Drain Tile Size Calculator
Calculate the required drain tile pipe diameter from drainage area, drainage coefficient, and pipe slope using Manning's equation for agricultural tile design.
Free Drainage Calculators
6 toolsTile drain, waterway, and drainage design tools. Browse our free drainage tools below — no sign-up required.
Drainage Coefficient Calculator
Calculate the drainage coefficient (DC) in inches per day needed to remove excess water from agricultural fields. Size tile drains and surface systems.
Grassed Waterway Design Calculator
Calculate the design flow for a grassed waterway using the Rational Method from drainage area, rainfall intensity, and runoff coefficient.
Retention Pond Sizing Calculator
Calculate the required retention pond volume from storm depth, drainage area, and runoff coefficient. Size stormwater retention for agricultural and rural sites.
Terrace Spacing Calculator
Calculate agricultural terrace spacing from land slope, soil type, crop type, and management practice. Reduce erosion with properly spaced terraces.
Tile Drain Spacing Calculator
Calculate tile drain spacing using the Hooghoudt equation from soil hydraulic conductivity, drain depth, and drainage coefficient for farm fields.