Vietnam: Ho Chi Minh City Environmental Sanitation Project

Written by The World Bank and Elena Collins on 1 May 2013

The Ho Chi Minh City Environmental Sanitation (Nhieu Loc-Thi Nghe Basin) Project is having a transformational impact on the city, directly benefitting over 1.2 million people with improved sanitation and reduced flooding while at the same time serving as a new city asset that can be enjoyed by the people of Ho Chi Minh City.

Challenge

Development challenges that the project tackled included: An insufficient capital investment to replace decaying infrastructure and to keep pace with rapid urban growth; The frequent flooding that occurred in the city because of undersized drains and inadequate routine maintenance; Severe pollution of water courses, particularly in densely populated areas of cities, because there was no provision for either wastewater collection or treatment and weak utility agencies.

Implementation of the project had also been challenging because:

• The project was technically complex, involving tunneling works which were often subject to unpredictable surface soil and groundwater conditions. 


• The client was unfamiliar with the engineering technology and with bank procurement procedures, repeated changes in the project management, high inflation costs or problematic performance of several contractors.

• The project site was located in the most densely populated central business district of the city with critical traffic management issues.

Solution

For 20 years, Nhieu Loc – Thi Nghe was a dark and smelly canal full of waste. At the start of 2002, the project was designed to address these issues. This involved the construction of a sewer interceptor under the canal, 8 kilometres long and 3 metres in diameter, to improve the canal’s drainage capacity, as well as strengthening of the canal’s embankments and installing over 60 kilometres of sewer lines.

Because the project is located in the central business district, construction work could only be done mostly at night. The unpredictable relocation of existing underground water pipes – including a 2 metre diameter water main, power and telecommunication cables added to the challenge. The project applied tunneling works in Vietnam’s unpredictable sub-surface soil and groundwater conditions that had never been done before.

Nhieu Loc – Thi Nghe Canal

Results

The project had a transformational impact on the city, lifting the city’s urban face.  Thanks to the project, 96,000 households (400,000 people) are now less likely to be impacted by a flood over a 2 year return period and 240,000 households (1.2 million people), now have a centralised wastewater collection. In addition, an analysis of the robustness of the works under thousands of different climate change scenarios indicates that the effectiveness of the drainage system remains resilient againt increased rainfall and sea level rise. However, care will be needed by city authorities when beginning more non-structural measures to reduce flooding and increasing resilience to climate change. There needs to be better urban planning, enforcing restrictions on development in highly vulnerable areas and measures to reduce ground water extraction which is leading to significant subsidence problems in HCMC. 

Between 2002 and 2012, the project included the installation of a 9 km wastewater interceptor with an inside diameter of 2.5-3.0m with a pipe-jacking technology that has been applied for the first time in Vietnam. When the project started it was not a known technology to the engineering establishment in the country. The use of this technology reduced the required resettlement and allowed for works to continue with less impact on the surrounding area. It allowed traffic to be unaffected. This project runs through the city centre in the most congested areas of the city so minimizing such impacts was vital.

The use of technology also replaced and extended 51km of combined primary and secondary sewers and 375km of tertiary sewers. Alongside of this, the team disposed of approximately 1.05 million m3 of sludge and excavated material to increase the hydraulic capacity of the canal whilst strengthening 18km of canal embankments by concrete sheet pipes.

The project is having a major positive impact on real estate in the area with the price of real estate fronting the canal increasing and property owners making improvements to their structures. The canal itself has become a major source of civic pride, and is used for recreation. There have been numerous stories in the local media of fish returning to the canal and with them, fishermen.

Bank Group Contribution

IDA provided initial financing of USD166 million in 2001 for project implementation.  Due to inflation in 2007 and 2008, the project cost increased, and in 2010 IDA provided additional financing of US$90 million to cover for the financing gap.

Partners

The Ho Chi Minh City People’s Committee took strong leadership over the project implementation, and mobilized the necessary resources to complete difficult works. The coordination among the central line ministries, Ho Chi Minh City authorities and the World Bank was also closely managed.

Extensive dialogue was held during the preparation stage with all relevant ministries and city departments. Public consultation was conducted during project preparation, including project beneficiaries and relevant stakeholders. Women’s Union groups assisted with consultations with the Project Affected Families.

The Government of Vietnam and Ho Chi Minh City Authority also ensured counterpart funding of US$68 million for implementation of the project. 

The private sector was responsible for the design and construction supervision of the project (CDM). The private sector also was responsible for the construction of the work under contract to the city authorities.  The World Bank understand the city is considering a potential PPP for the phase 2 of the project which will be the design, build and operation of a wastewater treatment plant.

Moving Forward

There are many lessons that other cities can learn from this experience but perhaps the most important one is that large engineering projects can provide benefits beyond those anticipated. While this project has the clear benefit of making the city more resilient to flooding and impacts of climate change as well as serving to collect wastewater from over 265,000 households, it has also been transformative in that it serves as a visible marker of a modernizing city. The city is now also working to improve other canals in a similar fashion. The main challenge for the town, however, will be to ensure the proper operation of the works  (sluice gates, a pumping station and combined sewer outfalls) are properly maintained and that solid waste is better managed in the city to avoid the problem of solid waste being improperly disposed of in the city's drainage system. 

Phase II of the project is under preparation. It includes:

i) A wastewater treatment plant

ii) Remaining interceptor

iii) Sewerage in District 2. This will be the natural continuation of the project as it will treat the wastewater that is now being temporarily discharged into the Saigon River. With the preliminary cost estimate of US$478 million, the Board date is expected in Dec. 2013. 

Categories: Engineering, People, Living, Technology, Health