Do or dry: Lessons in RWH - Probably world’s biggest!

Do or dry: Lessons in RWH - Probably world’s biggest!

Reeling under water shortage, over 23,000 rural schools in the State of Karnataka began to harvest rainwater. The results are amazing!

If public water supply in most Indian cities is unreliable, the situation in our villages is far worse. Hence rainwater harvesting (RWH) is not only the ideal solution but also the most sustainable one.
Rainwater harvesting entails the collection of rain, where it falls, in a scientific and controlled manner for future use. RWH consists of roof-top water harvesting, water from open areas such as paved ways, parks, roads, fields and in lakes and ponds.
Among the three projects initiated by the Karnataka State Council for Science & Technology (KSCST), ‘Rainwater Harvesting in Rural Karnataka’ is probably the most ambitious and successful RWH project in the world.
Funded by the Rural Development and Panchayat Raj Department (RDPR), Government of Karnataka, the project studied all government schools of Karnataka for water availability, quality (fluoride contamination) and proximity to a secondary water source. Under this programme 23,683 schools were identified, in the first phase, to provide drinking water through roof-top rainwater harvesting using a very simple yet robust system. Generate safe drinking water from the school roof itself.

* Roof-top rainwater is collected and channeled through PVC pipes.
* A first flush separator is part of the pipe line, which allows the rainwater to be flushed out with the contaminants on the roof and subsequent, relatively cleaner water, to pass through sand-bed filter to be stored in the tank.

Design-wise!
The tank and the sand-bed filter are carefully designed in order to maintain the quality of harvested rainwater. The surface tank is deliberately built without a direct manhole, and one or more taps are provided at the base of the tank. This prevents sunlight from entering the tank (the presence of sunlight and air leads to the growth of bacteria, algae etc). The absence of a regular manhole prevents removal of water by dipping vessels, and also prevents lizards, cockroaches and dust from entering the storage tank. The bottom of the sand-bed filter itself is fabricated as a manhole with perforations and can be removed to clean the tank when the sand bed is removed for periodic cleaning.
The size of the tank and the pipes for collection from the roof are designed using the parameters like local annual rainfall, seasonal variation, number of students in the school and roof area available.

The rainwater harvesting experiment is a thumping success in almost every rural school in all the 29 districts of the Karnataka state. Not only because it has solved the schools’ drinking water problems, but also because it carried home an important social message. The children, who have witnessed the traumatic effects of fluorosis — caused by contamination of bore well water — have become ardent converts to rainwater harvesting. They get a liter of harvested rainwater in school every day and, in many houses, rainwater harvesting has become a way of life.

The simple technique of sand-bed filter and locally available material to build the storage tank ensures that costs remain affordable.

One success story in a school will etch the impression on hundreds of young minds to educate their parents each year on sustainable rainwater harvesting.

At this school in Tumkur District, the students get a liter each of harvested water, every day

A Rainwater Harvesting Demo in progress at KSCST, IISc, Bangalore

      

RWH in a large urban school

Principles of RWH are set in stone in a school in Koppal District of Karnataka State

Create your own Underground Lake - almost free of cost

 “Create your own Underground Lake” - almost free of cost

      

Ground water Recharge – One time investment, Lifetime Advantage, No replacement, No maintenance!

You do it today, influence all your neighbors tomorrow and if you are lucky,

you will have pure water sparkling in your own well!

Rainwater from roof tops of buildings, roads, payments, playgrounds and many such surfaces flow out of our city in a normal course. Most of us neglect this precious water and may consider this as a nuisance!

Simple interventions which you take in your house or your premises will make a sea change and literally you can create your own underground lake.

Divert rainwater in to an existing old well, even if it is dry. Make sure the rainwater is filtered to avoid debris to enter the well.

or

You can create a cement ring well. Cement ring wells can be built by digging the ground (circular shape of 3 or 4 ft diameter) to the required depth (minimum 10 feet) followed by inserting precast cement rings to avoid caving in of the side soil. Fill up the remaining excavated pit around the rings with jellie (aggregates or boulders). Do not fill anything inside the cement rings. Rainwater may be allowed directly into the well for ground water recharge. 

