Cambodia advanced its decentralized wastewater-treatment policy in Phnom Penh in a report published on 31 October 2026, with national technical guidelines and quality-management standards targeted for development across the country’s wastewater sector. The reporting highlights a treatment gap: about 9 percent of Cambodia’s wastewater receives treatment before discharge Cambodianess.
- About 9 percent of Cambodia’s wastewater receives treatment before discharge, according to the Asian Development Bank Cambodianess.
- Phnom Penh’s Choeung Ek Wastewater Treatment Plant began operating in 2023 and is designed to treat 5,000 cubic meters per day using pre-treated trickling-filter technology Cambodianess.
- Cambodia’s decentralized wastewater cooperation project spans 2026 to 2028 and covers planning, design, construction, operation and maintenance standards Construction & Property News.
- The new standards initiative includes stakeholder consultation, capacity-building training, procedure validation and nationwide dissemination for national and sub-national implementation Construction & Property News.
What happened
The Cambodianess report published on 31 October 2026 described how rapid urbanization, combined sewer systems and limited treatment capacity are placing Cambodia’s wastewater system under strain, with untreated discharges affecting rivers, wetlands, public health and economic activity Cambodianess. It reported that much of Phnom Penh’s wastewater enters the Bassac and Mekong river systems without adequate treatment Cambodianess.
Separately, coverage published on 8 September 2026 said the General Department of Wastewater Treatment Systems under the Ministry of Public Works and Transport and BORDA Cambodia had signed a technical cooperation agreement and launched a workshop on decentralized wastewater guidelines in Phnom Penh Construction & Property News. The agreement was executed on Friday, 28 August 2026 Construction & Property News.
The 2026 to 2028 project is intended to create official national technical references and establish the DEWATS-QMS quality mechanism across the project lifecycle Construction & Property News. Inter-agency teams will review legal, policy and regulatory standards while developing specifications for system planning, technology selection, engineering design, construction, operation and maintenance Construction & Property News.
“Establishing national technical guidelines and a structured DEWATS quality management system represents an essential and timely intervention,” said Kouch Bunlyt, Secretary of State at the Ministry of Public Works and Transport Construction & Property News. The official said standardized benchmarks are needed from planning and design through commissioning, operation and routine maintenance Construction & Property News.
Current operating context includes the Choeung Ek Wastewater Treatment Plant, which began operations in 2023 and is designed for 5,000 cubic meters of wastewater per day Cambodianess. The plant uses pre-treated trickling-filter technology and is intended to improve discharged-water quality, protect public health and support sustainable urban development in Phnom Penh Cambodianess.
Specification Read
The reported Choeung Ek design capacity converts directly to 5,000 m³/day, or 5.0 MLD; it is 0.005 MLD, equivalent to 5,000 cubic meters per day Cambodianess. The source does not provide the plant’s design population equivalent, influent flow split, BOD/COD concentrations or discharge limits, so those procurement inputs cannot be derived from the available evidence. For decentralized systems, the treatment train generally runs from screening and primary solids removal to biological treatment and then tertiary treatment or disinfection where the selected process and receiving-water requirements require it. This standards project bears most directly on process selection, engineering design, commissioning, operation and maintenance rather than on a specified new treatment capacity Construction & Property News.
For a plant that looks like a decentralized wastewater system with flow expressed in m³/day, a defined industrial wastewater profile, measurable BOD/COD loads and tightening compliance expectations, this event means specifications and operating procedures may need to follow Cambodia’s developing national DEWATS references Construction & Property News. Operators can use the Municipal equipment guide to compare treatment configurations, while the Rural Sewage Treatment in Myanmar: 2026 Buyer’s Guide provides additional context for decentralized plant scoping.
FAQ
What capacity was reported for Phnom Penh’s Choeung Ek plant?
The plant is designed to treat 5,000 cubic meters of wastewater per day, or 5.0 MLD, using pre-treated trickling-filter technology Cambodianess. The available report does not give a design population equivalent, average or peak flow split, BOD/COD basis, so a buyer would need those project inputs before comparing plant configurations.
What will Cambodia’s new DEWATS standards cover?
The 2026 to 2028 cooperation project covers system planning, technology selection, engineering design, construction, operation and maintenance Construction & Property News. It also includes standardized tools and protocols, stakeholder consultation, training, procedure validation and dissemination for national and sub-national implementation Construction & Property News.
How should a supplier be selected for a decentralized wastewater project?
The reported standards work will establish specifications for technology selection, design, construction, operation and maintenance Construction & Property News. A procurement process should therefore require bidders to map each proposed treatment stage to those references and demonstrate commissioning and maintenance procedures, although the sources do not report tender price, lead time or award criteria.
What information is still needed to compare treatment costs?
The sources do not report capital cost, operating cost, procurement schedule or unit-price ranges, and they do not provide the plant’s BOD/COD basis or discharge requirements Cambodianess. A comparable budget needs the flow profile, wastewater composition, treatment objectives, site conditions and the applicable technical requirements before suppliers can price the scope Construction & Property News.
