HCMC has no place for 3 million cubic meters of sludge dredged from giant canal

In August, construction workers were advancing on the Tham Luong–Ben Cat–Nuoc Len canal project, with many embankments, sidewalks, and roads nearing completion. However, a significant challenge emerged as vast amounts of sludge remained trapped within the canal, awaiting proper disposal. According to Nguyen Van Cuong, chief supervisor of the construction package, the team had only managed to extract soil from the canal's banks, transporting it to nearby disposal sites.

The sludge in the canal bed posed a formidable obstacle due to the lack of a designated disposal location. The project, spanning more than eight kilometers from Truong Dai Bridge to the Saigon River, encompassed some of the widest stretches of the canal, with areas reaching up to 100 meters in width and containing enormous volumes of sludge, estimated at around 1.7 million cubic meters.

This substantial sludge mountain was contributing to the project's delays, as over 65% of the work had been completed, but dredging activities were stalled due to the disposal issues. The project, launched in February 2023 with an initial budget of VND8.2 trillion (US$312 million), has since seen an increase in costs to more than VND9 trillion after additional components were incorporated.

The canal, one of HCMC's longest, stretches through seven former districts, including 12, Binh Tan, Tan Phu, Tan Binh, Go Vap, Binh Thanh, and Binh Chanh. It is part of a larger project comprising 10 packages that include dredging, concrete embankments, two roads, drainage culverts, boat docks, bridges, lighting, landscaping, and other facilities.

The dredging process aimed to deepen the canal to four to five meters, enhancing drainage and facilitating waterway transportation. However, the sludge disposal predicament threatened the project's timeline. The HCMC Urban Infrastructure Construction Investment Project Management Board, the project's manager, forecasted a total of 4.7 million cubic meters of soil and sludge excavation, with 1.4 million cubic meters of soil slated for on-site filling or transported to nearby disposal sites.

This would leave 3.3 million cubic meters of sludge to be dealt with. Initially, the plan was to transport the sludge to Go Vap Cultural Park and Sub-area 3 in Binh Tan District; but both locations faced opposition due to rapid urbanization and concerns over pollution. Moreover, changes to regulations made the original plan unfeasible as Go Vap Cultural Park was no longer available to receive the sludge, and the city only had two centralized waste treatment sites, Da Phuoc and Tay Bac, for contaminated sludge.

To circumvent the issue, the project managers are now exploring the recovery of Group IV minerals from the sludge, with the city auctioning off more than three million cubic meters of sludge. The winning bidder would be responsible for dredging, transporting, and treating the sludge. The HCMC Institute of Resources Economics and Environment endorsed this approach, emphasizing the necessity of adequate sites for sludge storage and treatment in urban areas.