Such road engineering technique also saves on travelling time and fuel due to distances being shortened, besides preserving the environment as water catchments and biodiversity will no longer be disturbed as normally happens during road construction.
Stating this when officiating at the "Hole Through" ceremony for Sepanggar Port Tunnels costing RM60 million - the first such in the State - near Sapangar Bay Port Terminal, Tuesday, Chief Minister Datuk Seri Musa Aman said although the initial costs are high, it is cheaper in the long run when maintenance is factored in.
If accepted, Musa, who is also State Finance Minister, said road tunnel construction would become a reality in connecting Tamparuli and Ranau, Penampang and Tambunan as well as Beaufort-Keningau-Tenom.
Besides convenience for people plying these routes, several hundred million ringgit would be saved on road and slope repairs, particularly along landslide-prone roads such as along Tamparuli-Ranau and Penampang-Tambunan.
"This proposal can be given consideration because it is for the convenience of the rakyat," he said, adding this also shows that the Barisan Nasional (BN) State Government cares and is attentive to the needs of the people.
Deputy Chief Minister-cum-Infrastructure Development Minister Tan Sri Joseph Pairin Kitingan, who was also present, had earlier suggested to Musa that such road tunnel technology be considered for routes in highland areas throughout the State.
The Sepanggar Port Tunnels - a twin two-way tunnel each 600 metres by 450 metres long that connects the port and Universiti Institut Teknologi Mara (UiTM) - is 73 per cent complete and expected to be opened to public on April 15, next year. It reduces travelling distance by seven kilometres compared to the normal route. Musa said the project implemented by the State Infrastructure Development Ministry and Public Works Department (PWD) is very meaningful because it is the first road tunnel created in Sabah.
"This shows that the State PWD, with assistance from Federal PWD, can make a success of whatever project is entrusted to themÉthis also proves that the State BN Government always listened to the grouses and needs of people, including the business community," he said.
Musa was also pleased to note that green technology was used in making the tunnels. "It is something we can be proud of because the tunnels not only provide convenience but also helps conserve the environment."
State PWD Director Datuk John Anthony said the cost of major repairs on main roads in Sabah is around RM250 million per 5-Year Plan or RM50m a year since the Eighth Malaysia Plan (8MP). He said slope repairs for the Tamparuli-Ranau road alone cost about RM110m per 5-Year Plan or RM22m a year and yet there are many more problem slopes along the road yet to be repaired or mitigated.
"Most highland areas in Sabah are covered with forest which are very rich in biodiversity. Highlands also form the headwaters of most rivers that flow into the State.
The Crocker Range, which is geologically set from the north to the south of the State, is the toughest terrain in so far as road construction is concerned. Most of the weak slopes occurred at weak soil or weak geological formation where the road traverses," he said.
"Capitalising on the use of eco-friendly technology such tunnelling techniques, construction of viaducts and canopies at problem stretches would minimise landslide problems, besides avoiding massive earthwork which would affect the biodiversity of the highland," he added.