From Trickle to flood

From trickle to flood

It’s been raining cats and dogs in the City. Why don’t you harvest rainwater?

Over the last few weeks, we've been talking about the need to conserve precious resources such as water. And rainwater harvesting has emerged as a viable alternative to traditional and perennial sources of water in hilly areas, in places where the level of fluoride and arsenic is above permissible limits and in cities that battle water shortage in summer and flooding during the monsoon.

Good, bad & ugly
Bangalore has over 300 major lakes. Situated 920 metres above sea level, the naturally undulating terrain of the city, with its hills and valleys, forms a unique radial drainage pattern, which is ideal for capturing and storing rainwater.
Each valley at the ridge-top gives birth to small streams that cascade to form major stream systems in the three valleys of Hebbal, Koramangala-Challaghatta, and Vrishabhavati.
Over the years, an increase in population has led to a spurt in the number of residential buildings that have replaced traditional bungalows and their large open spaces. With the demand for land use in developed areas spiralling, vertical growth has become inevitable. This has also resulted in an increase in rooftop areas, pavements and roads.

  With massive concreting and asphalting of ground areas, the soil exposed for rainwater infiltration has decreased, leading to a drastic fall in the groundwater table and disappearance of open wells.
Over the last 30 years, Bangalore has experienced five years of severe drought and three years of moderate drought. The quest for water has resulted in over exploitation of groundwater. On an average, the groundwater level has progressively declined. Consequently, the quantity of run-off water in the storm drains has increased tremendously.
Bangalore is primarily dependent on River Cauvery, which is approx 95 km. away and 500 metres below Bangalore. While there is emphasis on centralised piped supply of water to the city, surface water bodies like lakes and tanks, which were traditional sources of supply, are on a steep decline. A conservative estimate puts the number of borewells in Bangalore at around two lakh. Usually, groundwater in shallow wells is polluted. Groundwater levels are falling due to heavy extraction and the absence of rechargeable aquifers. In fact, several deep borewells have run dry. To address the issue of water shortage, rainwater harvesting is a perfect solution.

Get the basics right
Rainwater harvesting is the process of collecting and storing rainwater in a scientific and controlled manner for future use. In cities, it includes:
  * Rooftop rainwater harvesting
  * Rainwater harvesting in paved and unpaved areas (fields, parks, pavements etc)
  * Rainwater harvesting in large areas with open ponds, lakes, tanks etc.
Rainwater harvesting potential in urban areas is huge. On a site measuring 40ft x 60ft (2400 sq ft), with an annual rainfall of about 1000 mm or 39.4 inches (Bangalore receives 1000 mm of rainfall annually), about 2,23,000 lts of rainwater can be harvested.

The amount of rainwater that can be harvested from the available rainwater in the plot depends on potential rainfall, catchment area available, collection methods and its efficiency etc.
Rainwater harvesting is a community-based programme and its success largely depends on the collective participation of everyone – from individuals to government bodies to builders to architects. With some thought and planning, you can store rainwater for direct use in tanks above ground or in underground sumps. Water thus stored can be used directly to flush toilets, water plants etc. Rainwater can be used to recharge groundwater through recharge pits, dug wells, borewells, soak pits, recharge trenches, etc.
Next week, we will see how some buildings in Bangalore have already taken the RWH route to sensible living.

Water facts
• Water supply in cities is woefully inadequate to meet galloping demand
•  Surface water is in short supply, hence the dependence on groundwater
• Due to rapid urbanisation, infiltration of rainwater into the sub-soil has decreased drastically, so recharging of groundwater has diminished
•  Rainwater, which is easily available, is an immediate source to augment the existing water supply


What you can do?
Rainwater harvesting is the smartest and most sensible solution we have to our water woes because:
 * It is environment friendly
 * It is an ideal solution for water requirement in areas having inadequate water resources
 * It increases groundwater level
 * It improves groundwater quality
 * It mitigates the effects of drought
 * It reduces the run-off, which otherwise floods storm-water drains
 * It limits flooding of roads and low-lying areas
 * It reduces soil erosion
 * It is cost-effective and easy to maintain
 * It brings about a huge saving in water and electricity bills

Freedom From Water Woes

"Freedom From Water Woes"

From paucity to plenty, a job well done!

A water story that will inspire you to conserve the precious resource

By A R Shivakumar

My earliest memories date back to a nameless lane of houses with courtyards, washed and cleaned with cow dung. When it came to big streets, there were none. There was only one road in the village of Ammanaghatta in Gubbi taluk, interior Karnataka. That is where I was raised. I vividly recall that my mother would fetch water from a nearby well.

At the crack of dawn, she would turn to her right, mumble a prayer, and reach out for two copper pots. She would paste some tamarind at the neck of the two pots, pull out the coil of rope made of coir that was hung on the wall of the granary, unlock the main door and walk to the well. That was amma and that was her unfailing routine.

