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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.

Civil

Earthwork Excavation Calculator

Estimate excavation volume, total cost, and number of truck loads needed for any construction dig. Perfect for contractors, estimators, and project managers budgeting foundation, trench, or bulk earthworks.

Excavation Length (m)

Excavation Width (m)

Excavation Depth (m)

Cost per Cubic Meter ($)

Fill in the required fields to see your result.

Key differences

	Storm Water Drainage Calculator	Earthwork Excavation Calculator
Category	Civil	Civil
Inputs required	5	4
Result	Required Pipe Diameter (mm)	Total Excavation Cost ($)
What it does	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.	Estimate excavation volume, total cost, and number of truck loads needed for any construction dig. Perfect for contractors, estimators, and project managers budgeting foundation, trench, or bulk earthworks.