For home-buyers in Bengaluru, a checklist to assess water security

Here is a comprehensive list of the critical questions to ask about water systems and availability, when buying a home in Bengaluru.

Sneha (name changed) decided to buy a flat in a gated community in Bengaluru this year. She was worried about the availability and sufficiency of water supply. She ticked off her checklist by asking one question to the builder: “How many borewells are there?” But could she have done more to assess water security in her new home?

“Beyond that one question on borewells, no one could ask anything more,” she says, adding: “It is hypothetical, whether these borewells would supply the required water. Everyone felt that the use of tankers was inevitable. And that eventually the government would solve the water crisis.” She adds that any apartment that offers a sustainable solution for water security will have a competitive edge in the market.

Considering the stress on water supply and the simultaneous real estate growth in the city, what should a home buyer consider about water supply and availability? If you are planning to buy a new home, what would you check to assess the reliability of water sources, water security and sustainability?

Here is a comprehensive explainer:  

Check for zoning and land use rules

  • First check if the house or apartment is built on land that is ‘for residential use’.
  • The purpose of land use is classified in the Zoning and Land Use Rules in Bangalore Development Authority’s (BDA) Master Plans for Bangalore Urban district.
  • There is a separate Master Plan for properties that fall within the Bangalore Metropolitan Region Development Authority (BMDA) limits.
  •  A residential property is legal only if it is built in a residential or mixed residential zone. Residential multi-storied apartments are, however, allowed in commercial zones.
  •  For apartments and individual houses, you must have a Building Plan Sanction issued by the BBMP, BDA or the village panchayat in whose jurisdiction the property is under. Ask if you can see the sanctioned building plan.
  • A khata certificate, issued by the BBMP, is required to apply for a water connection.

Check groundwater sufficiency: How does it get charged?

Water expert S Viswanath suggests checking if there is any lake nearby. “Even if it is a kilometre away from their apartments, buyers should enquire about the lake and see if it is in good condition because that lake will likely feed the aquifers.”

Shashank Palur, urban hydrologist, adds: Some lakes recharge and some lakes take water from groundwater table. Lakes will not immediately recharge your borewells, they will recharge the shallow aquifer.”

“Having a water body that is clean and full for a major part of the year yields benefits like recharge of the upper aquifer; this will eventually, over time, percolate deeper into the ground and recharge the borewells,” he adds.

Shashank says old areas like Jayanagar, Malleswaram, Basavanagudi, are connected by piped water supply and do not face severe water stress. “The bottom line is that there is actually a groundwater crisis. Problems are more acute in the peripheral areas of the city. There are piped water connections in central Bengaluru. For Cauvery stage 5 connections, builders have to apply to get the connection, but getting the connection, whether for an apartment or an individual house, is quite capital intensive.”

Check: Water supply maps and resources

Essential checks from a water security perspective

Viswanath also asks home buyers to make sure that there is a BWSSB connection. “Rainwater harvesting mandated by law should be in place and functional. We have seen that in many apartments in Whitefield, it is not being done correctly; it is good to ask what the law is and whether they have complied with law. Also, check if the STP is functional and what the quality of wastewater is.”

Potential buyers should look for water devices, aerators, and water-efficient showers. “They should check whether borewells are legal and fitted with meters. Find out how many borewells are working and what is their recharge structure. If tanker water comes in, has it been metered before it goes into the sump tank for distribution? They should also ask if every flat has a water meter.”


Read more: Water management: What Bengaluru can learn from towns like Devanahalli


When builders list their projects on K-RERA, they have to mention the water source. There are categories like ‘self-development’ and ‘local authority’. “If the builder has mentioned ‘self-development’ then the buyer should ask what is the source for self. A citizen is entitled to 150 litres per day, one needs to ask the builder if he is capable of providing this quantity of water,” says Shashank.

The next crucial question is if the apartment has a Sewage Treatment Plant (STP), which will reduce the burden of freshwater demand by 30% by reusing treated water or flushing and landscaping. All the new CREDAI member apartments coming up have water metering built in.

Provision for metering and STP

Water metering is an important step towards water security and reduces water consumption by about 25–30% in apartment complexes. “If all the solutions have been implemented together — STPs, rainwater harvesting and water metering — then freshwater requirements will be taken care of.”  

As per the Bangalore Apartments’ Federation (BAF)’s website, there is a Corrigendum notification that was issued by the government on 12th March 2024. This raises the minimum requirement for an apartment to have an STP up to 80 KLD or 120 units (from the current 20 units and above).

Additionally, the state government issued guidelines for sale of treated water. Apartments can now sell 50% of the excess water but the quality must meet the standards laid down by the central and state pollution control boards.

Also, treated water should be used for purposes like gardening, plantation, cleaning, servicing of vehicles, construction and commercial activities. 

Check for possible issues with rainwater harvesting

Although Bengaluru is the second city in India to mandate rainwater harvesting, there are still a few lapses. Viswanath says: “In some villas, I find that builders don’t do any rainwater harvesting at all. Storage of water as well as recharge is important. The rule of thumb is for 100 square metres a 6,000-litre sump tank should be there.”   

Shashank says the problem with the mandate is that most buildings don’t have the space for storing rainwater. “You can install a 2,000-litre Sintex tank and fill it up. You capture rain water, but there is no mandate that it should be used other than recharging through open or borewells. They put the pipes and infrastructure just so that they don’t get fined, and at the same time they are releasing rain water into stormwater drains.”

