DrainageCalculators

Road & Infrastructure Drainage

Roadway drainage, culvert sizing, channel design, and infrastructure-scale systems.

6 calculators recommended for this problem

Recommended Calculators

These tools are most useful for solving "road & infrastructure drainage" problems.

Manning's Equation for Pipe Flow Calculator

Calculate pipe flow discharge, velocity, and hydraulic properties using Manning's equation. Supports full and partial flow in circular pipes with imperial and metric units. Free online tool for drainage engineers.

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Manning's Channel Calculator

Calculate open channel flow using Manning's equation. Supports rectangular, trapezoidal, triangular, and parabolic channel shapes. Free professional-grade hydraulic engineering calculator.

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Culvert Outlet Control Calculator

Calculate outlet control hydraulics for culverts including headwater depth, outlet velocity, critical depth, normal depth, and head loss breakdown. Uses FHWA HDS-5 methodology for circular and box culverts.

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Inlet Interception Calculator

Calculate inlet interception efficiency for roadway drainage using HEC-22 methodology. Analyze grate, curb-opening, and combination inlets. Determine captured and bypass flows. Free professional-grade drainage calculator.

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Gutter Flow Calculator

Calculate gutter flow capacity using Manning's equation. Analyze K-style, half-round, and box gutters. Determine flow velocity, hydraulic radius, and Froude number. Free professional-grade roof drainage calculator.

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Outlet Protection Calculator

Design riprap aprons and outlet protection structures for culverts using FHWA HEC-14 methodology. Calculate D50 stone size, blanket thickness, and apron dimensions.

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