www.BPODigest.com i-Vortal

We are in the process of extending this concept to many more villages in Karnataka.
regards

Here is a somewhat different water harvesting concept , not connected with rtwh.

City Ring water harvesting.
---------------------------
current status
-this is mainly applicable to the cities
-where there is acute water shortage, plus supply it is unreliable and
irregular, contaminated.
People are forced to buy water. In one case , i have read that per family
water expense is of the order of 1500 rs per month.
-water has to be piped from reservoirs/rivers from long distances
-water table has gone down dangerously
- in any case, water can no longer be treated as free commodity and some
reasonable charges will be borne by users.
- the water harvesting IN the city area is quite difficult . roads and pucca
surfaces make the water run off. The water is dirty. It can contain a lot of
dangerous organic and inorganic pollutants. Also

A concept:

- imagine a band of about 5 kms at a distance of 5 kms from the periphery of
the city
after considering expansion margins is to be defines.
-this ribbon will be having sparse population and only farm or fallow land.
Some villages and grampanchayats etc will be there.
-it is to be devided into about 5km x 5km squares
- each squarish area, should be contoured to find run offs and taalaabs.
Talaabs should be dug to
collect this run off as needed , as close to city perphery as possible.
- all the run off water from the ribbon will be collected in these multiple
ponds. Current depressions/tanks should be considered.
- from these ponds the water should be piped or transported to the city
periphery. At suitable charges.
- the grampanchayats should make the "works" self financing by proper pricing
in the long run.

So typically:
a city of about 10 km radius plus about 5 km expansion will have a ring band
of about 18km radius. i.e. 3.14 x 35 = about 110 kms = about 22 tanks areas

Each with a water collection of over 25 sq km , at 40 cm rainfall collection =
about 10 mn cu mtrs collection. 22 tanks = 220 mn cu mtr collection.

At 50 ltrs/day/person, for 10 lak persons, we need about 18 mn cu mtrs per
year.

These figures canl very a lot , but still they have great potential.

- employment generation away from city
- earning to grampanchayats

I have done these calculations many times over, with many mistakes. I hope
they are ok now. Pl see the attached file

This concept may be worth discussing.

regards
r m ranade

========
city ring water solution jan 2005

ltr/day/hd=50 dia city+10kms=30
days/yr=365 city area km sq=706.5
ltrs/head/ per yr=18250 ring outer dia=40
ltrs/cu mtr=1000 all area=1256
cu mtrs/per/yr=18.25 ring area sq km=549.5
population=1000000
need cu mtr per yr=18250000

usable rain mtrs=0.5
area needed sq mtr=36500000
sq mtrs / sq km=1000000
needed area km sq=36.5 549.5

========

Rajendra,
First of all it is good that you think about innovative ideas. That was the good news.
Here comes the bad news so brace yourself.
Have you factored in land costs? In my city Bangalore, land prices 30 kilometres away are in the range 4000 Rs a square metre. So land measuring 5 kilometres by 5 kilometres would be , hold on to your seats, Rs 10,000 crores.
Now work out the figures for your needed area.
What we need to do in cities is for each one of the buildings to harvest rainwater. Store some and recharge the others. The water that flows on roads and paved areas should pass through wetlands and be harvested in lakes and 'tanks' as they are called here in Bangalore.
Through this combination we can start to become self sufficient for our water requirements.
cheers
Vishwanath

Hello Vishwanath,

That is a perfect critic.

Presonally I really appreciate your efforts. I would also like to see you coming up with solutions for harvesting rainwater in rural areas so that they never have to worry about thier crops failing. If you can do that that will be a wonderful thing for India.

Ram,
I am working in rural areas , with a three or rather four pronged strategy.
1. For water for domestic consumption - we are designing and building rooftop rainwater harvesting structures. Even small tanks of 2500 litres capacity can harvest rainwater to the extant of 20,000 litres annually and provide much needed supplemental water for the families requirements
2. The same technique is used for collecting rainwater for domestic animals such as cows,buffaloes,goats and sheep.
3. Rooftop rainwater harvesting in school buildings provides water for children in the school.
4. For agricultural purpose, tanks are desilted and water collected, borewells/open wells recharged and farm ponds are built.
The progress is slow but steady.
With my experience I can say that We do not have a water crisis, we have a water management crisis.

Vishwanath,

I totally agree with you that we have a water management crisis. During summer we cry about lack of water and do nothing to capture water during rainy season. People like you must influence the government to implement village level water catchment technologies. Making village panchayats responsible to maintain these technologies must also be done.

Hi,
It was very interesting going through the various posts.

I have a site (30x40) in HSR layout and I am about to start building a house there. I plan to have a 6" borewell and also a Sump.

Please let me know the best method for RWH for my house.

Thanks in advance
Sathyan

the places like konkan we have huge rainfall but due to hilly terrain the water runs off to sea in no time. also we have rockey soil (basalt) which absorbs very little water. we have acute water shortage each year after february.

i suggest the we can have check dams in the innumarable 'nalla's (since we hardly have rivers and the ones that are there are heavily polluted). when i tried this idea in my plot which is away from my house i was discouraged since such open tank will be invitation to children to go there and swim and there could be deaths due to drawning. i cannot spend money to close such tank but i can definitely construct a small dam to retain water. another problem will be that the village belles will start washing the clothes there and make the entire water soapy solution.the third problem is of stray animals like dogs,cattle,sheep etc. who will make it a swimming tank.our people are not educated enough in public hygiene and they want everything free whether it belongs to them or not,no one is bothered about what my action will do for the next man. i was also told that in case of any death in the pond (or so called tank)i will be held responsible and jailed. then why should i go ahead and do it?.
in our area there are many abandoned stone queries which are sufficiently deep and rectangular. with proper planning and guidelines to workers we can get these queries to be in tank shape (usually they leave an outlet to let water run off. this should be avoided.) and these could be readymade water harvesting tanks but this land usually belongs to government. can somebody do it with the government? ---madhav bhide

If Sathyan has not finished his house here is a tip for him. Collect all the rainwater from the rooftop on one side of the house with 2 downpipes of 100 mm. Filter the water. Lead it into yur sump tank. Overflow lead it into a ring well of diameter 3 feet and depth about 20 feet. If you are not on the tank bed side of the layout this should work. Oherwise you will have so much flood water that this may not work for some time during the rains. Best of luck anyway.
Madhavs'is a slightly more complex issue. Madhav I would suggest that you need not listen to all and sundry. Here in our beautiful land EVERYBODY has at least one opinion and preferably two depending on their mood. The argumentative Indian for sure.
Go ahead build the ponds or the check dams but take the trouble to talk to people. Not jus once but many times. They are not as dumb as they are painted. In fact I have seen village women buy cello tape and seal their roof rainwater tanks to prevent mosquitoes from breeding. This after a reasoned dialogue with them over several visits.
Now the good news . In Karntaka we have rooftop rainwater harvesting going on in over a 1000 villages funded by the government. We also have approval for the desilitng and rehabilitation of over 36,000 tanks/ponds. The gram panchayats are in charge of both the schemes. Especially womens self help group are evincing keen interest.
Take a look at the article nk.pdf in the downloads section of www.rainwaterclub.org if you are interested.
regards
Vishwanath

Please let us know who is the authority to contact.. we want to implent for our residential purpose.. we wold like to know how to go about it. pl furnish the contact no and other details