Spillway Gates allow increased water storage capacity at new or existing reservoirs with little or no decrease in spillway capacity. In the case of legacy spillways recently determined to have inadequate flood flow capacity, the spillway invert may be lowered to provide the required flood flow capacity while gates are installed to provide increased storage capacity and increased reservoir yield. This avoids the usual compromise between adequate spillway capacity to accommodate floods, and desired water storage capacity. Adding capacity to existing reservoirs by installing Spillway Gates also eliminates the political and financial hurdles and delays which the construction of new reservoirs may entail. Installation of gates for spillway control allows cost effective increases in useful storage capacity on a short timetable.
