At Thiruvallur Sri Veeraraghava swamy Devasthanam the temple and tank are inseparable. The tank is an important site for cultural and religious activities. Earlier years the Temple tank was rehabilated by rainwater harvesting in. In turn the tank water recharges helps the groundwater recharge. Temple tanks occupy a prime position in the day to day living of the people. Water storage has been dry in the Veeraraghavaswamy Temple tank for the past more than four decades due to rapid urbanization and continuous withdrawal of groundwater. At the instance of Srimad Azhagiyasingar, the 46th Jeer of Sri Ahobila Math, it was decided to rehabilitate the tank. The sanctity of this temple tank is well established by its Name, “Hrith-Thapa-Nasini., Hrith-Thapa-Nasini is located in the very centre of the city and is the centre of age old rituals. This tank is also used for Float Festivals twice every year. These are normally celebrated at the end of the monsoon. Thiruvallur is located in regions, which get rain from the north east monsoon. Hence the first Float festival is celebrated during January and February, to thank Evvul Kidandhan for giving sufficient rain.
More than the sanctity of the holy water, the surface area of SVD tank is seven acres. The tank has been dry during recent decades due to urbanization, continuous withdrawal of groundwater and blockage of inlet systems, due to mushrooming of commercial and residential apartments in the catchment areas. Groundwater recharge has been reduced due to the increase in impervious surface from asphalting or concreting of roads and backyards. This has led to a lowering of the water table surface and has caused failures in groundwater wells. Some time earlier tank de-silting work might have been done unintentionally and substantial thickness of alluvial soil that lay over the sandy bed. From that date the tank might have completely lost its retaining capacity, and no water stood in the tank for celebrating the Float Festival.
The management approached Indian Institute of Technology to get suggestions regarding methods to improve their storage potential., Renovation commenced in 2014 with their technical support . The tank bed was covered with alluvial clay to a depth 600 mm (two feet). Deep bore wells were sunk at the tank. Due to unprecedented floods, the tank was filled with abundant water. Daily evaporation from the tank is compensated by pumping water from the bore as when required. After this, the tank became capable of retaining the water.
The photos of the tank before and after renovation is seen in the next pages.