About the Detention Basin Sizing Calculator Online Free Tool

The Detention Basin Sizing Calculator Online Free Tool estimates required storage from peak inflow, controlled outflow, and critical storm duration using a simple volume difference method.

How to Use the Detention Basin Sizing Calculator Online

1. Enter peak inflow and controlled outflow in m^3/s.
2. Enter the critical duration in hours.
3. Run the calculation to estimate detention volume.
4. Use hydrologic routing for final basin sizing and outlet design.

Choosing Options Correctly

Inflow and outflow:
Inflow must be greater than controlled outflow for detention storage to be required.

Critical duration:
Use the duration that governs storage for the catchment and outlet condition.

Common Use Cases

• Estimate preliminary stormwater detention storage.
• Compare storage sensitivity to outflow limits.
• Screen basin volume before detailed hydrograph routing.

Quick FAQ

What does this size?
It estimates detention storage from simplified inflow, outflow, and duration assumptions.

Does it replace hydrologic modeling?
No. Real basin design needs rainfall data, hydrographs, routing, outlet control, freeboard, and local criteria.

Why does allowable outflow matter?
Lower allowable discharge usually requires more storage volume.

What else should be checked?
Check emergency overflow, sediment, maintenance access, side slopes, infiltration, and regulatory requirements.