On 28 July, the United Nations Development Programme (UNDP) in Vietnam, working with the Dutch Government, the Institute of Environmental Science and Engineering (IESE) at Hanoi University of Civil Engineering, and DEEP C Industrial Zones, launched a technical guideline for industrial wastewater and sludge reuse under the Accelerating Circular Economy for Businesses (ACE-Biz) project, according to a report published 22 August by Vietnam Economic Times. The guideline is paired with a 1,000 m³/day reuse pilot drawing from a central wastewater treatment plant of about 6,000 m³/day at the Dinh Vu Industrial Park (DEEP C1) in Hai Phong.
Key takeaways
- UNDP Vietnam, the Dutch Government, IESE-HUCE and DEEP C launched the ACE-Biz technical guideline for industrial wastewater and sludge reuse on 28 July, per Vietnam Economic Times.
- The pilot at Dinh Vu IP (DEEP C1) reuses 1,000 m³/day of polished water from a 6,000 m³/day centralised wastewater treatment plant, per Vietnam Economic Times.
- Decision No. 222/QD-TTg of 23 January 2025 targets more than 70% wastewater treatment in river basins by 2030, per Vietnam Economic Times.
- Reuse is currently limited mostly to internal operations inside tenants, with no detailed standards for cross-tenant trade, per Vietnam Economic Times.
- DEEP C's General Director flagged legal complexity and missing technical standards as the main brakes on outside-tenant reuse investment, per Vietnam Economic Times.
What happened: guideline sets reuse rules, pilot shows the path
The guideline structures three reuse scenarios for treated industrial water: cooling-tower make-up, irrigation and road washing, or higher-grade polishing for production and partial domestic use, Vietnam Economic Times reported. Each pathway is evaluated for technical requirements, financial efficiency, environmental benefit, and health and safety, supported by a health-risk assessment that runs from technology selection through distribution network management.
The legal framing sits on three pillars, all cited by Vietnam Economic Times: the Law on Environmental Protection 2020, the amended Law on Water Resources 2023 — which encourages water reuse and offers incentives for water-saving investment — and the National Action Plan on Circular Economy to 2035 under Decision No. 222/QD-TTg dated 23 January 2025, which targets more than 70% wastewater treatment in river basins by 2030 and lists IPs, industrial clusters and concentrated production zones among priority sectors.
On the ground, a pilot at Dinh Vu IP (DEEP C1) in Hai Phong pulls a side-stream from a centralised wastewater treatment plant of about 6,000 m³/day and polishes 1,000 m³/day for re-supply inside the park, per Vietnam Economic Times. The reported effect is reduced freshwater abstraction and better use of existing treatment assets.
What operators and buyers said
Professor Nguyen Viet Anh, Director of IESE at Hanoi University of Civil Engineering, told Vietnam Economic Times that reuse is shifting from a fragmented internal activity to a strategic water-security choice, but adoption is still "early and uneven". Mr. Bruno Jaspaert, General Director of DEEP C Industrial Zones, told the same outlet that complex legal rules, missing technical standards for recycled water, tax policy gaps and the need to prevent cross-contamination with regular clean water are the open issues. Ms. Diep Thi Kim Hoan, Chief Sustainability Officer at DEEP C, told Vietnam Economic Times that inter-tenant transfers raise new questions on water-source classification, party responsibilities and permit amendments, and that tenants want regulators and international partners to help refine the Dinh Vu model so it can be replicated.
Specification read: what a 1,000 m³/day reuse side-stream means for a plant engineer
The Dinh Vu scheme is a tertiary polishing and reuse side-stream, not a greenfield plant. The reported 1,000 m³/day of reused water is roughly 17% of the 6,000 m³/day coming out of the central wastewater treatment plant (arithmetic from figures reported by Vietnam Economic Times), or about 1.0 MLD — equivalent to the wastewater output of a town of roughly 6,000–10,000 inhabitants on a 150–200 L per capita per day basis (general industry range, not from the sources).
A reuse project of this class sits on the end of a standard industrial wastewater train: screening and grit removal → primary clarification (often Air Dust Treatment for the ventilation side) → biological treatment such as A2O, MBBR, SBR or UASB, with MBR membranes increasingly used where discharge limits are tight → tertiary polishing (sand/UF/RO depending on target quality) → disinfection before reuse. The Dinh Vu pilot bears specifically on the tertiary-and-disinfection stage and on the distribution network that links the polishers to in-park cooling, irrigation, road-wash and, in the higher-grade scenario, production users. Sludge handling, a parallel constraint, will determine whether reuse actually delivers a circular-economy win, and the package the guideline covers under the ACE-Biz project is broader than water alone: it explicitly bundles in sludge handling and reuse, so procurement teams should evaluate Sludge Treatment options alongside the polishing train, and benchmark against Mbr Membrane Systems where the reused stream feeds cooling or process water with tight conductivity and silica limits. The reader-facing guide DAF vs Clarifier for Chemicals Wastewater in Coushatta, US: 2026 Factory Selection Guide is a useful counterpoint for the primary-clarification step upstream of this kind of reuse train.
If your park or plant sits in the 5,000–20,000 m³/day range, treats mixed industrial effluent, already meets BOD/COD discharge limits and is now being asked to cut freshwater intake, this event matters because it is the first documented Vietnamese template for moving from internal reuse to structured, audited, cross-tenant reuse inside an IP — and it comes with a guideline you can hand to your design consultant and your environmental regulator in the same meeting.
FAQ
What did UNDP Vietnam actually launch in July 2026?
A technical guideline for industrial wastewater and sludge reuse under the ACE-Biz project, built with IESE-HUCE, the Dutch Government and DEEP C, per Vietnam Economic Times. It covers technology selection, risk management and post-treatment water-quality control for IPs.
How big is the Dinh Vu reuse pilot and what does it cost to replicate?
Reported at 1,000 m³/day of polished water drawn from a 6,000 m³/day central WWTP, per Vietnam Economic Times. The guideline does not report a capex figure. Tertiary polishing with UF/RO for an industrial reuse skid of roughly 0.5–2.0 MLD typically sits in the low single-digit USD per cubic metre of daily capacity range (general industry range, not from the sources); site-specific cost depends on feed quality and target reuse class.
Which treatment stages does this event bear on for a buyer?
Primarily the tertiary polishing and disinfection stage at the back end of an existing wastewater train, plus the reuse distribution network and sludge handling. Buyers should evaluate Mbr Membrane Systems and Sludge Treatment options against their influent profile.
What is the next step for tenants who want to trade treated water inside an IP?
Per Vietnam Economic Times, tenants and IP operators are still waiting on detailed technical standards, tax treatment, water-allocation rules and cross-contamination safeguards before inter-tenant trade can scale. Expect the Dinh Vu pilot to feed into national-level guidance under Decision 222/QD-TTg.
