Roof Top Rain Water Harvesting for Water Storage at UVPCE, Ganpat University

Roof Top Rain Water Harvesting for Water Storage at UVPCE, Ganpat University

Dhaval M Patel*, Abhijitsinh Parmar**, Harpalsinh Raol***, Jitendra Jayswal*, Gajjar Harshil*

*ME(WRM),LDCE; **Asst. Prof., SVBIT, ***ME Transport, GEC Madasa

North Gujarat is water scarce region. The rainfall is irregular in nature. Ground water is major source of water and that's why ground water is declining day by day. It has resulted in the alarming depletion (3.57 m/yr) of water level & drastic deterioration in ground water quality. In Mehsana average rainfall is below normal rainfall (647.10 mm). One of the simple methods of solving the problems of water & draught in different parts of a water harvesting is the collection of rain water from the different areas like roof of building, open spaces surrounding the building, farm-areas, etc. and then storing it for a later use or diverting it to an existing well for recharging.

1. Fig 1 Google image of study area UVPCE

   Rain water harvesting is the accumulation/ deposition of rainwater for reuse before it reaches the aquifer.[1] Around third century BC, the farming

   communities in Baluchistan and kutch used rainwater harvesting for irrigation.[2] In Tamil nadu, rainwater harvesting was made compulsory. Rain

   water harvesting means collecting rain water from the top of roof and storage in the water tank. Generally two type of water tanks are utilised- under ground water tank and above ground water

   tank . When the first rainfall of the season occurs, the water accumulated on the roof top is contaminated with various toxic gases as well as the dust on the roof top. Hence this accumulated water is generally flushed off as it is not suitable for drinking purpose. The primary need of such system is that water accumulated on the roof top must flow down under gravity for the use and the storage tank must be well cleaned prior to the use.

   why we are providing roof top rain water harvesting in college building? because now a days there are no reliable sources of water in the college. So problem is created for primary use of water. In such circumstances rain water harvesting can prove to be appropriate measure to conserve water .This conserved water can be used for cooking, bathing, washing clothes, toilet flushing and various hygienic purpose and finally if the rainwater is treated well then can be utilised for drinking purpose also.

   Even after first flushing of accumulated roof top water, the water collected will consist of various impurities and hence will be unsuitable for the usage of the water. So the accumulated roof top water is allowed to pass through charcoal filter or PVC filter after which water is supplied to the storage tank.

2. The UVPCE located at latitude 23.528oN and longitude 72.458o E, about 12 km away from

   Mehsana. While UVPCE is on 25 acres, the entire educational campus contains more than 300 acres. The campus holds separate hostels for male and female students and offers dining and shopping facilities.the area of roof top of UVPCE building is

   2700m2. And annual rainfall in GANPAT

   university is 980mm .(source: data obtained GANPAT university itself).

   Figure 2 plan of UVPCE building

3. METHODOLOGY

   Figure – 3 Methodology

   1. The rainfall intensity is taken as 30 mm per hour.

   2. Area of roof top.

      The area of roof top UVPCE building 2700m2

The methodology for the planning and designing of RRWH system is explained in following steps; 1)Select the appropriate path of pvc pipe connecting the storage tank.

1. The area of UVPCE building is calculated

   and the planning for horizontal drain pipe on wall or gutter at the edge of sloping roof and vertical drain pipe on wall is done.

2. Area of roof top increased 19% for pitch more than 28o.

3. The pvc pipes below ground are designed for the corresponding discharge and location of the water tank.

4. Design calculation of water tank; Water available from roof =

Annual rainfall (in mm) X Area of roof (in sq m) X Efficiency of the collecting system

The average annual rainfall of the region is 854 mm. The roof area is 2700 m2. The efficiency of the system is considered as 85%.

Water available from roof = 0.980 X 2700 X 0.85 = 2249.1 m3

So, the desired capacity of the storage tank is 2249 m3.

Also it is suggested to collect the rainwater during megha nakshatra separately for the drinking purpose, as the rain in megha nakshatra ( end of August ) is considered beneficial and pure as per Hindu culture.

Here we design for 50,000 liter capacity water tank. So the 25,000 liter of 2 tanks should be provided.

Figure 3 provision of water tank in uvpce building.

Conclusion:

With help of data collection and analysis of UVPCE building, the roof top water harvesting is perfectly suitable for 2700 m2 area. so we will

collect 50,000 litre water in 2 tanks (p.v.c circular) during rainy season which can be useful for gardening purpose as well as drinking purpose in worst condition .

1. www.wikipedia.com

2. Rain Water Harvesting Tamilnadu state Government, India. Retrieved 23 January 2012.

3. Dr. Arun Kumar Dwivedi, Virendra B. Patil & Amol

   B. Karankal, Global Journal of Researches in Engineering Civil And Structural Engineering

4. BIS (1742-1983), Code of Practice for BuildingDrainage, Reaffirmed in 1996, Bureau of Indian Standard, Manak Bhavan, 9, Bahadur Shah Jafar Narg, New Delhi, 110 002, 1996.

5. CGWB (1999), Activities and Achievements of Central Ground Water Board on Rain Water Harvesting and Artificial Recharge, Central Ground Water Board, Ministry of Water Resources, Government of India, New Delhi, 1999.

6. Garg (2006), Santosh Kumar Garg, Sewage Disposal & Air Pollution Engineering, 18th Edition, Khanna Publishers, 2-B, Nath Market, Nai Sadak, Delhi-110 006, 2006.

7. Gould et al (1999), Gould, John and Nissen- Petersen, Erik, Rainwater Catchment Systems for Domestic Security, London, UK, Intermediate Technology Publications (ISBN 1853394564), 1999.

8. Jacob (2008), Rooftop Rainwater Harvesting for Rural Schools in Karnataka Experiences, Solution Exchange for the Water Community Consolidated Reply Query : Compiled by Nitya Jacob, Resource Person and Ramya Gopalan, Research Associate, 9 May 2008.