SkyscraperCity banner
1 - 3 of 3 Posts

·
Moderator
Joined
·
121,773 Posts
Discussion Starter · #1 ·
Island in for a boring few years
24 April 2009
South China Morning Post



The government announced details yesterday about the planned drainage tunnel that will run from Tai Hang to Cyberport, which it says will divert a third of the runoff from a downpour and reduce flooding along northern Hong Kong Island.

Director of Drainage Services Peter Lau Ka-keung said the HK$300 million project, which is expected to be completed in 2012, was necessary to keep pace with the changing geography of the city.

"The existing drainage network in the low-lying urban areas was built decades ago and is no longer sufficient to cope with the rapid urban development since then," Mr Lau said. "But any construction work on the [existing] drainage network would cause serious disturbances to residents and road users."

The new system comprises 34 intake points spaced out along an 11km line that hugs the hillsides from Tai Hang through to Wan Chai, Central, Sai Wan and Cyberport.

The intake points will be built about halfway up the hillsides, with shafts dropping the water into the tunnel.

The rainwater will then flow through the tunnel to a discharge point at Pok Fu Lam.

Mr Lau said the areas would only see serious flooding when downpours exceeded 130mm per hour. Hong Kong gets about two black rainstorm warnings a year, where a downpour exceeds 70mm an hour.

However, Mr Lau said the drainage tunnel could not entirely solve the problems in frequently flood-hit spots such as Happy Valley and Sheung Wan.

In a separate project, an underground storm-water storage tank will be built in the centre of the Happy Valley racecourse to alleviate flooding in the lowlands of Wan Chai south. No date was given for its construction.

In another project in Sheung Wan, four high-powered electric pumps went into operation last month to discharge rainwater into the harbour, Mr Lau said.

He said a rain-interception tunnel was a new and a more feasible method to reduce flooding in the lowlands than the existing system.

He said two tunnel-boring machines with diameters of 7.2 and 8.3 metres respectively, the largest rock-tunnelling machines in Hong Kong, would conduct the drilling from both ends of the tunnel around the clock concurrently. The construction work would cause only minimal disturbance to residents, he said.
 
1 - 3 of 3 Posts
Top