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Water Supply Pipe Sizing Calculator

Determine the minimum pipe diameter needed to deliver a required flow rate under specified pressure and elevation conditions. Used by hydraulic engineers designing water mains, irrigation systems, and building reticulation.

Required Flow Rate (L/s)

Pipe Length (m)

Elevation Difference (m)

Minimum Pressure Required (kPa)

Pipe Material

Fill in the required fields to see your result.

Civil

Storm Water Drainage Calculator

Estimate peak stormwater runoff and determine the minimum pipe diameter needed to handle it. Used by civil engineers and drainage designers when sizing pipes for subdivisions, roads, or urban catchments.

Catchment Area (hectares)

Design Rainfall Intensity (mm/hr)

Runoff Coefficient

Pipe Slope (%)

Manning's Roughness Coefficient

Fill in the required fields to see your result.

Key differences

	Water Supply Pipe Sizing Calculator	Storm Water Drainage Calculator
Category	Civil	Civil
Inputs required	5	5
Result	Required Pipe Diameter (mm)	Required Pipe Diameter (mm)
What it does	Determine the minimum pipe diameter needed to deliver a required flow rate under specified pressure and elevation conditions. Used by hydraulic engineers designing water mains, irrigation systems, and building reticulation.	Estimate peak stormwater runoff and determine the minimum pipe diameter needed to handle it. Used by civil engineers and drainage designers when sizing pipes for subdivisions, roads, or urban catchments.