Generalized Flow Rating Equations at Prototype Gated Spillways

Gated spillways are used to control flow in canals, rivers, and estuaries. Despite their widespread use, available flow ratings at these gated structures are largely derived from reduced-scale laboratory models. In this paper, generalized flow rating equations are developed based on field flow measurements collected mostly with an Acoustic Doppler Current Profiler at about 90 prototype gated spillways in South Florida. The proposed ratings, developed using dimensional analysis, agree well with field measurements. A single generalized equation that is applicable to all flow conditions was also developed. This generalized equation addresses the limitation of continuity of the calculations as flow transitions from one condition to another.