Bengaluru’s water insecurity is manifested in the diversity of its household water supply portfolio

Households manage their present and future financial needs using portfolios, with diversification being a key tool used to balance risks and returns. Indian households manage their water in a very analogous way to how they manage their financial and other assets. Households cope with the essential water insecurity imposed by inadequate public water supply, by investing in a diversity of water supply and demand management options. Understanding this complex household level water supply and demand balance in Indian cityscapes is essential for at least four compelling reasons:

1. To make visible the invisible: to raise the level of individual and collective understanding of Indian society’s relationship with water (an end worthy of itself).

2. To develop evidence-based policy, instead of ad-hoc, reactive policy: for example, to investigate the feasibility and potential of economic demand models in shaping water use, as in the developed world.

3. To find ‘hotspots’ requiring immediate attention: for example, households where adverse economic and environmental conditions collide in a perfect storm.

4. All hydrology is social hydrology: Consider this. We import from the Kaveri river a volume of water that is almost equal to the entire natural endowment of the city in the form of rainfall. We have completely altered the natural hydrology of Bengaluru. Any future thinking for Bengaluru must begin with comprehensive understanding of, and adapting to, this fundamental fact.

In this article, we share the first results from the country’s first statistically sound city-level survey, conducted by the IIM-B through the Bangalore Urban Metabolism Project, and ATREE. The Bangalore Domestic Water Survey (BDWS) The Bangalore Domestic Water Survey is the first statistically representative survey of household water use across the entire city, headed by IIM-B’s Dr. Deepak Malghan. Fifteen hundred households were chosen from 75 polling booths, distributed over five regions in 2013. At each booth, representatives from 350 to 650 households answered basic questions water acquisition and storage. Then, 20 households from each booth were randomly chosen for an extensive interview.

Highlights of Bengaluru’s household water supply portfolio

Nearly 85% of households use public water supply (BWSSB or CMC or both). However, public water supply is the sole water source only for 43% of Bengaluru’s households. 14% of households use only private water supply.

BWSSB supply reaches 72% of Bengaluru’s households. However, BWSSB water supply is the sole water source only for 35% (approximately 1/3rd) of Bengaluru’s households. 27% of households use other (non-BWSSB) water supply options.

Is it possible to find out the origin of water (surface and groundwater) for each water supply option?.

  • 34% of households use only surface water
  • 26% of households use only groundwater
  • 36% of households use both surface and groundwater, and in these households the proportion for each can be determined
  • In the remaining cases (4% of households), there is some amount of mixed water use. This is where both surface and groundwater are mixed in sump/overhead tanks, and it is not possible to separately account for surface and groundwater sources.

Notes:Public supply refers to water supplied by BWSSB or CMCs (City Municipal Council).

Household water supply options

This graph below shows the complete list of water supply options that emerged from the survey. Out of 23 different ways in which households were asked about their portfolio of water supply, responses covered as many as 18 ways in which households procure water. In Table 1, these 18 ways are listed. Note that since most households exercise more than one supply option, the totals do not add to 100%.

Across Bengaluru, households are using as many as 18 water supply options.

The dominant water supply option was BWSSB, piped into the yard with almost 62% of Bangalore’s households using this as at least one means of procuring water

Between 18 to 20% of households use at least one of the following means: BWSSB piped water directly into the dwelling; shared private borewells, private tankers, bottled water and BWSSB public standposts . Although the shares are the same, the kinds of households using public standposts is very different from those using BWSSB piped options and shared private borewells. The poor rely on public standposts much more than the other options which are more available to middle and upper income households.

Shared private borewell supply is much more prevalent than that of single private borewell users. This is a reflection of the fact that the modal (most frequently occurring) type of dwelling that the survey found, was that of the multiple household dwelling.

City Municipal Councils (CMCs) were the governing bodies of small towns and municipalities that got subsumed into the new BBMP boundaries a few years ago. CMC’s still provide water services to a non-trivial portion of households, notably entire from groundwater sources.

There are seven water procurement means that less than 2.5% of households use: and they are very diverse indeed. Open wells, and tankers run by the public agencies share this category. The least share is by water carts and cycles, and hospital supplied households. While the share across Bangalore of these uses is very low, these options are important for poor households.

Of the 18 water supply options, as many as 12 (or 2/3rds) of them depend entirely on groundwater. There are three options where surface and groundwater is mixed, i.e both surface and groundwater is sourced: BWSSB tankers, hospital supply and neighbours’ utilities. Surface water is only supplied by the BWSSB (piped into dwelling, piped into yard and public standpost).

In the next article, we will be sharing insights into how this and other information derived from the BDWS survey relates to what in developed countries are standard economic method to evaluate price controls on water demand. Stay tuned!