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Answer on the book: EL. 36.90 m
An overflow masonry dam is to be constructed across a stream. The stream is estimated to have a maximum flood discharge of 850 m³/s when the elevation of the water sur- face is 345 m at the dam site. Six sluice gates each 2.5 m high and 2 m wide are to be constructed in the dam with their sills at elevation 342 m. The main overflow weir for which C 1.45 will be 60 m long with a crest elevation at 360 m. An auxillary weir 180 m long with a crest elevation at 361 m will operate during floods. For this weir C = 1.88. With all the sluice gates open, what will be the surface eleva- tion upstream of the dam when the discharge is 850 m³/s? =