Taipei City flood-diversion plan defended

Taipei City yesterday defended a flood-diversion project for the Huangkan River, which flows into Keelung River, saying that dredging alone could not prevent flooding.

Funding for the project has been the main sticking point at an extraordinary session of the legislature called this week to discuss a special budget for flood-prevention measures along the 86km Keelung River.

On Monday, Lee Ying-yuan (李應元), the DDP's Taipei mayoral candidate, criticized the project as a scheme to "spend big bucks, cut big trees and then turn the river's fresh water into a pile of dead water."

In response to the criticism, the city's Bureau of Public Works said it had little choice.

"Because we are restricted by the depth of the river, the only way to prevent flooding in this area is through flood diversion," said bureau chief Chen Wei-jan (陳威仁).

According to the bureau, the flood diversion project consists of constructing underground channels to divert water from the river when it floods.

While inspecting the Huangkan River in Peitou with hydraulics experts, Lee said that the flood-diversion project would damage the environment because it required demolishing the area's parks.

He said the city government should instead dredge the river bed of the Huangkan River to increase its capacity.

Chen said that Lee's criticism was a result of his lack of understanding about such matters.

"Flood prevention is a professional issue," Chen said. "Everyone should avoid politicizing it and take a professional perspective."

The flow of the Keelung River and the shallowness of the Huangkan River meant that dredging would result in backflow, where water would flow from the main river back into its tributary, Chen said.

"To dredge the river's bed is not a good flood-prevention solution [for this river]."

According to the bureau, of the NT$1.98 billion dredging subsidy requested by Taipei City Mayor Ma Ying-jeou (馬英九) from the central government, NT$1.34 billion is for the flood-diversion project and the construction of levees along the Huangkan River.

The remainder is for the Neikou River (內溝溪), another tributary of the Keelung River, and the area near the Chungshan Bridge (中山橋), which is prone to flooding during typhoons.