Excel Spreadsheet Templates for Manning Equation Calculations with Partially Full Pipe Flow

If you have to make Manning equation/uniform open channel flow calculations for a partially full pipe flow these Excel spreadsheet templates may help. The Excel formulas use the equations that relate the pipe radius, depth of flow, and circular segment height, area, and arc length to the cross-sectional area of flow, wetted perimeter and hydraulic radius. This article uses a model with Manning roughness coefficient varying with the ratio of depth of flow to diameter.