Advanced stormwater tools for peak flow, Tc, and pond sizing. Calculate rain gardens, bioretention, and permeable paving for sustainable urban drainage systems.
| ARI | Intensity (mm/hr) | Peak Q (L/s) |
|---|
| Segment | Length (m) | Slope (%) | Velocity (m/s) | Time (min) |
|---|
| Pollutant | Typical Removal % |
|---|---|
| Total Suspended Solids (TSS) | 85% |
| Total Phosphorus (TP) | 65% |
| Total Nitrogen (TN) | 45% |
| Heavy Metals (Zn, Cu, Pb) | 80% |
| Bacteria / Pathogens | 70% |
CalcType: Professional Stormwater Hydrology & Blue Infrastructure Solutions — This advanced hydrological suite is engineered to facilitate precise runoff management and climate-resilient site design for landscape architects, civil engineers, and urban planners. Our platform integrates the industry-standard Rational Method for peak discharge estimation, alongside detailed Time of Concentration (Tc) calculations utilizing Manning’s kinematic formulas for sheet flow and concentrated flow paths. By offering specialized modules for Nature-based Solutions (NbS)—including rain garden sizing, bioretention cell capacity, and permeable paving runoff reduction—CalcType empowers designers to meet municipal stormwater quality and quantity requirements through integrated green infrastructure. Furthermore, the tool includes engineering-grade verification for detention pond attenuation and outlet structure hydraulics, specifically for sizing orifices and weirs to prevent downstream flooding and erosion. Whether you are managing the first flush of a design storm or engineering complex attenuation systems for high-density urban developments, our calculators provide the technical rigor required for sustainable, data-backed water management. Technical Disclaimer: The hydrological data and sizing results provided by this calculator are intended for preliminary estimation and conceptual design purposes only; all final drainage plans, structural detention systems, and peak flow calculations must be verified by a licensed professional engineer (PE) or landscape architect (PLA) following a site-specific geotechnical and hydraulic analysis. Actual runoff coefficients, soil infiltration rates, and rainfall intensities may vary significantly from modeled data; therefore, CalcType assumes no liability for site flooding, structural failures, regulatory non-compliance, or financial losses resulting from the use of these tools.