This standard provides comprehensive guidelines for the planning and design of stormwater management systems in urban and developing areas. It covers methods for runoff estimation, design criteria for conveyance systems like pipes and channels, and introduces sustainable practices such as storage facilities and groundwater recharge structures. The code promotes a holistic approach to manage stormwater, mitigating flooding and improving water quality.
Offers comprehensive guidelines for the planning, design, construction, and maintenance of stormwater management systems in urban and rural areas.
Quick Reference Values
Minimum self-cleansing velocity in drains0.75 m/s
Typical Runoff Coefficient for Asphalt Pavement0.70 - 0.95
Typical Runoff Coefficient for Lawns (sandy soil, flat)0.05 - 0.10
Design return period for residential areas2 to 10 years
Design return period for commercial areas10 to 25 years
Manning's 'n' for Concrete Pipe0.011 - 0.015
Key Formulas
Q = C*i*A / 360 — Rational Method for peak runoff (Q in m³/s, i in mm/hr, A in ha)
V = (1/n) * R^(2/3) * S^(1/2) — Manning's formula for flow velocity
Practical Notes
The Rational Method (Clause 6.2) is primarily intended for small, simple catchment areas, typically less than 50 hectares. For larger or more complex catchments, hydrological modeling is recommended.
Rainfall Intensity-Duration-Frequency (IDF) data is a critical input for design. This data must be sourced from the local authority or the India Meteorological Department (IMD) for the specific project location.
This code encourages Low Impact Development (LID) and Best Management Practices (BMPs), moving beyond conventional piped drainage to include sustainable options like bioretention cells, swales, and permeable pavements.