Rainwater harvesting system model to be replicated in state, a law in the offing
The structure can help collect 831,000 liters of rainwater annually whereas the capacity of its subsurface storage tank comes to 30,000 liters. On an average, per day 600 liters of water can be drawn from the rainwater harvesting structure.dehradun Updated: Apr 29, 2018 22:10 IST
In a bid to “conserve” the fast depleting ground water in Uttarakhand, the state government will soon make rooftop rainwater harvesting mandatory for all private houses that will be built in future.
It has also come up with a model on which rooftop rain water harvesting system would be based.
“The model has been described in detail in the manual for rainwater harvesting and recharge, which was submitted to us by the state planning commission,” water resource minister Prakash Pant said.
“The proposed water conservation law and the related policy currently being framed would be based on that manual only.”
The rooftop rainwater harvesting model has been devised by state planning commission advisor HP Uniyal, who was formerly the chief general manager of Uttarakhand Jal Sansthan.
“I have already equipped my residential premises with the rainwater harvesting system based on that model,” Pant said.
Under the proposed water policy, it would be mandatory to have all old and new government buildings equipped with rooftop harvesting system recommended by the planning body.
“Similar rules will also be applicable to all private buildings which will be coming up in future,” Pant said.
“Maps for all such houses will be passed on condition that they will be equipped with the rooftop rainwater harvesting system.”
Pant, however, said the proposed law would have no provision to penalise the people.
“Instead, there would be a provision for incentives for those who would have their proposed houses equipped with rooftop rainwater harvesting system.”
Under the new law, people owning old houses would be under no legal compulsion to have the latter equipped with the rooftop rainwater harvesting system.
The leniency “is being observed as the premises of old houses may not have enough space for a rooftop rainwater harvesting system”.
Uniyal said he devised the rooftop rainwater harvesting model during his tenure with Jal Sansthan.
“The rooftop rainwater harvesting structure was built on the 500 sq metre roof area of Jal Bhawan, the spacious building that houses the office of Jal Sansthan in Dehradun,” he said.
The structure can help collect 831,000 liters of rainwater annually whereas the capacity of its subsurface storage tank comes to 30,000 liters. On an average, per day 600 liters of water can be drawn from the rainwater harvesting structure.
As per the manual, annually, 649, 500 liters of rainwater that overflows from the structure passes into the soak pit, which helps recharge ground water.
According to Uniyal, rooftop rainwater harvesting model he has devised would help save the precious potable water which is harnessed from the fast depleting groundwater resource and natural springs.
“Replicating such a model is, therefore, a must for a state like Uttarakhand where 80% of potable water goes waste in flushing toilets or in activities like cleaning and gardening,” he said.
“All such activities can be carried out using rainwater, if rainwater harvesting model is properly replicated.”
Uniyal said only 5% of the total annual rainfall of 74876.2 billion litres is consumed through drinking, irrigation and industries.
“The remaining huge quantity goes waste as the run off results in depletion of groundwater and natural springs,” he clarified.
“Conserving the run off through a mechanism like rooftop rainwater harvesting could help prevent the recurring water crisis in the state especially during the lean seasons.”
Uniyal also underlined the need for reviving the age-old indigenous system of rainwater harvesting by digging earthen ponds, which helps recharge ground water rejuvenating natural springs.
“Artificial recharge of ground water could also help augment water levels in the streams originating from the region,” suggested the manual for rainwater harvesting and recharge authored by the planning commission advisor.
The flow in natural springs and streams, it notes, has “declined sharply in recent years due to the accelerated deforestation caused by construction of roads or factors such as development or forest fires”.