Nhieu Loc-Thi Nghe wastewater treatment plant

The project involves the design, construction, operation and maintenance over 5 years of phase 1 of a wastewater treatment plant. With a peak capacity of 34,000 cubic metres per hour, the pumping station includes biological treatment, disinfection, sludge treatment, odour treatment, and a connection to the city’s sewage system. The plant will provide wastewater treatment services for some 1.4 million people in the Nhieu Loc-Thi Nghe basin and a portion of District 2 of Ho Chi Minh City.

Context

The project is part of a sanitation infrastructure development programme financed by the World Bank, covering the north (Nhieu Loc-Thi Nghe) and east (District 2) of Ho Chi Minh City. It involves building a new wastewater treatment plant on the left bank of the Saigon River to complement an existing equivalent-capacity plant on the right bank.
Our Moving Bed Biofilm Reactor (MBBR) technical solution, whose application in numerous projects was a guarantee of security for the client for a plant of this scale, makes it possible to build a much more compact plant, reducing the footprint outlined in the client’s design by 60%. Furthermore, the technique is well suited to the characteristics of the effluent to be treated, a key feature of which is that it is highly dilute with a low load and high flow depending on the season.

Technical background

Since the plant is located on marshy land, the project will require 15 months of preliminary works. These involve diverting a river which crosses the site, building breakwaters and backfilling.
The plant comprises a pumping station for the wastewater, supplied by gravity at a depth of 20 m. It also covers pretreatment (bar screening, grit removal and de-oiling), biological treatment, clarification, filtration and UV disinfection. The amassed sludge is digested and dewatered. The recovery of biogas produced by the digestion process and the installation of around 15,000 m² of solar panels will help power the plant, with an output of 3.5 MW.

“What makes this an exceptional project is not only its size but the fact that its scope is so comprehensive, both in terms of quality of treatment and energy recovery”, Julien Rayssiguier, director of water works sector

Impact

By treating the wastewater collected in the Nhieu Loc-Thi Nghe basin, the plant will be an essential part of the second Ho Chi Minh City environmental sanitation project and will benefit more than one million people. The project will involve up to 800 local workers at peak periods. Moreover, some 25,000 hours of training are planned to ensure everyone’s safety on site as well as the structure’s quality. This will mean, over time, that local teams can be trained in water works trades, an asset for the future.
This new contract bolsters VINCI Construction’s presence in Vietnam, where its subsidiaries VINCI Construction Grands Projets and Bessac (Soletanche Freyssinet) are currently carrying out a design-build project for a 10-km treated-water transfer pipeline that will supply drinking water to central Ho Chi Minh City.
VINCI Construction Grands Projets has supported Vietnam in numerous sanitation projects in the cities of Thai Nguyen and Hoi An in 2016, Vung Tau in 2013, and Ha Dong in 2008.

Project participants

Client
Ho Chi Minh City People’s Committee

Consultant
Royal Haskoning DHV / DOHWA

Key figures

Dates
January 2020 to December 2024

Fill: 600,000 m3

Breakwaters: 3,800 m

Concrete: 42,000 m³

Installed capacity: 5 MW