Rain Water Harvesting Model of RAJUVAS
Necessity:– Bikaner has an annual rainfall of around 250 mm which falls short of requirements.
The main campus of RAJUVAS is spread over 63000 Sqm. of area. The annual rain water availability in the campus is expected to be around 95.00 lac liters. RAJUVAS was thinking of utilizing rainfall to enhance its green cover. Efforts were initiated very humbly to divert flowing water on its roads to green beds by the side of roads. After establishment of the University, plan was prepared to harvest rain water from the roofs of buildings, roads, water coming in the campus from outside and even rain water collecting around its boundaries.
Layout of rain water harvesting system:
Type 1: Harvesting rain water from buildings:– To collect rain water 5 RCC underground water tanks with total capacity of 9.5 lac liters have been constructed at different locations in the RAJUVAS campus. Out of these, 3 tanks are of 2.5 lac liters capacity each and 2 tanks with 1.0 lac liters each capacity, totaling to 9.5 lac liters. Surface and roof top rain water is collected in these tanks through pipe and chamber system. Collected water, after filtration, is stored in these tanks and over flow/surplus water is carried to the existing open dry well located within the campus and in two newly constructed soakage wells. It is expected that around 68.00 lac liters of rain water per annum shall be there for underground recharging. Simultaneously, RAJUVAS shall be able to utilize around 30 lac liters of water for drinking and other purposes. Complete system, including RCC underground tanks, chambers and pipe line system, filters and soakage wells have been constructed. The system is ready for collection of surface rain water and roof top rain water from existing buildings. The system is constructed is such a way that roof top water from any other building can also be carried to the main system. At present 5 building are connected to the main system in the first phase. Remaining buildings of the campus will be connected in second phase very shortly. The schematic diagram showing complete rain water harvesting system of RAJUVAS campus is enclosed for kind perusal.
Type 2: Harvesting of road surface rain water:– For this purpose, Toe walls along the sides of roads were built providing around a meter space between road and toe wall. This space was covered by cement blocks fixed on sand. The road as well as blocks provided ample slope to allow water to collect along the toe wall. Since, cement blocks have been fixed over sand, space between blocks (1-2 mm) allowed water to percolate into sand. Toe wail v/as punctured at appropriate places and GI pipes fitted in the hole across the toe wall. Excess water along toe walls was allowed through these pipes to the greenery bed providing sufficient water to plants and excess to be percolated in to the earth. The schematic diagram showing this type of water harvesting is enclosed for kind perusal.
Type 3: Harvesting of rain water accumulated at road junction out side boundary wall of RAJUVAS:– The boundary on the corner of hostel premises at Chaudhary Bhimsen Circle used to have around half a meter deep accumulation of rain water. This accumulated water used to disrupt the traffic at this busy square and leading to damage to NH 11. RAJUVAS thought it proper to harvest this rain water into our own land across the boundary wall. At three places, Hume pipes of 6” diameter were placed across the wall. Land near the boundary was dressed in a way that its level remains more than 1 feet lower than the road side level. This allowed water to flow into our campus and absorbed by soil. Now we have planned to develop a green belt at this point so that plants get many times more water. The schematic diagram showing this type of water harvesting is enclosed for kind perusal.