Rainwater harvesting system in an apartment
Representative image. While BWSSB has given guidelines on the capacity required for RWH structures, there is no penalty for not complying with these specifics. Pic courtesy: KSCST

Being proactive is essential

Being proactive is important to ensure water security and a sustainable water supply. “We surveyed 60 apartments in the Yelahanka zone. Three to four RWAs took a personal interest and used an automated system to run the STP, which can be a great buffer against water scarcity,” Shashank adds.

The need of the hour is an integrated water management plan. The obstacles to it, Shashank says, are how responsibilities are broken down between different agencies. “One has to go through 10 departments and the department heads keep changing.”  

Basic questions to consider for water security

  • What is the water source: BWSSB, Cauvery water connection or borewell, tankers?
  • Is there a Sewage Treatment Plant (STP)?  
  • Is there greywater recycling and piping?
  • Is it a borewell recharge well or just a few rings?
  • Are there water meters to check how much water each house/apartment is consuming?
  • What water is being used for gardening, washing cars/common areas?
  • Is there a separate storage for rainwater and greywater and separate sumps?
  • What is the rainwater harvesting system like?

Density and water supply

The residential real estate data of the city is also important to note. As per Knight Frank India’s Bengaluru Urban Flood report, the city’s land use dynamics have significantly changed due to population growth. The share of the built-up area of Bengaluru has increased from 37.4% in 2002 to 93.3% in 2020. 

As per Knight Frank India’s report, Bengaluru South had the highest share of overall sales in H2 (second half of the year) 2023.

Parameter20232023 Change
(YoY)
H2 2023H2 2023Change (YoY)
Launches (housing units)51,12618%27,58424%
Sales (housing units)54,0461%27,7994%
Source: Knight Frank India

Micro-market split of sales in H2 2022 and H2 2023

Micro marketH2 2022H2 2023
Central0%0%
East33%32%
North13%22%
South46%39%
West8%7%
Source: Knight Frank India
Micro marketLocations
CentralMG Road, Lavelle Road, Langford Town, Vittal Mallya Road, Richmond Road
EastWhitefield, Old Airport Road, Old Madras Road, KR Puram, Marathahalli
WestMalleshwaram, Rajajinagar, Yeswanthpur, Tumkur Road, Vijayanagar
NorthHebbal, Bellary Road, Hennur, Jakkur, Yelahanka, Banaswadi
SouthKoramangala, Sarjapur Road, Jayanagar, JP Nagar, HSR Layout, Kanakapura Road, Bannerghatta Road
Source: Knight Frank India

According to the Water, Environment, Land, and Livelihoods (WELL) Labs’ Bengaluru urban water balance report, freshwater demand in Bengaluru is approximately 2,632 million litres per day (MLD). The total domestic demand stands at 1,890 MLD (the domestic demand was calculated based on a projected population of 12.6 million and an average per capita consumption of 150 litres per day). 

As per this analysis in Citizen Matters: 

  • Bengaluru East has the highest number of households. Nearly 30,000 have piped water connections.
  • Anekal, despite the highest population among the five sub districts, is at a low level of 25,475 households with piped water connections.

Also read:

Comments:

  1. B P Bhat says:

    I have done individual water metering in my apartments since 2006. And I don’t face any water problem / headaches.

  2. Very useful info and appreciate the clarity as well. Thanks

  3. Narayan Hegde says:

    What about swimming pool in the complex? And about water used for pool and regular cleaning of pool ?
    Next, there is no point having multiple bore wells. It does not help.
    Third, at what depth the borewell got water oozing out ? And us the water tested. If it is beyond 300 feet it is NOT sustainable in the long run. If the water from borewell is lab tested and contains chemicals, heavy metals then be careful about nearby industries.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Similar Story

Ground surveys crucial for validating Bengaluru’s water security index

An analysis of water usage by commercial areas would give a complete picture of distribution patterns within the water network.

Bengaluru has experienced extreme weather fluctuations this year. After a severe heatwave, the city enjoyed a brief respite with heavy showers, resulting in a record 111.1 mm of rainfall earlier this month. While Bengaluru received excess rainfall, the rest of the state is grappling with a 38% monsoon deficit, affecting water storage levels in reservoirs. The city is still facing water shortage despite heavy rains. In this multi-part series, analysts at the OpenCity water datajam, examined the level of water security (or lack thereof) in the areas/wards and provided insight into the redressal mechanisms: Part 1: Is your neighbourhood ‘water-secure’?…

Similar Story

Analysts examine Bengaluru’s water security indices and data challenges

Water usage in the city, per ward, has been determined by examining the groundwater index, land use index, and governance index.

(In Part 1, data analysts explained how they arrived at a definition of water security. In Part 2, the analysts explained the methodology used in estimating the Cauvery index and the results have been obtained. In continuation, part 3 will explain the methodology used in estimating the remaining indices and its results) Groundwater index Borewell count: The OpenCity borewell dataset was used to map borewells into Bruhat Bengaluru Mahanagara Palike (BBMP) wards and compute the number of borewells per ward. Assuming an average yield of 5,000 litres/day, water supply from borewells was normalised with ward population and the wards were…