UP to 6,000 people in more than a dozen villages downstream of the Bengoh Dam are in danger if a breach were to occur, said local PKR leader Willie Monggin as he urged the state authorities to reveal the emergency response plan (ERP) in such an event.

After an emergency motion to debate the dam’s safety was rejected in the Sarawak assembly last month, Monggin, who is Puncak Borneo PKR chairman, today warned that the villages could be “washed away in a river tsunami” should the dam’s retaining wall break.

Among the villages at risk is the Bidayuh village of Bengoh, home to about 700 people, 2.2km from the dam

Monggin said the environmental impact assessment (EIA) of the dam, which also included a risk assessment report in the event of a dam failure, estimated that in such a situation, the Kampung Bengoh villagers had “15 to 20 minutes” to flee, provided they were given warning.

However, the state public utilities ministry did not have an ERP in place, Monggin said at a press conference today. 

Monggin said the EIA report, which was not available to the public, stated that in the event of a dam break, the first area of impact was the Sungai Semadang bridge on the confluence of Sungai Semadang and Sungai Bengoh, and it would be hit in 10 minutes.

“The bridge and the house besides the river at the bridge would probably be washed away due to the force of the water,” the report stated.

The next impact area is Kampung Bengoh.

“Here the impact would most probably wash away the houses by the side of the river. The area will be hit 15-20 minutes after a dam break,” the report stated.

The report stated that areas along Sungai Sarawak Kiri further downstream of Kampung Bengoh would be affected “at a lower rate” due to the “less hilly topography” and the wider river plain.

There are 13 villages in this area – Kampung Danu, Kampung Puruh Semadang, Kampung Boyan, Kampung Giam, Kampung Git, Kampung Landeh, Kampung Sebu, Kampung Lubok Boyak, Kampung Skunyit, Kampung Pluntan, and Kampung Rembus.

The report stated that the dam water could within an hour of a break reach Kuching city, some 31km distant as the crow flies. The likely impact on Kuching would be floods on both banks of Sungai Sarawak and within the city and surrounding areas.

Monggin said the state government must disclose its ERP to the villagers, more so with Sarawak receiving heavier than normal rainfall at this time of the year.

Monggin had last month discovered water seepage in the dam wall and gone to the press with the news.

It prompted PKR Batu Lintang assemblyman See Chee How to table an emergency motion to debate the safety of the Bengoh dam in the assembly on November 15 but this was rejected by Speaker Amar Mohd Asfia Awang Nassar, who said the state utilities minister had  given his assurance that the dam was safe.

Monggin today said remedial work on the seepage had yet to be carried out as the dam operators had difficulty lowering the water level in the dam.

“The minister (Public Utilities Minister Dr Stephen Rundi Utom) has assured that the dam is safe but that does not mean he does not need to have an ERP in place.

“The Ministry of Public Utilities must reveal the dam ERP to the villagers living upstream and downstream of the dam.”

Monggin claimed the siren warning system promised more than a year ago was yet to be installed.

A dialogue session to brief village headmen late last month did not address the ERP, he added, and the reason given was that the engineers who managed the dam were absent.

The RM310 million dam completed in 2010 is a freshwater reservoir for the Batu Kitang treatment plant, which supplies treated water to Kuching and Kota Samarahan. It has a retention capacity of 144.1 million cubic metres of water. – December 19, 2017.