Building India’s cities from the water up

India needs more homes in its cities. Providing decent, affordable housing is imperative as urbanisation increases.

India needs more homes in its cities. Providing decent, affordable housing is imperative as urbanisation increases. Yet one question is rarely visible in architectural drawings or municipal plans: where will all the water come from?

Water (HT FILE)

For many Indian cities, much of the answer lies underground.

Rainwater collects in cracks and spaces within layers of soil and rock. These underground stores are called aquifers. Borewells tap them for homes, businesses and industry. Groundwater already supplies half of urban India’s water.

Yet these reserves remain secondary in decisions about how our cities grow. Master plans outline roads, metro lines, sewage networks and land-use zones. Building regulations mandate height, density, parking and structural safety. Planning authorities consider connections to public infrastructure. But they often fail to start with an essential question: how much water is available, how quickly can it be replenished, and what happens when thousands more people draw from it?

This is not primarily a failure of science. India has invested in mapping and measuring groundwater. Under the Union government’s urban water programme, AMRUT 2.0, an initiative across 75 cities is helping them understand underground reserves, identify where rain can replenish them, and bring this information into urban planning.

A scientific map is useful. A process that changes where and how construction happens is transformative.

That requires focusing on the institutions shaping urban growth and the incentives driving them. Urban development agencies want housing and investment. Municipalities want to expand services despite strained budgets. Developers want predictable approvals and viable projects. Banks want to reduce risk. Homebuyers want dependable water, but may discover the cost of insecurity only after moving in.

None of these actors necessarily benefits from slowing a project to consider a problem that may emerge years later. The need for construction is immediate. The costs of water depletion arrive later and are spread among residents, neighbouring communities, farmers outside cities and future governments.

Better information alone will not be enough. Water security must help make a development easier to approve, finance, market and operate.

In water-stressed areas, major developments should require a standardised water budget: a transparent calculation of how much water will be needed, where it will come from, how much wastewater can be treated for reuse, how much rain can realistically return underground, and the development’s overall effect on groundwater.

This must not become another vague certificate or bureaucratic hurdle. The assessment should be simple and verifiable. Developers should know the standard in advance and have flexibility in meeting it.

Projects with a credible water balance could receive faster approvals, preferential access to treated wastewater or reduced infrastructure charges. Banks and housing-finance institutions could consider long-term water availability when supporting projects. Water-secure buildings could command greater buyer confidence, much as structural safety and energy efficiency increasingly affect value.

The objective is not to turn developers into environmentalists. It is to make water security commercially and institutionally relevant.

Wastewater offers an important opportunity. A modern city should not use drinking-quality water once and then pay to dispose of it. Properly treated water from kitchens, bathrooms and sewage systems can be reused for landscaping, construction, industry and cooling — reducing dependence on borewells and expensive tankers. Where conditions allow, treated water and captured rain can also be returned safely underground. More urban spaces should be designed to enable this.

Merely requiring every building to install a rainwater-harvesting pit will not solve the problem. A development can comply and still consume far more water than the area replenishes. We must plan for the shared underground reserve, not each property in isolation.

A city’s dependence on water also extends beyond its official boundary. Tankers bring groundwater from nearby rural areas. Borewells in cities and on surrounding farms may draw from connected reserves. As cities spread, concrete replaces open land through which rain once entered the ground. This network of dependence must shape decisions.

Cities should, therefore, publish understandable data on groundwater levels, quality, extraction and wastewater reuse. Major developments should disclose expected water use and how it will be secured. Residents, lenders and regulators could then see whether growth is increasing or reducing water risk.

Our experience across water-stressed regions has reinforced a simple lesson: Measurement matters, but information changes outcomes only when institutions, incentives and public accountability are organised to do so.

India does not need to choose between housing and groundwater security. It must provide both. Before the next foundation is laid, we must understand the water beneath it. India’s urban future should not discover its limits only after being built.

(The views expressed are personal)

This article is authored by Hisham Mundol, executive director, India, Environmental Defence Fund.