[Vietnam] Hanoi launches approximately USD 450 million Cau Bay River governance project; five underground wastewater treatment plants to be completed by 2028

Introduction: Hanoi, the capital of Vietnam, launched a batch of key projects in a concentrated manner on 10月10日, among which the Cau Bay River Governance and Pollution Treatment Project involves an investment of approximately USD 4.51亿 (116810亿 Vietnamese dong), implemented under the PPP model (BT contract), with a construction period from 2026 to 2028年. It will build 61 km of sewage collection pipelines, 29 pumping stations and 5 underground wastewater treatment plants, with a total design treatment capacity of 14.2万 m³/day, reaching 18万 m³/day during the rainy season. In the same period, the Nhue River governance project has a preliminary investment of more than USD 29亿, and watershed governance projects such as the Phu Do Wastewater Treatment Plant (9.15万 m³/day) are being advanced simultaneously.

Project Overview: Three Major PPP Projects Reshape Hanoi's Water Environment

To commemorate the 72th anniversary of the liberation of Hanoi, the capital of Vietnam concentrated the commencement and commissioning of a batch of key projects covering transportation, environment, healthcare and other fields on 10月10日, with environmental infrastructure becoming a key investment focus. In terms of water pollution treatment, three major PPP projects constitute the main framework of Hanoi's water environment governance during the "15th Five-Year Plan" period:

• Cau Bay River Governance and Pollution Treatment Project — total investment of approximately USD 4.51亿 (116810亿 Vietnamese dong), implemented by a joint venture between Phu Dien Construction Trading Investment JSC and MIK Group, constructed from 2026 to 2028年, covering sewage collection and treatment in areas including Viet Hung, Phu Loi, Bo De, Long Bien, Gia Lam, Bat Trang and Thuan An, serving a study area of approximately 7751 hectares;
• Nhue River Embankment Restoration and Dredging Project — preliminary total investment of more than USD 29亿 (approximately 75万 billion Vietnamese dong), passing through 19 communes and wards along the route, covering riverbed regulation and dredging, embankment construction and restoration, sewage collection culvert construction and riverside wastewater treatment plant construction;
• S3 Watershed Sewage Collection System and Phu Do Wastewater Treatment Plant — total investment of approximately USD 1.56亿 (40380亿 Vietnamese dong), including approximately 24 km of sewage collection pipelines, 5 pumping stations and a wastewater treatment plant with a design capacity of 9.15万 m³/day, serving the western area of Hanoi.

Technical Highlights: Underground Wastewater Plant + Modified SBR, Effluent Replenishes the River

The engineering scheme of the Cau Bay project is quite noteworthy. The 5 wastewater treatment plants are located in Phuc Dong, An Lac, Ngoc Thuy, Dong Do and Phu Thi watersheds respectively, all adopting an underground layout and applying the modified sequencing batch activated sludge (modified SBR) process, in order to save precious urban land, control the impact of odors on surrounding communities, and accommodate the restoration and recreation of waterfront landscapes. The treated tailwater will be used for safe irrigation and to replenish the Cau Bay River, forming a closed loop of "collection—treatment—reuse—ecological replenishment".

In addition to the main plants and stations, the project also includes riverbed dredging, riverbank reinforcement, sedimentation tanks covering approximately 10 hectares, replenishment systems, pumping stations and more than 14 km of riverside roads. Under rainy season conditions, the system's treatment capacity can be increased to 18万 m³/day to cope with the impact of combined sewer overflows under the tropical monsoon climate.

Market Significance: An Overseas Window Amid Southeast Asia's Wastewater Treatment Gap

Industry observers point out that this round of concentrated investment in Hanoi reflects the overall opportunities in the Southeast Asian wastewater treatment market. Rapid industrialization and urbanization have sharply increased water use and discharge demand from Vietnam's manufacturing sector, while sewage collection and treatment rates still have a considerable gap; Vietnam's regulatory framework is also evolving from "pollution control" to "encouraging resource recycling", compounded by the mandatory ESG water management indicators imposed by international supply chains, creating a sustained demand base for environmental protection enterprises.

For Chinese and international water utilities, this round of Hanoi projects releases three clear signals: first, large project scale and mature models — all three major projects adopt the PPP/BT contract model, with investors mainly being local consortiums, leaving substantial room for subcontracting and cooperation in equipment procurement and specialized technical segments; second, rising demand for underground wastewater plants and advanced treatment processes — the high standards of high-density urban areas for land saving, low odor and effluent reuse will drive the application of technologies such as MBR, high-efficiency sedimentation and smart aeration; third, spillover opportunities in supporting industrial chains — there is demand for imported equipment and technical services in segments such as pumping stations, pipeline networks, online monitoring and Digital Twin operation management.

From a regional market perspective, analysis institutions estimate that the Southeast Asian Reclaimed Water market will reach approximately USD 45亿 by 2026年, with industrial demand accounting for about 62%, and the penetration rate of the MBR + Reverse Osmosis combined process in new projects continues to rise. The upgrading of industrial parks and municipal systems in economies such as Vietnam, Malaysia and Thailand is becoming one of the fastest-growing regional markets for the global water treatment industry.

Conclusion

The 4.51亿 Cau Bay River project is only one component of Hanoi's water environment governance blueprint, yet it sufficiently illustrates that the Southeast Asian wastewater treatment market is shifting from "whether to build" to "how to build better." For engineering and equipment enterprises deeply engaged in the wastewater and reclaimed water reuse sectors, closely following the policy rhythms and project rhythms of Vietnam and other Southeast Asian countries will be an important mainline for overseas expansion in the coming years.

About TIANYI TECH: TIANYI LIMITED focuses on the fields of wastewater treatment, reclaimed water reuse, and water environment governance, providing municipal and industrial clients with full-chain services including process design, equipment integration, engineering general contracting, and smart operations. The company continuously tracks global water treatment policies, technologies, and market dynamics, and is committed to helping clients achieve efficient utilization and sustainable management of water resources through reliable solutions. For more information, please visit the company website at www.tianyitech.hk.

Source: Public reports from Vietnamese media including VietnamNet and Vietnam.vn (2026年10月)