Boulders and loose earth a likely problem when La Nina hits

PETALING JAYA: Granite boulders half-buried in hillslopes along roads around the country and slippery, loose earth at the slopes could prove to be a major problem with the onset of La Nina, which is likely to bring heavy rains.

On Penang island, the Public Works Department is facing a major headache.

Engineers have pulled out many loose boulders along Jalan Tun Sardon, a road that climbs the Penang Hill range from Paya Terubong to Balik Pulau and Bayan Lepas, said state department director Salleh Awang.

“The challenge is that many of the boulders farther uphill are on private land.

“The earthwork necessary to extract the boulders could damage the terrain or even the durian trees up there.

“We have told some of the landowners to keep an eye on landslide risks during wet weather,” he said.

An avalanche of granite boulders along the road on May 28 almost killed passing motorists while a boulder – estimated at 20 tonnes and as tall as a man – crushed the left side of a car, trapping the vehicle.

Close brush with death: An avalanche of granite boulders at this spot in Penang on May 28 nearly killed passing motorists.
Close brush with death: An avalanche of granite boulders at this spot in Penang on May 28 nearly killed passing motorists. 

Salleh said his engineers had investigated the rockslide and found that it was a natural incident caused by heavy rain loosening the soil that had lost its protective plant growth during the drought earlier this year.

Slope experts conducted an inspection of Penang’s roads on June 7 and warned of landslide and water hazards along Jalan Teluk Bahang between Balik Pulau and Batu Ferringhi.

“Around the sharp bends on this stretch, water will gather during exceptionally heavy rain. Cars need to go slow there.

“We have sent men to clear all the drains and make sure rainwater runs off smoothly but the steep slopes and fallen foliage can clog the drains quickly in a storm,” Salleh said.

Around the country, PWD has identified 2,576 dangerous slopes on a map of landslide-prone sites along federal roads.

Of the number, 992 have been tagged as the most dangerous and required strengthening jobs, said Works Minister Datuk Seri Fadillah Yusof said.

Besides Penang, the slopes are located in Cameron Highlands, Lojing, Hulu Terengganu, Hulu Perak, Ampang (Selangor), Ipoh, Kuala Lumpur, Kundasang and Sandakan in Sabah, as well as Kapit and Miri in Sarawak.

To monitor and repair dangerous slopes, JKR has been carrying out surveys across federal roads, excluding tolled highways.

“However, there are still many high-risk slopes elsewhere,” Fadil­lah said.

It would cost billions to repair and strengthen all the dangerous slopes, he added.

“We are implementing the slope-strengthening programme in phases according to priority and availability of funds,” he said.

The budget for JKR is only to secure the safety of slopes along federal roads.

“For roads under the purview of states and local councils, the cost is borne by the state government while JKR provides technical assistance.”

Fadillah said the Inter-Agency Slope Management committee comprising the Urban Well-being, Housing and Local Government Ministry, Mineral and Geosciences Department, Meteorology Depart­ment, highway concessionaires and local governments, among others, was formed five years ago.

Apart from local councils, he said landowners should also bear responsibility in securing the safety of slopes.

Related stories:

Humidity a threat to landslide areas

Slopes on highways deemed safe

Special squads all set to ensure water flows freely

Transport & Safety , granite , boulder , landslide


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