A Japanese company will use novel technology to build a sewer system under the To Lich river in Vietnam’s capital city, Hanoi. The sewer will be 21 km long, including a 11.4 km section running through the river from Hoang Quoc Viet Street in Cau Giay District to Quang Bridge in Thanh Tri District, which will collect wastewater from residential areas in the city’s crowded urban districts of Tay Ho, Ba Dinh, Dong Da, Cau Giay, Hai Ba Trung, and parts of the outlying rural districts of Thanh Tri and Ha Dong to protect the To Lich River.
A Japanese contractor overseeing implementing this project will employ a tunneling method known as pipe jacking, used for the first time in Hanoi, to allow pipes to be laid 6-19 m under the river’s bed along a 13 km section, with minimal disruption to overground activities.
The project is part of the USD 680 million Yen Xa wastewater treatment system funded by Japanese Official Development Aid (ODA). The project includes the Yen Xa wastewater treatment facility with a processing capacity of 270,000 m3/day, and three underground sewer systems for the Lu River, Ha Dong District and To Lich River. The entire length of the pipelines to be installed in the project 52.6 km, with pipe diameters ranging from 315-2,200 mm.
According to Hanoi’s environment department, the To Lich River was known as the ‘dead river’ due to absence of water exchange with other freshwater sources, while being subjected to up to 150,000 m3 of untreated household wastewater a day. The project, expected to be operational in 2021, hopes to address the pollution in the To Lich River and revive the waterway.
(Source: Vietnam News)