Pumping stations with high capacity pumps will be installed at strategic locations in the city.
Mumbai, July 8 The Brihan Mumbai Storm Water Drainage Project, which was allocated an additional Rs 300 crore from the Budget, could now see a ten per cent increase in cost from the originally estimated Rs 1,200 crore.
The Additional Municipal Commissioner of Greater Mumbai, Mr R.A. Rajeev, said that given the extensive scope of work, the cost could go up by Rs 120 crore. This will be borne by the Municipal Corporation of Greater Mumbai (MCGM).
Once the project is completed by 2011, Mumbai city will be able to handle 50 mm a hour rainfall and not be paralysed as is the case each time there is a heavy downpour. The process of resettlement for hutment dwellers is also under way and nearly 1,400 families have been resettled, he added.
The project was initiated in 2007 and the Corporation received Rs 500 crore as first instalment from the Centre in 2008-09. Of this amount, Rs 463 crore has already been spent. The interim Budget that followed, earmarked Rs 200 crore and the latest, of course, is Rs 300 crore announced by the Finance Minister on Monday.
The key cost components of the project include Rs 708.91 crore for widening and deepening the 103-km network of major open drains/canals, Rs 288 crore for pumping stations and Rs 203 crore for rehabilitation of old sewage water drainage system.
In city area, pumping stations with high capacity pumps will be installed at strategic locations. Mumbai city and suburbs with 438 square km area gets about average rainfall of about 2,200 mm. Rainwater gets drained by roadside drains, minor and major irrigation canals and finally drained in the Arabian Sea and Thane creek. The drainage system is about 100 years old and can handle only 25 mm rainfall a hour.
The Brihan Mumbai Storm Water Drainage Project was conceived in 1985 as a reaction to major floods which inundated the city that year. By 1989, consultants were appointed to study the whole drainage system and only 1993 it submitted its proposal. The consultants had suggested Rs 616 crore projects for overhauling the whole system. However, the project was put on the back burner until the July 26, 2005 floods which nearly drowned the city.
According to Mr Shashikant Chawathe, a consultant and expert on drainage systems, the project report (based on which the civil works are being carried out) is old and needs to be upgraded to incorporate new data.
“The new drainage system is being designed based on flood data every six months. What is required is designing, it based on the flood data of the last decade,” he says. Mr Chawathe also believes that the July 26 flooding cannot be held as a reference post designing the drainage system as such events happen “once in 100 years”.