Administration to conduct tunnel feasibility study

Adianto P. Simamora, The Jakarta Post, Jakarta

The Jakarta administration will conduct a feasibility study on a plan to build a 22-kilometer tunnel aimed at resolving chronic water and transportation problems in the capital.

"If everything runs smoothly, the administration can complete the technical design by 2009 and start construction by 2010," Firdaus Ali, a member of the Jakarta Water Supply Regulatory Body told reporters after meeting with Governor Sutiyoso on Tuesday.

According to the project design, the administration will construct two levels of roadway in the tunnel as well as waste water reservoirs.

Waste water will then be processed to become clean water in North Jakarta's Pluit drain, the product of which will meet the water requirements of up to 1.5 million residents.

Above the roadways, the tunnel will be used as a utility duct.

The project was first proposed by the body in February after severe flooding which inundated much of the capital.

In its initial proposal, the Rp 4.37 trillion project was designed to handle repetitive floods in the city with the capacity to entrap 30 million cubic meters of water.

Sutiyoso briefed members of the House of Representatives and the City Council on the project at the time and due to negative responses from legislators the body redesigned the project.

It has been proposed that the 22-kilometer tunnel with a diameter of 12 meters will be constructed 15 meters below the West Flood Canal from Jalan MT Haryono in East Jakarta to Muara Angke in West Jakarta.

"At first we proposed the construction of a deep tunnel intended to cope with annual flood problems. But we have now integrated turnpikes, wastewater management and a water recycling system like those in Singapore and Malaysia into the design," Firdaus said.

The body's head, Achmad Lanti, sought support from members of the Regional Representative Council at a seminar on flood problems.

"The project is a good alternative for Jakarta because there will be no need for land acquisition. We hope councilors can support our idea," he said.

The body said that underground drilling works would be conducted using a global positioning system to avoid disturbances or activity on the surface.

Similar underground reservoirs have already been constructed in big cities such as Chicago, Singapore and Kuala Lumpur.

To materialize this plan, the administration will organize an international seminar on deep tunnels to attract investors to fund the project.

Firdaus said that representatives from the Islamic Development Bank (IDB) and investors from Malaysia would attend the seminar.

"We hope 70 percent of funding for the project will come from private companies," he said.

Jakarta has long experienced floods in the rainy season and droughts in the dry season due to uncontrolled land use which has caused land permeability to be low.

Of the city's average rainfall of two billion cubic meters per year, only 170 million cubic meters of rain becomes groundwater, with a water deficit of 36 million cubic meters per year.

The administration is also under pressure to improve the city's poor transportation system which causes heavy traffic congestion daily.