Date: March 02, 2024
Bengaluru is facing a massive water shortage problem accelerated by the lack of rains. The Cauvery River is the driest it has been for a decade. While Bengaluru’s water problem is not new and has been in discussion for decades, we in collaboration with Open City opened public data to interested participants in order to gather insights, and bring in different perspectives. In the day-long event, 32 participants from varied backgrounds, including urban planners, GIS experts, software developers and other active citizens joined hands to analyse public data in the context of water – groundwater, rainfall, lakes, water supply – in Bengaluru. The participants were split into six teams who dove deep to identify trends and patterns to provide better insights into water supply and groundwater levels, usage and recharge, and wastewater potential in Bengaluru.
Well Labs, Bangalore Apartments Federation and Biome Environmental Trust were partners for the datajam. The event was held at mod.erate, Church Street, Bengaluru.
The problem statements for the teams were:
- Addressing water consumption needs on the outskirts of East Bengaluru.
- Evaluating the rainwater harvesting potential and costs savings in Bengaluru.
- Imagining Bengaluru without the Cauvery and the population that could be sustained in such a scenario.
- Understanding the water supply of RERA-approved projects with over 1000 units from their application forms.
- Effect of Industrial effluents on the groundwater and water sources in Peenya Industrial Area.
- Computing a Water Security Index for different parts of Bengaluru.
OUTPUTS FROM DATA JAM
TEAM 1
Abhirami, Biswa, Purva, Sankar and Vidya of Team “Jal Rakshak” looked at the water consumption needs in the outskirts of East Bengaluru and how it compares to the central parts of the city.
What they found is that, while ground water caters to 48% of Bengaluru’s needs, the recharge rates remain significantly lower than the extraction rates. Moreover in the eastern suburbs the depth at which it is available is much more than in the rest of the city. These suburbs are primarily dependent on borewells dug by communities and private water tankers for their water needs.
TEAM 2
Anvitha, Gaurav, Kedaravindan, Namoshi and Sreechand of Team “Water Warriors” looked at the potential for rainwater harvesting in Bengaluru and the economic benefits that could accrue from that.
They estimated the rooftop potential by looking at the rooftop cover in Bengaluru from Google open polygons and the rainfall data of the city. Rainfall was classified based on level of rainfall with a threshold of 30mm. The total harvesting potential was thus calculated as the product of rooftop area, harvestable rainfall and runoff coefficient. Based on rainfall from 2022, they found that 456 Million Litres per Day(MLD) could have been harvested in Bengaluru from the rooftops, which is 25% of the water demand of the city – 1890 MLD.
- Evaluating the economic incentives for implementing rainwater harvesting systems by comparing the costs of conventional water sources with rainwater harvesting.
- Estimating the rooftop rainwater harvesting potential of the region of interest.
- Assessing the cost of water from various sources (tankers, borewells, and Cauvery Supply) currently paid by households within the area of interest( for the purpose of today’s calculations the city) and comparing with the cost of water if we were to implement do rainwater harvesting in the region.
TEAM 3
Janhavi, Nikhila, Priyanka, Vaibhav and Shubham of Team “Utopia” tried to imagine a Bengaluru without water supply from Cauvery. They tried to compute what could be the population that could be supported with only local sources of water.
They propose an alternate scenario where Bengaluru is developed more sustainably and can be self reliant on water resources, including the treatment and reuse of waste water.
TEAM 4
Malavika, Rohit, Sabarinath, Upasana and Vivek of Team “RERA-vent” looked at the large projects of more than 1000 units coming up in Bengaluru and what their claims for water sources are.
They scraped data from the Karnataka RERA(Real Estate Regulation Authority) website and filtered those projects with more than 1000 units. They found that out of the 19 current projects, 7 lie outside the boundary of BWSSB limits, while 9 are on the boundary. But, 6 of these projects mention “Local Authority” as the water source while 13 mention “Self Development” as the source of water.
TEAM 5
Arundhati, Dishant, Mayuri, Namitha and Sanju of Team “Damns” looked at the effect of effluents in water sources of a highly industrialised area like Peenya. While it is known that a lot of industrial effluent dumping happens at Shivapura Lake and Peenya they tried to understand how widely the spread of the effluents happens by understanding the slope characteristics of the area.
According to the land-use maps, most of the area in the ward is given to industries. As per the economic census of 2012 most of the businesses in the area are manufacturing units and garment industries predominate among them.
Context: We know that a lot of industrial effluent dumping happens at Shivapura Lake and Peenya. We are looking to understand how widely the spread of the effluents happen by understanding the slope characteristics of the area.
TEAM 6
Aniket, Anoop, Chandana, Rithika, Swathi and Vishnupriya of Team “Vrishabhavathi” tried to quantify the water security in different areas of the city and give them a water security index. The index would be calculated based on available water supply, quality of water, consumption in the area, recharge of the water sources for that area and if there’s any reliable authority to resolve water related issues.
CONCLUSION
Most teams had unique and relevant approach to looking at the city’s water problems. While accessibility and lack of data have been identified as issues, because of platforms like opencity.in, we are able to create a community where citizens, students and experts can engage with data and expertise to generate insightful ideas.
Shashank Palur, hydrologist at Well Labs noted that “events like these are great for bringing the community together and helps them understand the problems regarding water scarcity better. It also inspires them to think of possible solutions and test their viability.”
Sindhura VS, urban designer at mod foundation, felt that “datajams and data visualisations play a crucial role in transforming raw data into meaningful narratives. They facilitate collaboration and engagement, making complex information accessible and actionable by both experts and citizens, enriching the understanding of decision-making processes within a city.”
For the participants, the experience was one of interacting with people with diverse skills and experiences. According to Priyanka Salunkhe, IIHS Urban fellow, “it has been a very valuable interaction across people from various disciplines, with very different skill sets coming together to tackle the problem of water scarcity in Bangalore by leveraging open source data.”
Sankar Venkataraman, a tech professional, noted that, “it was great interacting with people from different disciplines, some from GIS, Urban planners, techies etc. all working to look at specific water issues in Bengaluru, learning about the problems, looking at different dimensions to understand the problem, the causes and brainstorm about it and come up with plausible suggestions. OpenCity.in data has been very helpful in our analysis of the problem we took. Looking forward to more such events.”
