Lessons to beat the flood

MUMBAI: The monsoons may be on their way out, but they create a nightmare for the civic authorities every year between June to September. Mumbai chokes, puffs and comes to a halt during these three months.

Going the Shanghai way has become the talk of the town experts say that the road to sustained development does not lie in blind emulation or political diktat. It lies in choosing and learning from the ‘tried and tested’ models of cities, which have had similar concerns but over a period have managed to address them successfully.

ET takes a look at how three cities in Asia-Pacific are tackling the problem of flooding. Osaka in Japan sits on an ancient floodplain formed by the Yodo River and other smaller rivers, and with the exception of the Uemachi Plateau, is comprised of mostly flat low-lands.

These topographical features make the city susceptible to flooding. Because of this, in over 90% of the city area, storm water is discharged into the rivers and sea by pumps. The Osaka Municipal government has constructed the Naniwa Grand Floodway — a 12 km, 6.5m inner diameter, 30m underground channel that has a storage capacity of about 3,00,000 cubic metres. Simultaneously, the government has also built the Tosabori-Tsumori Trunk Sewer.

This large-scale trunk sewer, of a total length of 6.7 km and maximum inside diameter of 6.25m, is powered with a pumping station with a large capacity of 87 metre cube per second. One metre cube is one thousand litres. Moreover, the government also built the Yodo grand floodway and additional trunk sewers to increase storm water flow and reduce flooding.

Regular flooding affects almost 25% of Jakarta’s 650 km area. To counter this, the Indonesian capital has invested in a $588.2m flood control project which is scheduled to be completed by ’07. Under this, the East Flood Canal and the existing West Flood Canal will create a semi-circular canal that will take water from 13 major rivers which originate from the highlands of West Java flowing through the city and thus prevent flooding.

Melbourne, too has its own share of flooding problems with overflows from the Yarra river which flows right across the heart of the city. To solve this, a clear set of roles and responsibilities have been set between the Melbourne Water and local government for flood and drainage planning.

In Mumbai, the government is seriously considering The Brihanmumbai Storm Water Drain (BRIMSTOWAD) project, but till date only 40% of BRIMSTOWAD has been implemented at a cost of around Rs 290 crore.

In August, the government appointed a committee under chairmanship of Madhav Chitale to study the reasons for flooding and suggest remedial measures. The committee is expected to submit its report by October-end.

“Mumbai today is suffering from the LIMP syndrome. Primarily, spread over 437 sq km and surrounded by sea on all sides, there is shortage of land (L) and the city can expand only vertically, not horizontally.

Secondly, there are almost 7 different institutional (I) set-ups which work at cross purposes almost at all times and need to be consolidated under a directly elected Mayor.

Thirdly, the mindset (M) of the citizens needs to be more development oriented. Finally, we need to ensure a more rational policy (P) in terms of housing and a sustainable environment,” said Sanjay Ubale, secretary, special projects, government of Maharashtra at the Osaka round table conference.