Ground water recharge can also be done through check bunds, infiltration trenches and infiltration galleries.

Rainwater from the well passes through many layers of soil and will reach the water table to create large underground lakes.

“We are giving back water to our mother earth”

You do it today, influence all your neighbors tomorrow and if you are lucky,

you will have pure water sparkling in your own well!

Excavated well , Cement rings ready for installation . 

Cement rings inserted ,  aggregates filled around the rings . 

Cement ring well for surface recharge .

Cement ring well with safety grill for roof top rain water recharging .

                                 

                                     

                

Your own funnel to recharge roof water into the ground

                                   

Crystal clear - Sparkling rain in a traditional well

What it takes to go from barren to beautiful!

What it takes to go from barren to beautiful!

At Ground Zero - Rainwater save the existence of a Pharmacy College

Robinson Crusoe would have been proud of the folks at Mallige College of Pharmacy, Silvepura on the outskirts of Bangalore. In dire need of water they tried and tried to sink bore well after bore well.

Twelve bore wells had failed and their tanker bills had skyrocketed before they turned to rainwater harvesting in 2007.

Karnataka State Council for Science and Technology planned RWH and the college implemented the plan at once.

The college and hostel cover 48,000 sq mts and the roof area is 11,710 sq mts. The annual rainwater potential is 13 lakh liters. For seven years now, harvested rainwater meets their needs for almost 172 days in a year.

Rebirth of a DEAD Swimming Pool

Rebirth of a DEAD Swimming Pool

Our elderly people from Bangalore probably learnt to swim in a iconic pool near Hudson circle, but where has it vanished now?

If you have ever walked into the Bruhat Bengaluru Mahanagara Palike (BBMP) office, located near Hudson circle, you would have seen a lovely garden but we you able to spot a swimming pool? Well, if you ask some old Bangloreans, they will tell you the story of the cool, deep pool where some of them learnt to swim. So what happened to this pool? That’s a long story but I’ll save you a trip to the musty archives and tell you where exactly it went.

When I walked into the BBMP office one muggy morning in 2003 (it was called the City Corporation then, (not BBMP) to meet the Commissioner, I was mesmerized by the beautiful heritage building in front of me. And on this 10 acre plot I also spotted a beautiful but dry stone bed – it was a pool built by the British for the public.

SPOT THE SECRET! The underground tank at the BBMP building has an interesting history

I actually caught sight of the changing rooms which were grand looking stone structures. They added to the aura of the heritage building. But the pool itself was being demolished because ‘vegetable vendors and other from City market were frequenting it to have a free bath’.

 I was told that the pool had become an ‘eyesore’. So, the City Corporation had resolved to demolish it and replace it with a garden. I saw workers getting ready to raze the changing rooms. Sprinting to Commissioner’s office, I requested him to save the pool – the structure, actually. He wanted to know why, I promised to give the Corporation their coveted garden if he’d give me the pool. It was a 7.5 lakh litre ready made tank and letting it be covered up with concrete would be a crime.

I told him of my plan to collect rainwater from all the four buildings – the main building, Annexe 1 and 2, and the New Council Hall – into the pool, which would turn into a tank. I planned to erect pillars and beams over the pool and turn it into a garden. I was lucky that The Commissioner agreed to the plan and stopped the demolition with a stroke of his pen.

The result: The heritage buildings remained untouched in the first phase of RWH project. And rainwater from the Annexe buildings flows into the pool which functions as a tank and is full as it was decades ago.

IMPRESSIVE!  The BBMP building near Hudson Circle.

No more dry spells at DHOBI GHAT.

No more dry spells at DHOBI GHAT.

All good omens for the dhobi ghat and the residents of Malleshwaram area in Bangalore.

