Designing Filters For an RWH System : Inexpensive methods sought!
Submitted by iwp on June 23, 2009 - 21:31
We are interested in installing a RWH system in our housing society building. The details of the building:
Total terrace /catchment area = 4000 sq ft
We have one two underground tanks of 15000 lt each and a over head tank of 10000 lt
We are very tight on budget so can’t effort to hire a consultant, We have already done some research and figured out how to divert the terrace water to the underground tank etc., we just need suggestion on the filter( detailed design and installation method) that needs to be installed before the water falls in to the underground tank.
We are not looking for an expensive filter as this water will not be used for drinking. Any other precautions that need to be heeded may also be indicated.
Praveen
Comments
1.
Dear Mr. Praveen
Congratulations.
You can simply use small constructed pit filled with clean river sand. Size of feet may be 0.5X0.5 M. Depth 0.5 M. Free board 0.3 M. This will filtered out the rain water. Inlet at top and outlet at the bottom.
If it is chocked remove the sand and refill with fresh sand
Prof. R. V. Saraf
Director
Viraj Envirozing India Pvt. Ltd.
21 Radhakrishna, Near SBI
Paud Road, Pune 411 038
Tele/Fax: (020) 25433445
Web: http://www.virajenvirozing.com
E Mail: watersgs@vsnl.net
info@virajenvirozing.com
2.
Dear Praveen,
If only roof top water needs to be harnessed, it is simple to have a de-silting chamber before storing into the UG tank. The only precaution needed is that the initial runoff is not to be tapped as this would make the catchment clean. Subsequent runoff can be diverted to the UG tank by de-silting mechanism and no special filters are required. As regards to precaution, please ensure that no contaminated water is diverted to the UG tank.
Thanks,
D. Chakraborty
Scientist
Central Ground Water Authority (CGWA)
New Delhi
3.
Dear Sir,
Filters unless designed carefully (I will not use the word scientifically) prove to be counter productive. My simple suggestions are:
1. Use a first flush arrangement.
2. In case one insists on a filter, construct a masonry tank (size:2 ftX2 ftX3 ft) above the ground, fill up to one fourth its volume with medium sized gravel.
3. Keep the roof as clean as possible by sweeping it as often as possible at least during monsoon months.
Sekhar Raghavan, Rain Centre, Chennai
Post new comment