KRG Rainwater Harvesting Foundation has implemented a Rainwater Harvesting system at Hindustan Coca-Cola Beverages Pvt. Ltd., Palakkad,in Kerala.Owing to the system, at least 71,760 kilolitres of water isgenerated within the 37.15-acre land of the factory site every year.

Before introducing the Rainwater Harvesting system, a substantially large quantity of surface water generated in the premise was rushing out without much contribution to the groundwater table of the area. It is only with the implementation of the Rainwater Harvesting system that easy natural percolation of water has become possible in the entire area.

Implementation of the Rainwater Harvesting system in the factory site included the construction of three lagoons. The combined storage capacity of the lagoons is 32,725 kilolitres. Based on the geophysical study undertaken and the hydro-geological parameters, it can be inferred that at least 50 per cent of the stored water - that is, 16,362 cubic metres - can percolate into the aquifer.

Twenty-five percolation pits have been constructed at strategic locations of the factory site for holding surface water flowing through the open area and through storm water drains.

Three large-size percolation pits near the bore wells have been constructed to recharge the deeper aquifer of the bore wells.

It was identified that an enormous quantity of roof water, equivalent to 9,120 kilolitres, could be generated in a year. Now the entire amount of roof water, which was flowing out of the site, earlier, has been directed to an underground sump for further use.

Before Rainwater Harvesting, the water column in the wells was only three metres; after Rainwater Harvesting, the water column has been recorded as eight metres. The quality of water in terms of TDS before Rainwater Harvesting was 1,500 ppm; after Rainwater Harvesting, it has come down to 1,100 ppm.

The yield of the bore wells has considerably increased. The quality of water has improved to a great extent, as well.

With the installation of Rainwater Harvesting structures in the factory site, significant improvement in the wells of the adjoining neighbourhood areas has been noted. Even a few days' downpour increases the water level and the yield of open wells and bore wells.

Coca-Cola Palakkad has become a model for the neighbouring villages to introduce similar Rainwater Harvesting structures to make their wells sustainable.

Sundram Fasteners Ltd (SFL), Padi, Chennai

SFL, Padi is totally dependent on purchased water for its entire factory, as it does not have an in-house source. It has to get water either from the CMWSSB (Chennai Metro-Water) or from tankers that supply water extracted from distant wells.

SFL spends around Rs. 3.6 million per annum towards buying of water. To bring down the expenditure, SFL assigned KRG Rainwater Harvesting Foundation the task of implementing Rainwater Harvesting in the factory site, with the work to be completed in three phases.

KRG has already implemented Phase I of the project.

Phase I involved the task of harvesting roof water, which was flowing into the drains unused.

Phase II involves the rejuvenation and recharge of an abandoned well within the SFL premises by improving its quality and yield through Rainwater Harvesting.

Phase III involves the task of collecting the entire surface run-off in the SFL site by creating an artificial pond in the northeast corner of the site.

Phase I

As mentioned earlier, the Foundation has till date implemented Phase I of the project in SFL. Thanks to the implementation, SFL was able to harvest rainwater for its use during the rains in Chennai in October and November 2002.

As part of Phase I implementation, SFL connected its entire roof area, spanning 18,000 square metres, to a storage area through pipes and rainwater collection chambers. The storage area, which is a separate rainwater-collection sump, has a capacity of 150 kilolitres. Subsequently, water is pumped from the sump to an overhead tank, from where it goes to different usage points.

Following the implementation of Phase I, SFL has succeeded in harvesting over 1,300 kilolitres of water. As a result, SFL has been able to save Rs. 52,000, due to approximately eight days of rain. The expenses for Phase I was Rs. 500,000.

The harvesting of 1,300 kilolitres of water is equivalent to the factory's five days' total water requirement. The water harvested from rain had a TDS level of 20 ppm with 7 pH value, which is purer than Metro Water and even mineral water.

Other benefits were improvement in process baths quality, lesser TDS levels in the trade effluent, sewage and hence very low TDS of treated water that is used for internal gardening.

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