Stepwells were infrastructure

The first thing to say about Chand Baori is that the photograph is misleading. Thirteen storeys of steps descend into a square shaft roughly thirty metres deep, arranged in a zigzag that looks designed to be looked at. It was not designed to be looked at. Every one of those steps exists because the water in Abhaneri moves up and down by as much as twenty metres between August and May, and somebody had to be able to reach it in both months.

The staircase is a retaining wall

An ordinary well solves a fixed problem: dig a shaft to below the water table, lower a rope, lift a bucket. It works because the lift is short and constant. In the hard-rock aquifers of Gujarat and Rajasthan the lift is neither. The monsoon refills a fracture system a few metres below the surface; by April the same fracture system is thirty metres down. A rope that works in one season is useless in the other.

Steps are the obvious answer, and they carry a second job. A vertical shaft cut into weathered rock needs something to hold the walls in. In a stepwell, the flights of stairs are that something — they act as buttresses, each landing tying the two faces together and each flight transferring the lateral load downward and outward. The zigzag on the plan is not a flourish. It is what you get when you build a retaining structure out of stairs and want the two sides to brace each other.

So the form is over-determined before anyone carves a single figure. And then the carving goes where the structure is heaviest — the stringers, the landings, the wall faces between the flights, which are exactly the surfaces carrying the most load and therefore the thickest. Ornament settles on mass. That is the general rule of this pillar, and the stepwell is the clearest case of it in India.

Three uses stacked in one section

Read a stepwell as a section, not a plan, and three programmes appear on top of each other. The first is water: a public supply, built and maintained by a donor, usually a merchant or a queen, whose inscription names the gift and the endowment that pays for repairs. The second is shade. Because the shaft is below grade, the lower levels stay five or six degrees cooler than the ground surface in the hot months, and the landings become rooms — places to sit through the afternoon rather than pass through.

The third is social, and it is the part usually left out of architectural descriptions. In much of northern and western India, the stepwell was one of the few public places where women could gather without a specific errand. The water queue was a daily appointment. A structure built to solve a hydraulic problem therefore also produced a public space that the rest of the village did not otherwise offer.

That combination is why stepwells are large. A pure water structure would be a shaft and a pulley. A pure social structure would be a pavilion. The stepwell is expensive because it insists on being both, and the expense is legible: the number of storeys is roughly the range of the water table.

Rani ki Vav: the form at its most complete

The best surviving example is at Patan in northern Gujarat, built from 1063 and attributed to Queen Udayamati as a memorial to her husband Bhimdev I of the Chaulukya dynasty. It runs 64 metres on its long axis, 20 wide, and 27 deep, in seven levels, oriented east–west so that the first light of the day falls down the shaft.

What makes it instructive is the sequence. From the ground you see almost nothing — a low parapet, a few pavilions, no water. The descent is the content: seven levels of increasing sculptural density, culminating in a carved panel at the lowest water level. The building withholds its subject until you have walked down to it. Very few religious structures anywhere work this way; almost all of them put the god at the top of a hill and make you climb. The stepwell inverts the direction and, in doing so, inverts the politics of the climb.

It also disappeared. The Saraswati river shifted, the shaft silted, and by the nineteenth century the site was a mound. Excavation began in the 1980s; the sculpture that came out was in near-original condition precisely because it had been buried. UNESCO inscribed it in 2014 under criterion (i) and (iv). The intactness is an accident of neglect, which is worth holding on to the next time someone tells you that conservation and abandonment are opposites.

Why they stopped being built

Stepwells were not abandoned because they failed. They were abandoned because a different system arrived that was cheaper to run and easier to meter. From the 1860s, colonial engineering reports described them in a vocabulary of disease — stagnant water, mosquito breeding, unsanitary descent — and recommended piped supply and deep tubewells in their place. That judgement was partly right about public health and entirely blind to what else the structure was doing.

The tubewell won on one metric: litres per rupee. It lost on three others that nobody was measuring — recharge, because a stepwell's open shaft and surrounding tank put water back into the aquifer; cooling, because a subterranean volume is free air conditioning; and public space, because a pump house is not a place to sit. Independent India's urban growth then filled thousands of them, and the ones that survived mostly survived by being in the way of nothing.

This is the part that should make a visitor uneasy. A restored stepwell is now a ticketed monument with a lawn and a railing. It is also, in almost every case, no longer water infrastructure. We have kept the object and discarded the function, and then written the object up as art — which is a way of admitting we no longer know what it was for.

How to read one

Walk in and look down before you look at anything else. Count the levels: that number is the local water table's annual range, written in stone. Find the lowest landing — that is the dry-season water line, and it is almost always where the carving is thickest, because that is where the most people stood and where the donor wanted to be remembered. Then look at the walls between the flights: if they are blank, the water table was stable and there was money for structure but not for sculpture; if they are covered, someone was competing with a neighbouring town.

Chand Baori and Rani ki Vav are the two everyone photographs, and they are worth the trip. But the more useful visit is a small, unphotogenic vav in a village outside Ahmedabad, still holding a metre of green water in July, with a pump installed at the third landing and a woman filling cans where the carvings are worn smooth. That one still works. It is the closest thing we have to a control group.

This is entry 01 of Architecture in About India. The pillar's argument — that form follows climate before it follows taste — is set out on the pillar page.