Water Security Program
Waste & WASH Program
Jal Rakshak & Water Guardian Network
PJRB SPARC
RWH MAINTENANCE GUIDELINES
Rainwater Harvesting System Maintenance. Rainwater Harvesting Systems should receive regular pre-planned maintenance to ensure maximum efficiency and prevent unexpected breakdowns.
MAINTAINING EACH COMPONENT
DO’S AND DON’T’S
The Recharge Pit made is covered with an RCC slab. However, openings having square manhole covers are left on the RCC slab. One opening leads to the Desilting chamber, one to the filtration pit and a small opening has been left above the Borehole. Start the cleaning of the RWH system with the structure located near the beginning of your storm water drainage system. You must clean in such a way that the last structure to be cleaned is the one that is at the final exit point of the drainage system. This is to ensure that any silt that flows accidentally through the storm water drainage system during the cleaning process does not again settle into the freshly cleaned structures.
STEP 1 – Provide proper cleaning gear to your Cleaning staff. This includes – safety helmet, rubber boots/gum boots, gloves & mask.
STEP 2 – Ensure that the tools are available. The basic tools required are:
- 1 iron bucket
- Rope
- A spade
- A 4 ft X 4ft sieve made with fine iron mesh and wood
- Atleast 200 litres of water per structure
- A hose pipe and a pump
- Atleast 2 cleaning staff
STEP 3 – Open all the manhole covers. Unscrew the MS Steel plates under them if any and keep them aside.
STEP 4 – Leave the manholes open for atleast 1 hour before the cleaning team enters the pit. This will allow any harmful gases that may have accumulated inside the pit to escape. This is essential to ensure the safety of the cleaning team.
STEP 5 – First take out the silt/debris from the Desilting Chamber
STEP 6 – Then clean the Filtration Chamber and take out filter media upto 3” to 4” from top of the Filtration Chamber.
STEP 7 – Wash the filter media with high pressure stream of water (like from a hosepipe). The washing must ensure that the silt sticking to the filter media is removed completely. A large Wire mesh (like a large sieve) may be used for the purpose. Make sure that the silt heavy water does not flow back into your RWH structure. Also clean the structures at the beginning of the drainage system first and those at the final exit point last.
STEP 8 – Place the filter media back in clean layers in the same order as it was when taken out taking care that the slotted portion of the borewell is completely covered. The top layer is the most critical. If its quantity gets reduced due to losses in the cleaning process, then replace it with fresh pea gravel.
STEP 9 – Clean the walls of the pit to remove any fungal growth or sticky debris that may contaminate water
STEP 10– Clean the Recharge Well when the filter media is taken out for washing. With the same hose pipe a high pressure stream of water may be used to open any closed slots. Also a high pressure stream of water may be directed towards the inside of the recharge wells so that the blockages from inside are also removed.