Ensuring environmental sanitation during the dredging of Tho Quang Fishing Wharf

By DA NANG Today / DA NANG Today
March 25, 2022, 17:40 [GMT+7]

The preparatory works for the dredging of the Tho Quang Fishing Wharf in Son Tra District, Da Nang, is underway. Since early March, three barges, dredgers and excavators have moved into the wharf in preparation for the dredging work.

Barges and dredgers have gathered at the Tho Quang Fishing Wharf in preparation for the dredging of the wharf and the dumping of the dredged material at sea. Photo: HOANG HIEP
Barges and dredgers have gathered at the Tho Quang Fishing Wharf in preparation for the dredging of the wharf and the dumping of the dredged material at sea. Photo: HOANG HIEP

According to the Da Nang Management Board of Traffic Construction Investment Projects, the investor of a project to enhance the capacity of the Tho Quang Fishing Wharf in providing more space for fishing boats to avoid storms, a total area of 50.17ha at the wharf will be dredged.

The dredging work is expected to start in April 2022 and to be completed in October 2022.

Accordingly, construction units will collect waste from land-to-underwater surface of the wharf, and then shovel it on garbage trucks to transport it to the Lien Chieu District-based Khanh Son Landfill for treatment. During the process of trash collection, biological products will be sprayed to treat odours.

The dredging work will be carried out according to designed subdivisions. An area of ​​3.27 ha inside the talus roof of the wharf (from the bottom of the embankment to the top of the wharf's shore) will have mug and garbage dredged, with an average dredging depth of 1.29m.

Before dredging, the construction units will process probiotics on the surface of the water for 5 days and drop the probiotics in the wharf to ensure the environmental sanitation.

With regard to the dredging method, dredgers will pump mud, sand and garbage onto barges to settle mud and sand, and then separate water on each compartment. Garbage will be collected into large-sized bags which then will be gathered on specialised vehicles to be transported to the Khanh Son Landfill.

In the process of separating garbage, biological products will be sprayed to treat odours. Mud, clay, and sand which are deposited after removing garbage on the barges will be transported to dumping sites at sea at buoy No. 0, about 19.6km from the wharf.

Three barges, with the capacity of 1,495m3/day each, will be used to transport the dredged material to dumping sites. It is expected that an average of 6 trips/day will be conducted, and the volume of dredged material is expected to be about 3,500m3/day.

The dredged material will be submerged in the form of bottom discharge. Before discharging the bottom, the dredged mud will be checked on the barge, if there is a floating substance, the construction unit will be required to use a suction plate to remove the floating scum. The dredged material after being tested (by sense), if there is no floating substance, dredged material will be submerged.

The Management Board of Da Nang Traffic Construction Investment Projects will be in charge of developing a plan to closely monitor the submergence process, sea water quality, and biodiversity at dredged material submergence area and surrounding areas, as well as of monitoring around the clock the operation of each barge.

The unit is also asked to strictly obey the provisions of the law on construction, land, environmental protection, water resources, marine and island environmental resources in all construction activities; make sure that no harm comes to the environment; and implement approved environmental protection solutions to ensure compliance with environmental standards and regulations so as not to cause pollution.

Director of the Management Board Nguyen Minh Huy said that his unit will dredge the Tho Quang Fishing Wharf in tandem with evaluating the effectiveness of the work and its impact on the environment under the supervision and monitoring by such relevant agencies as the municipal Department of Natural Resources and Environment, the city’s Border Guard, the Da Nang Maritime Administration, the Environmental Police, and the Son Tra District authorities.

Deputy Head of the Management Board of the Tho Quang Fishing Wharf and Port Nguyen Lai informed that his unit will closely coordinate with the project’s investor and the construction units to deploy solutions to ensure that the dredging of the wharf would not affect the operation of the wharf and guarantee environmental sanitation during the dredge.

Reporting by HOANG HIEP – Translating by M.DUNG