Of the many dhobi ghats in Bangalore, the one is Malleswaram is spread over six acres. It lies in the downstream of Sankey Tank. This dhobi ghat was once a natural water body. Decades ago, it was converted into a dhobi ghat, where 250-300  workers wash clothes in shifts. Earlier, the sources of water were streams of the Vrushabavathi River.  

 With time, these streams dried up because of the proliferation of open wells and borewells in the vicinity. Houses and establishments upstream discharged sewage into the storm water drain which ran right through the dhobi ghat. Left with little choice, the washer men had to use polluted water, which they collected in huge ponds. They added hefty quantities of detergents and chemicals into cement-ring tanks with their bare hands, leaving them vulnerable to burns and infection. The clothes with chemicals were rinsed in the huge ponds, leaving the water even more murky and contaminated. The ponds were drained by unplugging valves at the bottom once in three-four days. The dirty water was released in to the Vrushabhvathi.

 The dhobi ghat had a huge well, which went dry 20 years ago. The BBMP got four borewells dug 18 years ago but all went dry within no time. Water was then pumped from a public borewell behind Kadu Malleswara Temple in Malleswaram and piped to dhobi ghat. Fights broke out between the washermen and the local residents. Soon, even this water yield began to decline.

Distraught, the dhobis approached Government. Government requested the Senir Scientist A R Shivakumar at KSCST, Indian Institute of Science to come up with a solution.

 The solution

The dhobi ghat has a steep slope from east to west and north to south. The tanks are built in the valley at the lowest level. The highest ridge is on the eastern side and a huge open well is located at this point. As the rainwater collection area inside the dhobi ghat is not conducive for systematic collection, it was decided to harvest runoff water from the stormwater drain on 15^th Cross of Malleswaram, starting from Bashyam Circle in Sadashivnagar. The paved road on 15^th Cross has a stormwater drain on either side that carries rainwater from east to west.

 The upstream stormwater from the stormwater drain on the roadside at the north-eastern corner of the dhobi ghat is collected with a system of first flush separator, leaf slide, silt trap and a pebble filter for subsequent storage. The huge quantity of stormwater is systematically processed.

 During low rainfall and lean flow periods, water in the storm water drain (which carries pollutants) is not allowed into the water storage system.

 During periods of heavy rainfall and higher flow, the debris, leaf litter and suspended particles such as plastic covers are allowed over the leaf slide and relatively cleaner water percolates to silt traps. The silt settles in these traps and clean water passing through the filter bed is allowed to flow into the open well in the dhobi ghat which is 60 ft deep.

 The rainwater harvested in this manner is temporarily get stored in the open well and it also recharges the ground water. The overflow from the well is connected to 4 underground sumps (of 1 lakh litre capacity each) which are built strategically in the open space located beside and behind a temple inside the dhobi ghat. The extra rainwater from one of the underground sumps is allowed to flow into one of the existing borewells for ground water recharge.

The stored water from the underground sumps is directly piped, without pumping, into the wash area as these tanks are located at an elevation.

This intervention has mitigated the water crisis to a large extent. The 60 ft deep well, which had gone dry, is now full of water through the year. Two of the four borewells have been recharged. All good omens for the dhobi ghat and the residents of the area.

Namma Metro - the biggest clean roof of Bangalore to Harvest Rainwater

Namma Metro - the biggest clean roof of Bangalore to Harvest Rainwater

Namma Metro has a potential to harvest around 300 Million Liter RAINWATER every year

Metro rail infrastructure in Bangalore has created rapid mass transport and also created one of the largest roofs in public space.

 As the metro rail viaducts are elevated and are not in reach of public or other animals, the surface is relatively clean. Also the trains are electric and will have no diesel or oil spills. The passenger cars are air-conditioned with fixed windows, which will prevent littering. This logically bring in the idea of harvesting rainwater from the largest roof of Bangalore - around 4,60, 000 sq. m.

