Rainwater Harvesting Project Phase 2 in Rashtriya Vidyalaya College of Engineering, Bangalore

Rashtriya Vidyalaya College of Engineering (RVCE) spread over 52.5 acres is located in the Bangalore Mysore road (between Jnanabharathi and Kengeri). There are seven borewells and one open well in the campus area. Due to continuous pumping of the borewells (to the tune of 7-8 hours a day), there is a significant risk of over exploiting the aquifer. The total water consumption of the campus is pegged at around 500 kilo litres (KL) per day of which BWSSB supply is around 40 KL per day and the rest is obtained through borewells.

KPMG, as a part of its Corporate Social Responsibility program identified RVCE for implementation of a rainwater harvesting system. The first phase of this project was executed way back in 2010 with design inputs from Biome The rooftops of three blocks were tapped and directed to a 150 KL sump. This system helped the college in harvesting close to 3 million litres of rooftop runoff annually. Additionally, the overflow from the sump was fed to a recharge well which helped in replenishing the ground water table.

Buoyed by the success of the first phase, the second phase was planned with the intent to increase the quantum of rainwater harvested. This involved tapping rooftops of two hostel blocks (Chamundi and New MV Block) adding up to an area of 2439 sq m. The runoff is directed to two brick masonry filters, whose output is led to a new 50 KL sump. A 3 HP centrifual pump does duty to pump the water from this sump to one of the colleges' existing sump.

The complete system was inaugarated by officials from KPMG on the 23rd October, 2013.

This system has the potential to harvest around 1.6 million litres a year.

The open well in the campus gets the surface runoff of the campus that flows in the storm water drains. Consequently, the well is filled with all kinds of debris and is a picture of neglect in its current state. It is high time that the cleaning up and maintenance of the well is taken up as one of the main action items for the next phase of the rain water harvesting initiative in the college.

Do-it-yourself Workshop for children

Rainwater harvesting is becoming an essential tool for citizens of Bangalore. It is not only a piece of theory now, but has been practically implemented. With studies revealing that Bangalore’s lakes are mostly now sewage lakes and majority of them has just depleted has raised the concern for water to a higher extent. Biome as rainwater club provides the knowledge base for rainwater harvesting, grey water recycling as a part of responsible water management initiative. Raising awareness among people especially kids is also a part of this initiative.

This was a workshop with kids of Adarsh Palm retreat located in Outer Ring Road conducted by Subhomita Ghosh Roy from Biome Environmental Solutions on October 19,2013 from 4.30 to 6 PM. Shreya Vissamsetti a kid of Std. XII was the first one who got interested in this. We made a Tippy Tap and a Rain gauge. Tippy Tap is generally used for handwasing purpose to maintain hygiene and also it saves water while handwasing compared to normal tap water. Rain gauge is generally used for rainfall data recording purpose. A week later a workshop was organized for the kids of Adarsh Palm.

Kids were from 6-14 years. About 16 kids were present in the workshop.

Primarily it was information about water issues, purpose and utility for water management and conservation, rainwater harvesting, grey water recycling and what Biome is doing in this regard. The kids were surprised to know certain facts that were completely unknown to them. For example, they were surprised to know that how deep we need to go for searching and getting water from borewell or how rainwater harvesting is done or the extent it can help us.Next it was the turn for them to make rain gauges on their own. They were asked to get a bottle for the workshop from which they made the gauges pretty easily with the markings on it. They learned when and how this instrument is used. They also saw and used the tippy tap that was made previously. Washing hand under it was a fun experience for them.

The last part of this hour-long workshop was the quiz. There were about 20-25 questions on water awareness, water conservation, water issues in Bangalore and India, rainwater harvesting, water recycling. At the end some gifts were presented to all of them.

Rain Gauge

Tippy Tap

The making

Workshop in Progress

Quiz

Spatial mapping of Fluoride Contamination in ground water in Mulbagal Taluk, KOLAR District

A spatial map created by Ashwin (an intern who worked with us for 2 months) that plots the fluoride levels in ground water (a source of drinking water) in 280 villages in the Mulbagal Taluk. Ashwin personally tested water from each of these sources for monitoring Fluoride levels. It is interesting to see how the incidence of Fluoride is highest in the Western Part of the Taluk. Above 1ppm or 1mg/l is not permissible in drinking water.

48 villages have above 1ppm and 15 villages are critical with more than 3ppm. A portable test kit from Development Alternatives (Jal TARA) put together by the WIPRO Earthian programme was used for the testing

While it is a little clumsy the map has been inserted in full size so that all the village names are visible :)

Rainfall runoff from a Polyhouse

Commercial polyhouses are typically large and require a fair bit of water for watering the plants even in the rainy season as the rain cannot directly fall on the plants. Even a 30mm rain on a polyhouse of 1 acre (about 4000sqm) can result in a runoff of 108,000 litres (this is  equivalent to the daily water requirement of 200 families at about 500 litres per family per day). The runoff water is very clean and must certainly be put to good use. The 2 short videos capture the runoff from one such polyhouse after a short shower - so as to highlight potential for rainwater harvesting

Another innovation from Mr Reddy : A modified strainer

A design of a rainwater filter, especially for higher rainfall intensities  and larger catchments is always very tricky. Do you design for better quality filtration, easy maintainability or maximum capture of the rainfall endowment ? Of course - in an ideal world - all of the above and some more :)

The products that are currently available in the market that cater to a 500sqm rooftop  and that are wall mountable are expensive and result in a fair bit of water loss. The civil structures (storage type filters) take up a lot of space and are not easy to maintain. A small adaptive innovation from Mr Reddy addresses the above concerns. It is a modified strainer that provides a certain degree of filtration, results in no losses and is relatively easier to maintain. More details in the video

The inventor outside his home

The components of the filter

Testing for Fluoride in Groundwater in Mulbagal Taluk - a report by Ashwin (Intern with BIOME Trust)

Rainwater Harvesting in a Govt School in Bijuwara, Bangalore

An initiative by Samyukth Iyer Sequeira - a grade 6 student studying in the Singapore American School - to facilitate access to water for school children in rural Bangalore, has resulted in the commissioning of a rainwater harvesting system in Govt Primary High School in Bijuwara which is around 55 kms from Bangalore city.

The school has two one storey buildings with roof area around 1250 and 800 sq ft respectively. The village Panchayat supplies water once in around 15 days and this is stored in a sump which is around 4000 litres in capacity. There is also a surface level storage tank which currently is in a state of disuse. The daily water consumption is around 1500 litres which is mainly used for toilet flushing, vessel washing and cooking.

By tapping the rooftop from the two buildings, it is possible to harvest a total of 154 KL of water annually assuming an annual rainfall of 900 mm. The downpipes from the two building would be led to a filtration chamber which is then led to a storage tank.

Some of the work in progress pictures: