The Research

Groundwater: sealing the city's natural sponge

A river is more than the water you can see on top. The riverbed is a giant, invisible recharge system for the water table under the city. Recharge is rain and river water soaking down into the ground. The government's plan seals the Musi, and that waterproofs the bed. Thousands of families in the old city and in the bastis along the river draw their water from borewells. For them this is a direct threat.

The chapters

The waterproof seal: zero seepage

The government's own technical cross sections show the 70 m wide central bed paved with C.C M30 grade concrete.

The natural way: a healthy riverbed works as a filter and a sponge. Rainwater and river flow seep slowly through sand and rock and refill the aquifers below. An aquifer is the layer of water held in the ground, what people call the water table.
The concrete reality: concrete has 100% impermeability, so nothing passes through it. Not a single drop of river water will ever seep into the ground again. The 560 acres of concrete act like a giant plastic sheet laid over the city's groundwater supply line.

Deep dredging cuts into the aquifer

The River Bed Grading drawings show the natural bed level dug out to a deeper, flat level.

Lowering the floor: deepening a riverbed for grading cuts into the natural hydrological layers, the layers that hold water underground and move it.
The drain effect: a deepened concrete channel drains instead of recharging. Groundwater in nearby neighbourhoods like Puranapul and Chaderghat begins to flow out of the soil, into the deeper channel, and away.
The result: borewells run dry even during the monsoon. The bank that stored the water, the river itself, has been replaced by a pipe that carries it off to the ocean.

Concrete skips the river's own filter

Groundwater is a question of quality as much as quantity.

Bioremediation: a natural riverbed holds microbes and layers of soil that clean the water as it moves down into the aquifer. Bioremediation is that cleaning, done by living things in the soil.
Stagnant pollution: on a concrete bed the water just sits on top. Any pollutants the sewage treatment plants fail to clear stay in the water, and the soil cleansing step is skipped completely.

The cost lands on families along the Musi

Households that can afford it will buy water from tankers. For families in the bastis beside the Musi, the groundwater under their feet is the water they have.

Rising costs: as the water table drops for want of recharge, families have to drill their borewells deeper and deeper, at a cost of thousands of rupees they do not have.
Water insecurity: in a decade of climate change, a natural recharge corridor is how a city survives a drought. The government is trading that long term security for a short term "beautification" project. Concrete cannot recharge anything.

Groundwater theft

560 acres of concrete equals 560 acres of lost recharge. This project is not saving the Musi. It takes water out of the borewells of the families who live along the river to build a road for people who will never depend on those borewells. Say no to a sealed bed. Say yes to a riverbed that still soaks, and to clean water at the source.

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