Soon, drink at your own risk (ToI)

Soon, drink at your own risk Paul Fernandes, TNN | Jun 7, 2013, 02.01 AM IST Rapid urbanisation contaminating Groundwater PANAJI: The threat of pollution of the state's groundwater as a precious drinking water resource continues to loom large due to rapid urbanization sans any centralized sewage collection and treatment system. Any development in settlement areas and newer locales is preceded by the building of roads, drains and accesses, but efficient and eco-safe effluent systems to protect contamination of sub-surface aquifers is a low priority. The influx of microbial content, already a severe problem in some towns and coastal areas, is likely to worsen as the government moves slowly in installing sewage treatment plants (STPs) while the damage is being done, say sources. Urbanization in Goa has reached phenomenal levels, with the number of census towns with a population of over 5,000 reaching 56 in 2011. In addition, there are 14 statutory towns, yet sewerage treatment plants have been set up only in Panaji, Margao and Vasco. A Goa University study conducted recently in Salcete has indicated extremely high bio-contamination in the taluka's coastal belt. "Wherever the population density and the rate of urbanization is very high, the shallow groundwater has been found to be hit by bacterial contamination," explains A C Chachadi, professor of hydrogeology, Goa University. The lack of sanitation infrastructure has led to the degradation of the sub-surface environment. "The contamination due to E-coli is very high and the source is urban waste and sewage due to lack of STPs," Chachadi adds. A health department official said the bacterial analysis of water samples collected from wells in urban areas invariably show high levels of E-coli. "The drinking water should be totally free of E-coli," said the official. It is also often due to the close location of toilets-barely 15 to 20 m from underground sources of water. "Also, toilets with septic tanks and soak pits have replaced the pig-type toilets, which actually prevented damage to water," the official conceded. The soil's largely permeable nature is another major problem for setting up septic tanks and soak pits. These systems are barely adequate for small houses, and definitely not for multi-storeyed buildings. The overflow invariably seeps into the groundwater. "Hence, setting up a centralized STP is a priority in all urbanized areas, as the sewage easily percolates into the permeable soil," says Manoj Ibrampurkar, assistant professor of hydrogeology at Dhempe College of Arts & Science, Miramar. The blunder of allowing multi-storeyed buildings without plans for adequate sewage treatment on the ground hit home hard around 2000 when pollution of a few wells in St Cruz even shook up the state judiciary at the highest level. The high court of Bombay at Goa took cognizance of newspaper reports about the sewage pollution of wells from primitive systems. Sewage & Infrastructure Development Corporation of Goa Limited is pursuing projects for setting up STPs in Sanquelim, Mapusa, Ponda, besides upgrading infrastracture in Margao and Vasco, but these projects are moving at a slow pace. In the landmark order in the suo motu writ petition the high court had directed planning and development authorities not to increase the floor area ratio (FAR) for constructions as it would put pressure on the already overloaded sewage system. But authorities appear to have forgotten this directive. The state has a few areas with high potential for groundwater development, a joint study by the state water resources department and the central ground water board, south western region, Bangalore, had found. Sampling of water in various parts revealed that the water is largely free of contamination. But the study did not cover problem areas, especially industrial estates and some coastal villages. It however found that barely 33% of the state's total groundwater resources are exploited. The net annual groundwater availability as on March 2009 was 132.74 million cubic metres (MCM) while the gross annual drawal is 43.83 MCM. The net available resource for future irrigation development is 81.69 TCM. The threat of sewage influx in pristine areas with freshwater sources under the sway of a construction boom is raising concerns. "It would be difficult to provide STPs for all towns," concludes Chachadi http://timesofindia.indiatimes.com/city/goa/Soon-drink-at-your-own-risk/articleshow/20468498.cms