IS 16016:2012 is the Indian Standard (BIS) for installation of rainwater harvesting systems in buildings. This code provides guidelines for the planning, design, construction, installation, and maintenance of rainwater harvesting systems in buildings. It details system components such as catchment areas, conveyance systems, filters, and storage tanks to promote water conservation and sustainable water management.
Provides guidelines for the installation of rainwater harvesting systems specifically within building premises.
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| First Flush Diversion Guideline | Divert first 10-20 minutes of rain, or a volume equivalent to 0.5-1.0 mm of rainfall over the catchment area. | Divert a volume equivalent to 1-2 mm of rainfall. Some jurisdictions specify a fixed volume per area (e.g., 40 L per 100 m²). | CSA B805-18 / General Best Practice |
| Mains Water Top-up Backflow Prevention | An air gap shall be maintained between the potable water inlet and the maximum water level in the tank. | A verifiable air gap (e.g., Type AA or AB as per UK regulations) must be used to prevent backflow into the public water main. | BS 8515:2009+A1:2013 |
| Pipe Identification | Pipes should be marked 'NON-POTABLE RAINWATER'. No specific color is mandated. | Pipes must be colored purple (lilac) or have purple identification tape, and be labeled 'RAINWATER' or 'NON-POTABLE WATER'. | AS/NZS 3500.3:2021 / ICC 805-2018 |
| Pre-storage Filtration | Prescribes physical filters like sand-gravel beds with specific layer depths (e.g., 20-30 cm fine sand, 10 cm gravel). | Specifies performance-based filtration, e.g., a filter with a mesh size of 300-500 microns before the tank. | BS 8515:2009+A1:2013 |
| Tank Sizing Methodology | Based on a formula for total potential harvest: Area x Rainfall x Runoff Coefficient. | Often uses a detailed water-balance analysis, comparing monthly rainfall supply against monthly water demand to optimize size. | CSA B805-18/ICC 805-2018 |
| Tank Overflow Sizing | The overflow pipe should be of the same diameter as the inlet pipe. | Overflow must accommodate the maximum possible inflow from a design storm and be at least the same nominal size as the inlet. | AS/NZS 3500.3:2021 |