Bangalore Metro Rail Corporation (BMRC) is one of the urban utilities to have adopted rainwater harvesting in a massive and practical way. The Metro has made simple arrangements to catch all the rainwater that falls on its station areas and use the same for non-potable uses.

 The metro Reach 1 to Reach 4 has 44 stations and 33 of them are over ground. The roof are available in these infrastructures can be of two types.

1.  Viaduct with 8.8 meter and

2.  Roof of the station above ground

The stations form a roof area at high density traffic flow and commercial activities.

The Viaduct run all along the motor roads and is elevated.

Every raindrop that falls on Bangalore roads will only go down the drain. But every drop that falls on the Metro corridor can be harvested. Each of the six stations on the Metro's operational stretch between MG Road and Byappanahalli have water tanks of one lakh liter capacity each, to store rainwater.

The rainwater from the viaduct flows in the direction of the natural gradient as of the ground / road below. The flow of this water on the top of the viaduct is directed to the centre and finally reaches the grating at the centre of the pillar.

It is proposed to harvest roof top rainwater from Stations and Viaduct. The roof top rainwater from stations is a high volume flow at a busy junction and it is proposed to channelize this water through underground pipes either under the road / foot path on inside storm water drain sidewalk. The rainwater pipes through this underground system is discharged into a system of first flush lock and filtration system underground at a nearest open space / park / playground / parking area. The filtered rainwater is temporarily stored in an underground sump. The stored water will be pumped up and taken for final processing. Similarly the water collected from the stockyards and rising range of the station is also tapped / harvested.

The stored rainwater can be treated at storing or treated on line while pumping. The rainwater being pure form of water does not have salt and minerals or chemicals which are undesirable. Treating filtered rainwater is only by chlorination to remove bacterial contamination.

The rainwater flowing on the viaduct can be handled in two ways:

1.      Collecting the discharge from pillars at ground level and laying a trunk line along the viaduct next to the pillar under the road following the centre of the gradient. This trunk line leads water to a central location at a park.

2.      Collect rainwater directly below the grading at the top of the pillars and run a trunk line in the hollow portion of the viaduct. The pipe will follow the contour and gradient of the viaduct.

The trunk line at a suitable point can be drawn out at an intersection at the top of the pillar and below the Viaduct separate intersections.

Highlights of Rainwater Harvesting @ Namma Metro:

	Metro Rail
	Total length	42300	m.
	E-W Corridor (Phase-1)	18100	m.
	N-S Corridor (Phase-2)	24200	m.
	Width of segments	12	m.
	Below ground length	8822	m.
	Above ground length	33478	m.
	Number of Stations	41	No.
	Stations above Ground	32	No.
	Each Station Roof Area	4925	Sq. m.
	Roof Area-Biyappanahalli Depot	48552	Sq. m.

The above proposal is only the suggestion from KSCST, IISc, Bangalore.

Fire Station -MAKE A RUN FOR IT!

Fire Station - Make a run for it!

The fire station at Rajajinagar Bangalore can teach you what a rescue operation entails. It can also impart valuable lessons in water conservation

Firemen primarily tackle fire accidents, right? They also help during natural calamities, evacuating people to safety. Their main job remains fire-fighting, for which water is their primary raw material. Water, in any fire station, is stored in a large underground sump. Every fire station has a dedicated, express water line provided by the Bangalore Water Supply and Sewerage Board. The service is unmetered.

 However, for months on end, a fire station may not receive a distress call. The equipment, which lies unused, may not work when required. So, mock drills are conducted every week. But mock drills consume a lot of water. 

The Karnataka State Council for Science & Technology decided to take up rainwater harvesting at the 2-acre Rajajinagar fire station as part of its work in public spaces. As fire stations do not need potable quality water, Karnataka State Council for Science and Technology suggested that the fire station harvest its roof-top rainwater.
Water collected from the roof (area 300 sq. m.) is filtered and stored in an underground sump. An additional sump with a capacity of 60,000 liter is built. This sump can fill 10 fire trucks. It also nurtures a lovely garden.

