Today we went to south eastern Bengaluru to meet with Neelima at Madiwala Lake. There we met with a well digger, Ramakrishna, who had been instrumental in digging several new wells and deepening another in the area. The first well was used for the nearby public bathrooms and for landscaping. The well was also used to recharge the groundwater by directing the rain from the bathroom roof into a silt trap and then into the well. When we looked in the well, we noticed that there was a small amount of leafy debris that had gotten through the mesh covering the well and was floating among a murky film on the surface. Ramakrishna was frustrated to see the well that he had worked so hard on wasn’t being properly maintained. He pointed to the bathroom roof that had leaves and foliage on it indicating that the lack of maintenance extended beyond the well. The vegetation on the roof, he explained, would block the gutters, clog the silt trap, and lower the water quality in the well if not cleared off before a rain.
Ramakrishna peering into the well with film floating on the surface, foliage on the
bathroom roof that needs to be cleared off.
We wanted to record some data about the well including water depth below ground level, well depth, well width, TDS (total dissolved solids), well use, etc. Neelima had brought a TDS meter, and we already had a tape measure, but we had forgotten to bring anything to collect a water sample with. A brief look around found the bottom of an old plastic bottle and some twine that we used to lower the bottle into the water. The TDS was slightly above optimum range but the water smelled clean, albeit slightly discolored. We measured the rest of the available data and asked Ramakrishna about the soil conditions he encountered when the well was dug. I was impressed by his detailed memory and knowledge–even a year after he had dug the well.
Measuring the TDS of the first well and looking out over the beautiful Madiwala Lake
As we walked to the next well by the lake, Ramakrishna quickly passed us on his motorcycle. I was a bit surprised as he rode past the park entrance onto the smaller pedestrian path just past the park security guard. Neelima explained that the entire community loved Ramakrishna because of the wells he had dug in the area, they would let him do anything. The next well had a beautiful square stone wall covered with a metal grate and more mesh to keep leaves out. When we got there, we saw Ramakrishna sweeping all of the vegetation off of the mesh to ensure that it was clean. Neelima said that he regularly will return to wells he’s worked on, unpaid, just to make sure they are being maintained and to offer advice to stakeholders if the wells needed anything. We measured the water elevation and Ramakrishna turned on the submersible pump to get us a water sample. He guided us around a building, showing us another recharge well he’d dug. Before we left, we took several photos of us standing in front of the stone well.
The water at the second well looked much cleaner-and had a lower TDS. Group photo of us with Ramakrishna.
We walked to a nursery where we saw the last well near the lake. He had remodeled it from a shallow recharge well into a deeper well that could be used to water the nursery’s plants. It was 10 feet in diameter and Ramakrishna explained what we couldn’t see; during the rejuvenation, in addition to desilting the 10 foot well, Ramakrishna had dug a smaller 13 feet deep, 5 foot diameter well in the bottom of the original well for a total depth of over 20 feet. As if to illustrate this, The nursery worker came over with a piece of string tied to a rock and lowered it into the edge of the well to show us how deep the water was. There was only 3 feet of water. Ramakrishna took the rope from him and swung the rock out to the center of the well, dropping it with a splash. It sank much further, proving the presence of the smaller well. When he pulled it up, he measured the length of the rope by holding it up to the tip of his nose. When I laughed, he looked at me and said “five feet” and indicated he wanted me to check. I used our tape and measured 5’ on the nose–excuse the pun.
The 10 foot well with the submerged 5 foot well in the bottom.
Neelima joined us in our taxi and directed our driver to a delicious restaurant for breakfast where we were joined by Ramakrishna. The food was amazing. During breakfast, Ramakrishna scrolled through photos on his phone, showing us different wells he had dug and examples of different soil types he had encountered while digging some of these wells. In one example, he showed a photo where the well had been dug through 8 different vibrant colors of soil in only a few meters depth. Another showed a unique well he had dug with a local university to gather samples of buried flora from differing depths. A photo looking up from the bottom of a deep, narrow well proved that this wasn’t an occupation for the claustrophobic.
After breakfast we went to what is thought to be one of the oldest wells in Bengaluru. It’s an unassuming stone well nestled between small homes next to a busy street. It was covered with a rusty metal grate and had litter floating in the water inside. Ramakrishna explained he had planned to remove the garbage and desilt the well in the past few weeks but due to an electrical problem with his pump, he had been forced to postpone and hoped to get it done next week. We again measured the TDS and water level, this time putting a small amount of water in a bacteria testing vial to determine if the water is safe, as the community would like to use the well water for drinking. The water in the vial should turn black within 48 hours if the water is unsafe.
The old stone well, a sample of the water we pulled from it, and the bacterial testing vial.
Lastly, we went to the home of an IT worker who had contacted Biome about groundwater seeping into his basement garage. The home was constructed 10 years ago and the entire neighborhood is built on a filled-in historical lakebed. During construction, two borewells were dug to depths over 900 feet, and both were dry, indicating that the deep aquifer is very far below the ground surface. Due to groundwater encountered during construction of the home and the presence of a shallow aquifer, an open well had also been dug to provide water for construction which is still used for flushing toilets and landscaping. Neelima suggested having the well water tested to see if it could be used for more activities such as cleaning, laundry, and possibly even drinking after minor filtration. Any additional water that could be used out of the well might lower the groundwater and potentially eliminate the seepage. Other options that were discussed involved much more work and the associated cost could quickly skyrocket.
As we left the home, we saw a water truck delivering water to homes just up the road. It was fascinating to see multiple different water issues all in one small area: dry bore wells, flooding basements, and a lack of available water requiring the truck. It was a fitting finale to a day where we’d seen wells in various stages of maintenance being used to manage water sustainably in several different ways. I think we all gained a greater appreciation for some of the water problems facing Bengaluru and some of the solutions being implemented.
Before we said goodbye to Ramakrishna, I asked about worker safety. How does he check for bad air before descending in a well? He explained they lowered a lit candle, if it stayed lit, that meant there was oxygen and it was safe. I also asked how he ensured that the wells won’t collapse on his crew as they are digging. He replied that well diggers understood the stability of the soils that they work in. They could tell which soils risked collapse and which were safe. They know the geology of the areas that they work in to such a degree that they can generally anticipate if a well can be dug safely and even provide an estimate as to the depth of well needed to reach groundwater. He mentioned that they appreciated harder soils even though it required them to use heavy metal bars to break up the ground, as it meant the soil wouldn’t collapse.
I find myself wondering how we can best capture and record all of the information that the well diggers have. Their knowledge of the different soil types, the geology under Bengaluru, the understanding of how and where groundwater flows under and through the city. How can their experience be shared with others working in the field to maximize efforts to bring about sustainable solutions that can be used to solve the problems that we are facing. The amount of expertise that is available is staggering, and it would be a waste to not take advantage of it or, even worse, lose it.
A water sample was taken from the old well at 12°53'55.2"N 77°36'56.8"E and used for a bacteria test:
After 48 hours
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