6 September 2018
Mr.TepsakTitaraksa, Assistant Governor of the Metropolitan Electricity Authority (MEA), recently presided over the launch of the Chidlom outgoing tunnel excavation, which, with a diameter of 3.6 metres, will be the largest power transmission tunnel in Thailand. The project is being undertaken to ensure that power transmission is adequate and sufficiently secure, and to improve the attractiveness of the city of Bangkok in preparation for its designation as a “Smart Metro” Asean metropolis. The launch ceremony was held at the head office of the Metropolitan Electricity Authority,Ploenchit Road.
The Assistant Governor revealed that the project is an important aspect of plans for the future power distribution system since it will facilitate the development of high-voltage underground cables to cover more urban areas. The project will promote expansion of the MEA’s existing underground power lineswhich currently connect to the Bangkapi and Chidlom terminal power transmission stations using 230-kV cables. This latest project will extend the system from Chidlom Road to Sarasin Road (beneath the road system) and Ploenchit Road (betweenChidlomand Ploenchit Intersections). The tunnel will be 3.6 meters in diameter at a depth ofaround 40 meters and approximately 1,300 meters in length, making it the largest power transmission tunnel in Thailand. The existing tunnelbetween Bangkapi and Chidlom has a diameter of 2.6 metres. Excavation of the tunnel will employ a Shielded Tunneling technique using 2.6- and 3.6-metre-diameter drilling rigs, which can be used to excavate the tunnel while simultaneously erecting the tunnel walls. The system is also able to set a curved tunneling path.
In terms of safety, the tunnel is equipped with advanced technologies including a drainage pump system for use in the event of flooding, freeboard tunneling of 1.20 metres height, a fire alarm system and a ventilation system to help prevent fires. The total construction cost is Bt878 million with a construction period of 1,080 days (2017 – 2020).
The project will answer the growing demand for electricity in central business districts of the city that are experiencing continuing growth. It will also improve the reliability of the power transmission system and reduce the risk of physical damage to conventional above-ground power lines as a result of accidents and storms. It will also support projects in the vicinity that are replacing overhead cables with underground ones as well as connect to the conduit built by MEA with the electric rail line on Ploenchit Road. The integrated development will continue to bring cost-effective returns on investment.
The overall 230-kV underground power transmission project is divided into four parts including those that have been completed, comprising the tunnel project between the Bang Kapi and Chidlomterminal power transmission stations covering a distance of 7 km and the Lad Phrao – Vibhavadi power transmission tunnel, and those currently under construction, including the Prakanong Canal project and the outgoing tunnel at Chidlomterminal station.
For each underground construction project, MEA implements traffic management plans together with the relevant local agencies such as the administrations of Bangkok, Nonthaburi and SamutPrakan, and the National Police. The plans help manage the closure of any areas and speed up operations to ensure rapid completion and minimal impact to the local people. The MEA has prepared a public relations plan to inform the public about progress being made on the project throughout the period of implementation. There will also be staff on the ground to offer information and advice to people in the area prior to and during the construction phase. If you have any questions, please contact the MEA Call Center at 1130 24 hours a day.