Angioplasty for groundwater or a heart attack waiting to happen?

The Maharashtra Govt plans to invest Rs. 800 crore to extend the 'Shirpur Model' of groundwater recharge across the state. Is it recharge or withdrawal that this model promotes?
Shirpur, Maharashtra of the 'Shirpur Model' fame Shirpur, Maharashtra of the 'Shirpur Model' fame

“What is in a name? That which we call a rose, would smell as sweet by any other”, goes the line from Shakespeare's Romeo and Juliet. There is quite a lot in a name, Juliet, especially if attaching the wrong terminology to a process is used to appropriate public funds - Rs. 800 crores, in fact. I am referring to the Maharashtra Government's decision to invest in extending the 'Shirpur model' of groundwater recharge across the state.

First, we need to understand the model, and to understand that, we need to know about the region in which it is set. 

The area 
The Shirpur pattern is named after the taluka in Dhule District, Maharashtra in which it was first implemented.

Over 80% of the state is underlain by basalt rocks which are impermeable in their pristine state. However weathering by wind and water means that the rock is permeable in several places. This permeability due to fracturing and crumbling of rock leads to infiltration of water, which further leads to recharge. The aquifer (water bearing layer of rock) lies within the layers of basalt.

On the face of it, it appears that this impermeable layer should prevent any recharge whatsoever. However, recharge of the underlying layer can and does happen thanks to weathering and fractures in the rock as explained above.

Lowering groundwater levels are not just a consequence of reduced recharge, but also due to the large-scale pumping of groundwater from different parts of the aquifer.

Location of Shirpur

The Shirpur model
This model seeks to increase recharge by artificially creating excavations along stream channels. Streams are deepened from anywhere between 1 metre to 5 metres and sometimes even deeper, down to 10 metres. Stream channels are also widened and straightened. Excavators remove the sand and silt in the beds, while weathered and fractured rock is also excavated out.

The proponents of this model liken it to angioplasty for groundwater but a cardiac arrest will be more to the point. Here's why.

Problems with the model
The proponents of the Shirpur model make two very simplistic assumptions:

  • that the basalt layer is uniformly impermeable everywhere
  • that groundwater behaves the same everywhere

The first assumption we have already spoken about. The basalt layer is heterogeneous, it is weathered, and it is fractured; all these mean that the layer does allow water to seep into the aquifer.

The second assumption is the more dangerous one.

To explain why, allow me a small detour. Have you ever wondered how a stream or river can be perennial? How does it continue to flow in summer when there isn't a drop of rain?

Dr. Himanshu Kulkarni of ACWADAM, an organisation that has been working on and studying groundwater management for decades, explains that in certain areas, groundwater actually flows out towards the surface. These areas are called discharge areas and it is this groundwater that replenishes streams in summer. This happens because groundwater more or less reflects the contours of the land around it. Since a stream is the lowest point of the landscape in any given area, groundwater tends to flow towards it. Where the water table- the topmost level of the groundwater- intersects the land, it 'discharges' as the stream flows.

On the other hand, there are certain areas which, by virtue of their underlying rock structure and their relationship to the landscape, take water into the aquifer. These are called recharge areas.

The two points to remember are that streams, in most places, are groundwater discharge areas. In some regions, parts of streams may act as recharge areas, but often only seasonally. So if one wants to feed water into the aquifer, we need to work in a recharge area, and if we want to withdraw water, we need to focus on a discharge area.

This very simple, commonsensical truth rocks the foundation of the Shirpur model.

The model claims that excavating in stream beds till you reach below the basalt layer will recharge the groundwater. We have seen that stream beds tend to collect water from the surrounding aquifer rather than to feed it.

What do you call structures that are tens of metres long, equally wide, sometimes more than 10 metres deep and collect water? We usually call them wells, but what's in a name?

The Shirpur model calls these structures 'recharge structures'. Never mind that the structures will enable the discharge of groundwater more than the replenishing. Never mind that the model encourages ‘training’, ‘desilting’ and ‘excavation’ on a large scale, thereby disrupting natural river flow patterns. Never mind that the model is encouraging the cultivation of cotton and other water-intensive, capital intensive cash crops in a region plagued by farmer debt and farmer suicide. Never mind that the process is indistinguishable from sand-mining, which has been proven to intensify flood, channel scouring ( which is the removal of sand and silt from the bed to the point of instability) and loss of habitat.

The Shirpur model is termed to be a groundwater recharge process and so justifies the investment of Rs. 800 crore. What's in a name, indeed.

The implementation of this potentially disastrous programme is made even more poignant by the fact that there is a viable alternative.

This is the process of groundwater management in collaboration with the communities who depend on it for their lives and livelihoods. It is a way to manage our groundwater resources rather than exploit it. It helps the community to understand the available groundwater resources and its issues and create practically viable solutions to sustain the supply. It looks at demand management in tandem with supply augmentation – including recharge augmentation based on the hydrogeological conditions in an area. Necessarily, it works with the full support and involvement of local communities. Managing groundwater with the complete involvement of the local communities ensures a just and fair management of this resource. It also ensures that peer pressure alone serves to keep the process alive, without the need for external monitors or other inputs.

This process is based on a few essential principles. It acknowledges that groundwater is a common pool resource, over which no single person has ownership. Just as groundwater cannot be divided among owners, it cannot be divided among users. For planning to reflect this essential trait of groundwater, the entire community needs to plan for its management across multiple uses such as drinking, irrigation and environmental requirements. Along with planning, the communities also have to manage and monitor the process though some external technical and financial assistance might be necessary in the beginning. Such a process and method of groundwater management is democratic and inclusive in spirit as well as in action.

Sounds utopian?

It has been done before, and is still being done. Watch Prajakta Jagtap of Maharashtra talk of the experiences of her village Randullabad, with this model of groundwater management.

So what do you think of the 'Shirpur Model'? Is it, as it's proponents claim, 'angioplasty for groundwater', or is it a heart attack waiting to happen?

(The views expressed here by the authors are personal, and do not reflect the positions of organisations they work with.)

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