Kishau Dam Planning Division, Yamuna Bhawan, Dehra Dun.
A number of low drop structures, which have Froude number in the range 2.5 to 45 are constructed in this country. They include barrages, weirs, canal drops, head regulators, etc. The type of hydraulic jump encountered and the flow conditions in the stilling basin pose a problem for Hydraulic Engineer for suitable design of energy dissipators for ensuring minimum erosion and scour in the stream bed downstream. Model studies conducted at V.P.I.R.I. have shown that stilling basin Type I of U.S.B.R. and S.A.F. stilling basin do not give encouraging results and in most of the cases the final recommendations varied very much from U.S.B.R. practice. The paper includes the analytical and experimental approach to the problem and lays down certain design criteria for use of design and research engineers, which may be used for the design of stilling basins below weirs, barrages, etc. It is expected that the adoption of the design would give satisfactory results in the field.