There were three wells in the village: the common salt (hard) water well, the ‘Shettara bhavi’ (again, a salt water one) and a soft (drinking) water well outside the village. Much like the other women in the village, she would walk to the drinking water well, throw the rope around the wheel, and lower the smaller pot into the water. Then, she would deftly pull the rope to ensure that half a pot of water came up. After this, the bigger pot would be given a thorough scrubbing with the tamarind, and the water from the smaller pot. The remaining water would now be poured into the bigger one, and the smaller pot would be given a scrubbing.

Then she would sit by the well, awaiting her turn to draw water. She would carry the two pots - one on her waist, and another on her head - home.

After lowering the two pots next to the tiny shelf for the gods (devara goodu), she would worship the water, perform a ‘namaskara’ (bow down in obeisance) to the water and only then start her day.

Once dawn broke, my two sisters and I would wake up, pour the water from the two pots into a mud container and cover it. We would then walk to the salt water well. The stone well was 6-8 ft wide, and the water was at a depth of almost 15 ft. None of us had ever seen the bottom of this well. It was only when a pot slipped and fell into the well and Jayanna, who came to retrieve it, told us that it was 30 ft deep that we knew its depth. There was always enough water in the well for the whole village.

The neck of the well was about 3 ft from the ground. It had four stone slabs placed next to each other, and next to the slabs was a 6-8 ft-high stone pillar. Horizontally placed over the stone pillar was a wooden rafter. A wheel attached to rafter had been oiled several times, to keep it in good condition. My sisters and I took turns to draw water, go home and pour it into a big container. A mud stove was used to heat water. We would draw about five or six pots of water in the morning and after school, another five or six pots, with a ‘rotti’ and pickle to nibble at, of course! This was our ‘water supply team and scheme’.

In the village
There were two salt water wells and one drinking water well outside the village.  The ‘Gowdara bhavi’ (a salt water well) would take care of the water needs of the entire village. The ‘Shettara bhavi’ was a private one, and would cater to the water needs of a few families. The drinking water well was meant for all. Water was drawn from all these wells from dawn till 9 am, and again from 4 pm to 7 pm. I can’t remember any of these wells going dry at any point in my childhood or growing-up years.

But years later, the situation changed. Once I left the village to pursue my Engineering degree, and on my subsequent visits to the village, I realised that the water levels in the wells had dipped. People had started to fetch water from farm wells. Among the village’s more well-off men, Basavalinganna installed a pump-set to the well in his farm and with a single motor, ensured that he could run both a water pump and a flour mill to grind ragi and rice.

But once the water in the irrigation pump set (IP set) also dipped, Basavalinganna dug a new well inside the old one, and after two-three years, the water dipped again. Then came the village’s first bore well (1976). There was plenty of water and people were free to pump as much water as they wanted. No one objected.

I cannot clearly remember the sequence of events, but even as the years passed, and there was a water crisis in the village, people started to move out of their homes in the village, built new houses in the middle of their fields and started to use water from IP sets. Meanwhile, the panchayat installed a bore well and a hand pump on the lane behind the temple.

The pump was constantly used - for washing vessels and clothes, for cattle, for drinking water. There were frequent fights around the pump!

Today, all the hand pumps in the village are defunct. Bore wells are constantly installed and water is channelled into a tank, from where water is supplied to the village, whenever there is power, of course. Once the water supply begins, there are rows and rows of plastic pots lined up. Green, red, blue, yellow...

City lights
In Bangalore, I started working at the Karnataka State Council for Science and Technology at the Indian Institute of Science. My sister and brother-in-law had built a house in Basaveshwaranagar. As there was no city water supply in this locality, they had to get a bore well dug. I lived on the first floor of their house with my friends. On the ground floor lived tenants. This three-road extension with a brave house here and there, slowly grew into a bustling, neighbourhood, with a bore well in each house.

Soon, we had trouble. One day, we had a house full of guests, and there was not a drop of water. Mustering great courage, I decided to close the valve on the ground floor so that we could get some water in our bathroom! But my peace of mind was short lived as the ground-floor tenant came thundering up in a rage! The incident left me shaken. Could there be a solution to such water woes?

‘Sourabha’ is born
Around the same time, I decided to buy a plot in Vijayanagar. It was a 40x60ft plot and it was here that the foundation for ‘Sourabha’ was laid. I began to experiment with rain water harvesting on this plot. My house, ‘Sourabha’, depends on harvested rain for all its water needs. Apart from the electricity charges required to pump water, there have been no other recurring expenses associated with rainwater harvesting. We use 80 units of electricity and this includes the power used to pump water. We’ve incorporated a lot of sustainable practices, and this ensures that power is conserved. We’ve also used technology that conserves energy.

Our country won independence long ago, but I wonder how many of us have won freedom from water woes? I can happily say that I have not looked anywhere else but at the rain to fulfil my water needs. Rainwater harvesting has brought my family great benefits. I hope it brings you the same too.

GONE! Every village in India had its ‘drinking water’ well that women trudged to for a pot or two of the precious liquid. Today, Borewells have replaced ‘baolis’ and step – wells.