Developing the Lok Ma Chau Loop could cost taxpayers a great deal more than previous public statements have shown, a local think tank predicts.

Civic Exchange says the higher costs arise from the high and growing risk of floods throughout the entire loop area. The organization released a flood risk study for Hong Kong and the greater Pearl River Delta Tuesday, citing historical figures showing that heavy rainfall and rising sea levels have nearly doubled the incidence of flooding in the area over the past century.

The organization urged city planners to re-think development plans for low-lying areas as a result.

The frequency of major flooding caused by typhoons and sewer backwash such as the inundation of Tai O Town Center September 2009 will increase, according to the report's author, Faith Chan, who said the time between extreme rainfall events has been halved over the past hundred years. Incidence of rainfall in excess of 200 millimeters over a three-hour span was approximately once every 41 years in 1900. A century later, the incidence of heavy rainfall was approximately once every 21 years. The study was based on data from the Hong Kong Observatory.

Urbanization north of the Shenzhen River also eroded natural safeguards to floods, magnifying the destructive force of a major event, he said.

The government announced last week that the Lok Ma Chau Loop, the undeveloped 870,000-square-meter lump of toxic mud left over after the straightening of the river, will be developed as a hub of higher learning.

With infrastructure costs projected at roughly HK$10 billion alone to make the loop accessible, Chan believes the entire plan should be shelved, on grounds that costs for the project could balloon as remedial flood measures are required.

While the Drainage Services Department has spent roughly HK$20 billion on remedial drainage projects over the last decade, a better and cheaper way of safeguarding lives, homes and businesses was preventative planning, Chan said.

Although the government has conducted flood risk assessments for the entire city, flood risk ratings have yet to be made public, a necessary step that needs to be taken to protect the lives and livelihoods of citizens, Chan said.

But the likelihood of such a disclosure was slim, think tank Chief Executive Officer Christine Loh said, adding political interests such as impacts on land values meant disclosure was unlikely.

Although the precise flood risk assessments for neighborhoods may not be disclosed, doing so would allow the development of flood insurance locally, which would help transfer some of the burden of recovery from the government, Chan said.

In the meantime, city managers on either side of the border can do their part, he said, urging working groups in both governments to cooperate on flood management.

The Department of Drainage Service (DSD) responded to the survey, saying the assessment of flood risk, based on the 2008 Review of Drainage Master Plan in Yuen Long and North District, was still ongoing and would be completed next year.

The DSD statement continued, that the department would examine the Civic Exchange report and would be prepared to undertake further flood risk studies in the future.

China Daily

(HK Edition 12/01/2010 page1)