It is heartening to see that we have a proactive government responding to the water crisis looming ahead through direct action.
The Jalsanchay Yojana of Gujarat government is aimed at water conservation through deepening of waterways and water-bodies with a simple and plausible assumption that deepening will result in increased water retention.
Unfortunately, while intentions are good, there is a possible devil lurking in the detail, and to understand this, we need to look at how earth deals with water.
Apart from few rare continuously rocky areas, most of the landmass of Earth is either porous or fractured. So, rainwater falling on land that doesn’t travel down a water-course enters deep into the ground and interacts with underground geology of earth forming what is known as aquifer.
Aquifers are like underground rivers or water-bodies where a huge amount of fresh water of earth is stored.
If we return back to earth and look at water bodies that are getting deepened right now, the reason why they retain water and prevent it from percolating into the aquifers is because of a specific reason that appears to have escaped the attention of the experts who have designed the Jalsanachay Yojana for the state.
As water runs off the ground, it carries small particles of earth that slowly get deposited on the bottom of a water-body forming a layer of clay. As clay particles stick together very well, they form an impervious layer at the bottom of a water body and prevent water from traveling into the ground.
So, when you deepen a water body by digging, you end up breaching this protective bottom layer of clay. Once clay layer is broken, water retention capacity of the water body will be drastically reduced.
It is my personal belief that Jalsanchay Yojana may end up with a counter-productive result of water bodies drying out sooner than before in the next season. And yet, I feel that it could actually be a blessing in disguise for us.
Though water bodies will fail in holding the water, they will end up directing it underground through their breached bottoms, so we are likely to see a substantial increase in underground water tables. Jalsanchay may fail on the ground, but it may end up replenishing aquifers of the region.
As water management is primarily focused on what we can see, comparatively less attention is given to an even larger reserve of fresh water on earth that is hidden underground in aquifers.
Though we have been using bore-wells extensively, we have still not cognized the need of creating a robust and detail map of all the aquifers of the state. A pilot program of aquifer mapping supported by world-bank has already started in some states of India, but there is not enough work done on aquifers in Gujarat.
As water management is existentially critical for the state, I don’t see why we need to wait for external support for this research work that has potential to solve the largest problem faced by the state. Gujarat needs to invest its own resources and commence a state-wide aquifer mapping program starting from drought-prone regions.
While we invest heavily in building overland canals and waterways, we are failing to realize that aquifer-based water management may be an even better method of dealing with water, as underground water-bodies come with some additional advantages too. They evaporate less and they surely don’t provide breeding facilities to the dreaded vectors that are becoming a great threat to our state.
Once we are able to work out the underground dynamics of water in the state, we will be far better placed in how to distribute this precious resource.