Drains, Mithi to be widened in another 3 yrs: Civic body

Mumbai: The civic body has said that Mumbai's storm water drains will be widened and deepened by 2015, as will be the city's most abused river, Mithi. The cost of the venture, in the end, will come to about Rs 3,900 crore. 

    Municipal commissioner Sitaram Kunte said that, through the BRIMSTOWAD project, the BMC is quadrupling the holding capacity of storm water drains and supporting that with pumping stations to prevent a repeat of the 2005 floods. "We have planned for a rainfall of 50mm/hour and runoff coefficient of 1, as recommended by the Madhav Chitale factfinding committee. But there may be days when it rains more; no system can be calibrated to take care of all eventualities," Kunte added. 
    The civic chief said pumping stations are being constructed in two phases. "The Irla and Haji Ali pumping stations are complete, while work on Love Grove and Cleveland stations at Worli is underway. Tenders have been invited for the Britannia outfall pumping station. In case of three other stations (Gazder, Mahul and Mogra), there are land and environment issues that need to be resolved." 
    But, according to hydraulics expert Madhav Chitale, the implementation of BRIMSTOWAD is the least required to protect Mumbai, which is now a risk-prone zone from "hydrological point of view". "Mumbai needs a three-way approach. It has to be probabilistic and not deterministic. BRIMSTOWAD is a deterministic approach," he said. 
    Chitale pointed out that his report had recommended categorisation of floodprone areas on the basis of the possibility of their flooding "once in 10 years, 25 years, 100 years and above 100 years"—also known as the river valley approach. In the first category, he said, residents must be asked to take compulsory insurance. Another desperately-needed measure is the preparation of a climatic model to determine rising sea levels. "Orissa has done such a study. Mumbai must also study the impact of sea rise. There are 40 points where water from the city flows into the sea. Protection bunds need to be redesigned at these points." 
    According to storm water drain department officials, of the 55 floodingprone spots, inundation has been stopped in nine and reduced in six others, thanks to pumping stations. The Love Grove and Cleveland pumping stations will ensure there is no flooding in another nine spots, while Britannia, Gazder, Mahul and Mogra will stop flooding in yet another 24 places. 
    Activists argue that it is not enough to merely widen and deepen nullahs and rivers. The city's open spaces must be saved as well since these act as holding ponds in case of floods. 
    Rising concretisation of open spaces in housing and commercial complexes has increased the runoff, preventing water from percolating into the ground. Similarly, saltpan lands and mangroves along the coast must be protected, activists say.