NEW DELHI: Besides easing traffic flow, the upcoming flyovers in the city will have an important contribution to make towards conserving water. To begin with, the proposed flyover at Dhaula Kuan will be equipped with an artificial water recharge system for enhancing ground water level in the area.

Being built by the Public Works Department (PWD), the plan for the artificial recharge system at the flyover has been designed by the Central Ground Water Board (CGWB). The plan covers a total catchment area of about 13.75 hectare, and once fully functional, it will help conserve 39,244 cubic metre of rainwater annually that has until now been flowing unutilised into storm water drains.

PWD engineer-in-chief Deepak Narayan said the step was initiated keeping in mind the dwindling water levels in the city. ‘‘While rainwater harvesting has been made mandatory for all new buildings in the city, no such specification has been issued for flyovers. We decided to install water recharge schemes wherever the ground water level was low,’’ he said.

He said while the Dhaula Kuan flyover will be the first to put this scheme to use, conditions at the site of other upcoming flyovers, too, would be studied for suitability. ‘‘All projects where deep underpasses are being constructed will have the scheme in place. The flyovers at Dhaula Kuan, Safdarjung and Punjabi Bagh will have underpasses and the recharge structures,’’ he said.

Areas that have a dip are prone to waterlogging during rainy season. Recharge systems in these areas will ensure that water does not accumulate.

Experts said rainwater harvesting at flyovers is not much different from rooftop harvesting. ‘‘Depending on the quantity of rainfall, space available and the nature of the land in the area we recommend a structure,’’ said Dr S K Sharma, consultant, CGWB.

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CHANDIGARH: The owners of a few car service stations in the city, which were issued notices by Chandigarh Pollution Control Board a couple of years back, feel that the board has not been doing enough to prevent water pollution at service stations.

The board has been selective in its crusade. Otherwise all service stations with washing facility would have installed water treatment plants,” says of the owners. There are a total of 40 petrol pumps in the city, of which about 32 have car washing facility.

This is in addition to 17 Maruti authorised service stations, two of Daewoo, two of Hyundai, two of Hindustan Motors, and… the list is long. By a rough estimation, there are a total of approximately service stations which provide car wash facility, consuming a large volume of potable water, and leaving it polluted in the process.

Of these, only less than 50 per cent have installed water treatment plants. Initially, there was a of momentum in the pressure put by the Pollution Control Board, but then officials became selective,” says a car service station owner from Industrial Area, where unauthorised service stations have mushroomed like wild grass and go unchecked by board.

Those who were served notices by the board to install water purifying devices within a given time frame fail to understand why the case was pursued on a war footing for some, whereas others were allowed to function without any objection. “It’s not that we don’t want to fulfill our moral obligation, but, the laws must be the same for all,” comments another petrol station owner.

When Times News Network contacted member secretary Chandigarh Pollution Board, P J S Dadwal to get an official version on the number of petrol stations which have not yet installed a water purifying plant, he refused to comment, “Ours is a very small office, it is very difficult to collect this kind of figures, you can say ‘no comments’ on my behalf.”

When a car is washed, a sizeable amount of oil and grease gets mixed with water, leaving it unfit for discharge in the sewer. The Pollution Control Board had asked these wash centers to treat the water for hazardous pollutants before discharging it into the sewer. Some petrol station owners, about ten of them, went a step ahead and purified this water to a higher degree to make it reusable for washing cars and watering lawns.

Among the first stations to introduce the recycling of polluted water in this city was Col (Retd) Harjit Kapoor’s Kapoor Service Station in Sector 21 D. “The reusable water brought down our water bill to one-thirds of what was consumed earlier, and that’s how we recovered the cost of the treatment plant within two years,” says Col Kapoor. The simple mechanism of treating water works at two levels.

At the first, it removes the hazardous pollutants like oil and grease, then water is treated with alum and polyelectrolyte. Lastly, it’s filtered for impurities through paper and sand to make it reusable.

Ashok Kataria, an environmental engineer who designed the water purifying mechanism for these plants, says he has the technology to treat sewerage as well, but has not been approached by any of the big institutions to treat water.

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