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rban planners are urging the central government and the Jakarta administration to leave behind their old-fashioned ways to counter the capital’s endemic flooding problem and to start looking for eco-friendly solutions.

Elisa Sutanudjaja, an analyst with city planning watchdog the Rujak Center, said on Saturday that channeling floodwater to the sea through a waterway and deep tunnel was an ancient solution to overcoming floods.

“The government and the administration should find a solution to manage and keep the rainwater to meet their citizens’ needs for water during the dry season,” Elisa said.

“The drainage system, including waterways they insist on building, is no different from the solution proposed by the colonial government hundreds of years ago.”

Elisa said the administration should focus on adding more green spaces to absorb rainwater, rather than channel the water all the way to the sea.

“The government should change the concrete water canals into green spaces that can provide the soil the ability to absorb rainwater,” she said, citing the example of Singapore’s Kallang River, a once straight concrete drainage channel that has been restored into a natural river.

“The city is always swamped by floods during the rainy season, but faces [clean] water shortages during the dry season. The administration should change their way of thinking.”

Trisakti University urban planner Nirwono Joga echoed Elisa’s sentiments, saying that the city needed an eco-friendly approach to prevent flooding and should avoid polluting the sea with floodwater.

“The government and the administration still see heavy rainfall and floods as a disaster and don’t think about the possibility of managing the water and turning it into drinking water,” he said.

He said that 9.8 percent of the city was currently made up of green spaces, and that the government should increase that percentage to at least 30 percent.

Elisa also debated the administration’s plan to construct a deep tunnel, saying it would not solve the problem because parts of Jakarta’s land mass were around 4 meters below sea level.

“This means the administration is planning to pump the water from the deep tunnel all the way to the ground and then channel it to the sea,” she said, highlighting how inefficient and costly the project would be.

The government and the city administration say they will jointly construct a waterway to connect the Ciliwung River to the East Flood Canal and undertake a massive river dredging project in an effort to allow river water to reach Jakarta’s north coast unimpeded.

Governor Joko “Jokowi” Widodo has ordered the Jakarta Development Planning Board (Bappeda) and the administration’s legal bureau to incorporate plans for the Rp 16 trillion (US$1.65 billion) deep tunnel in drafts of the city’s detailed spatial plan and zoning regulation (RDTR) for 2012 to 2013 and the mid-term regional development plan (RPJMD) for 2013 to 2017.

Despite the skeptics, Jakarta Public Works Agency head Ery Basworo stood by the administration’s plan on waterways and the deep tunnel.

He said it was impossible to turn canal’s concrete embankments into green spaces to absorb river water because it would destabilize the embankments.

However, he said, it was possible to dig percolation pit-like wells along the canals and percolation pits at commercial buildings to maintain the water supply.

“Also, the [deep] tunnel will spare the city from flooding. Water that inundates the ground will be moved to the deep tunnel, and then channeled to the north coast of Jakarta,” Ery said, adding the tunnel would be equipped with a sufficient number of pumps to prevent inundation, with details to follow. (nad)