Rainwater Quenches Fire

The Karnataka Fire and Emergency Services department is a department of the Government of Karnataka that is the foremost disaster management body in Karnataka, India. Among the 17 fire stations in Bangalore, Rajajinagar fire station at Rajajinagar Industrial town has implemented rainwater harvesting. The total plot of the fire station in Rajajinagar is 8, 094 sq. m. with Rooftop area of 297 sq. m. Currently the water supply to the fire station is from BWSSB and borewell meets the per days demand of 5, 000 liter. Existing 60,000 liter sump will be used to store rainwater.

The rainwater flowing through the down water pipes is filtered through four PopUp filters and stored in an existing 60, 000 liter underground sump. With 971 mm average rainfall of Bangalore, the total annual rainwater potential from roof area of 297 sq. m. is around 2, 16, 000 liter.  The water stored in the underground sump is being subsequently used for secondary purpose like gardening, washing, flushing, vehicle washing, fire fighting, equipment, etc., The total roof area of the building is 297 sq. m. and the annual potential of rainwater is around 2, 16, 000 liter. With existing Underground sump storage of 60,000 liter. in total for rainwater, the total requirement of 18, 25, 000 liter is being met for 54 days in a year.

Vidhana Soudha - Miracle in Stone, Brick and Mortar

Vidhana Soudha - Miracle in Stone, Brick and Mortar

Vidhana Soudha is very, very special, especially to someone obsessed with roofs and walls and drains! Go around the entire building and you will not see a single rainwater pipe anywhere. This is because Vidhana Soudha has been designed as an inward-looking building, which means that water flows into the two courtyards.

There are down water pipes on the walls of these courtyards. Rainwater is discharged at the ground level and goes into an underground drain. But again, no one seemed to know where this drain is located. I nosed around and discovered a well-formed tunnel, again 15 ft below ground level, towards the southern side of the building. But my joy was short-lived. I couldn’t find the exit point of this tunnel and I couldn’t find any drawings of the building’s drainage system.

However, all that scrambling on the roof of the High Court had taught me some valuable lessons! I took a few bottles of blue ink, mixed it in buckets of water and poured the coloured water through the down water pipes in Vidhana Soudha. Again, I went around the building to see if I could catch sight of the inky blue trail!

And here’s what I discovered:

·         There are no drains within a 1/2-km radius of Vidhana Soudha. But 1 ½ km away – at Century Club’s rear gate – the tunnel that I discovered opens! The inky blue water had started coming out of this drain, a good 1 ½ km away, after 30 minutes of my having poured it down the roof of Vidhana Soudha!

·         Unfortunately, the water had got mixed with sewage and discharge from nearby canteens, rendering it useless. Treating this water would be like treating sewage!

Returning to Vidhana Soudha, I decided to collect rainwater in a ‘ring main’ inside the building. Vertical pipes were interlinked on the walls of Vidhana Soudha at a certain height above ground level where they would not intercept doors, windows or porticos etc. Water from these pipes could be channeled to a filteration point, but where?

·         Water cannot be stored inside the courtyards because they have hard rock beneath the surface.

·         Water cannot be brought out of a building which has 5 ft-thick walls made of solid stone!

We were very lucky to find 2 weak points in the entire building which we exploited to the hilt!

Vidhana Soudha has a basement on the Southern side near the Archaeology Department and Treasury. Through the ventilator in the basement, we laid two 12-inch pipes and constructed filtration systems.

The water was routed underground to the garden area and collected in 2 large underground sumps – one that lies between Vikasa Soudha and Vidhana Soudha near Gopala Gowda Circle, and the other which is located next to Kengal Hanumathaiah’s statue. The harvested rainwater is used round the year to keep the gardens around Vidhana Soudha green.

Currently 50% of the roof area on the southern side of the Vidhana Soudha is being considered for RWH.  With annual rainfall of 971 mm, total roof top rainwater available per year is 53,20,000 liter.