Dos and Don't for RWH

DO'S of Rainwater Harvesting/Recharging:

• The roof should be kept clean before rains.
• Suitable filtration methods have to be adopted to filter rainwater.
• Filters have to be regularly maintained /cleaned.
• All plumbing works have to be done properly using appropriate materials.
• Suitable clamps for all pipes and gutters have to be fixed at a maximum interval of 1m.
• Storage devices like sumps/tanks/vessels need to be cleaned before storing filtered rainwater.
• Rainwater storage devices must have proper manhole covers, which should not permit sunlight into the tank.
• Paint the surfaces (inside and outside) of masonry tank/sump with lime every year.
• Provide good quality, leak proof taps that are convenient for use.
• Check the quality of stored rainwater for bacterial contamination every year if used for drinking.
• The first flow of rainwater that contains contaminants from the roof must be allowed to drain out (first flush).
• Sand bed filters need to be installed with properly cleaned riverbed sand and aggregates. The sand, aggregates and plastic mesh of the filter have to be washed, sun dried and refilled every month.
• Rainwater is pure and can be used for drinking, cooking and all other purposes, as it is free from fluoride, arsenic, bacteria, etc., However, contaminants may get added over the collection surface like roof / open space.
• Wherever possible ground water recharge methods have to be adopted for rooftop rainwater or overflow of rainwater from tanks/sumps.
• The sand and aggregates used in infiltration gallery should be cleaned, washed and sun dried before placing them in the infiltration gallery.
• The open wells have to be desilted and cleaned before being used for ground water recharge.
• Pump-in test has to be carried out for bore wells before adopting direct injection of rainwater for ground water recharge.

DONT'S of Rainwater Harvesting/Recharging:

• Rooftop rainwater or surface runoff should not be directly consumed without filtration and proper disinfection.
• The tanks/sumps used for storing rainwater should not have any opening that permits sunlight inside. Entry of sunlight into the sump/tank encourages bacterial and algal growth.
• Collection of water by vessels/buckets from tanks/sumps through manholes has to be avoided and taps/pumps/hand pumps must be used.
• Rainwater from the roof or open spaces must not be directly allowed to flow into the bore well casing pipe. Preferably an infiltration gallery method must be adopted for ground water recharge.