The New Indian Express 26.08.2010
Metro Water focused on RWH: Expert
CHENNAI: Depleting water bodies and dipping groundwater table have prompted Metro Water to focus on rainwater harvesting to help meet the water necessities of the city, an expert said on Wednesday.It all started in 2003 when the AIADMK regime began to implement rainwater harvesting schemes and helped solve the crisis as the groundwater table started to rise. Even the temple tanks in Mylapore and Tiruvanmiyur were again filled with water in 2005, also due to bountiful rains, pointed out Sekhar Raghavan, director of Akash Ganga Rain Centre.
“If the groundwater is brackish, harvesting will reduce the salinity. It will also help leach out the salts in areas where the water is yellow due to presence of iron salts, and lead to clean water availability in the long run,” he said, while speaking at a function on rainwater harvesting at Metro Water’s Zonal Water Board.
Raghavan said rainwater harvesting system comprises components of various stages: transporting rainwater through pipes or drains, filtration, and storage in tanks for reuse or recharge.
In urban areas, rooftop rainwater could be conserved and used to recharge groundwater. This approach requires connecting the outlets pipe from rooftops to divert the water to either existing well/tube-wells/ bore-wells or specially designed wells/structures. The urban housing complexes or institutional buildings have large roof area and could be used for harvesting the rooftop rainwater to recharge aquifer in urban areas.
Raghavan recalled that most Indian cities were self-sufficient in meeting their water needs not long ago from the extensive water bodies. “Today, rapid urbanisation has resulted in people encroaching upon lakes and building houses,” he noted.
Metro Water area engineer M Lokanathan said one could now strike water in Chennai after digging within seven to eight metres. This was important, given that Chennai did not have perennial rivers, he added.
