackish water aquaculture depends mostly getting its water supply from tidal creeks.
