a contracted horizontal weir placed within a concrete lined rectangular channel. A diversion channel branches off of the given rectangular channel 1,000 ft upstream of the weir. In order to provide the necessary discharge to the diversion channel, the flow depth at 1,000 ft upstream of the weir needs to be 3' when the discharge (Q) is 500 cfs. Determine the height that the adjustable head gate should be raised above the bottom of the weir (z