[Mainland China] HJ 945.4-2026 "Technical Guideline for Formulating Water Pollutant Discharge Standards for Centralized Wastewater Treatment Facilities in Industrial Parks" takes effect on September 1, providing a unified technical framework for the formu

The Ministry of Ecology and Environment approved and released the national ecological environment standard Technical Guideline for Formulation of Water Pollutant Discharge Standards for Centralized Wastewater Treatment Facilities in Industrial Parks (HJ 945.4-2026), effective from 2026年9月1日. This standard is a first release, providing a unified methodological framework for local authorities to formulate and revise water pollutant discharge standards for centralized wastewater treatment facilities in industrial parks. It serves as the supporting standard document to the previous risk prevention notice on industrial wastewater issued by eight departments, directly affecting the wastewater control logic of thousands of industrial parks nationwide.

Core Content of the Standard: Full-Process Regulation Across Five Segments

HJ 945.4-2026 is formulated to implement the Ecological and Environmental Code of the People's Republic of China, prevent pollution, and improve ecological and environmental quality, aiming to guide and regulate the formulation and revision of water pollutant discharge standards for centralized wastewater treatment facilities in industrial parks. The main body of the standard systematically stipulates the full process of formulating park wastewater discharge standards, with core content including:

• Basic principles and technical route — clarifying that standard formulation must follow the principles of scientific rigor, standardization, and feasibility, unifying the technical route and working procedures to avoid inconsistent formulation approaches across regions;
• Formulation needs and classification — based on differences in park industrial structure, wastewater quality characteristics, and receiving water body functions, defining the needs identification and classification/grading methods for standard formulation;
• Determination of key technical content — standardizing the determination methods for key technical segments such as pollutant item screening, discharge limit determination, and monitoring requirements, guiding local authorities to set control indicators tailored to local conditions;
• Benefit and feasibility analysis — requiring systematic demonstration of the environmental benefits, economic costs, and technical achievability of standard implementation, ensuring the standard is "implementable upon release";
• Text structure and compilation instructions — unifying the standard text format and the required depth of content in compilation instructions, enhancing the standardization and reviewability of standard documents.

Policy Context: Implementation of the Supporting Standard to the Eight-Department Notice

2026年8月, the Ministry of Ecology and Environment, jointly with eight departments including the Ministry of Industry and Information Technology, the Ministry of Public Security, the Ministry of Natural Resources, the Ministry of Water Resources, the Ministry of Agriculture and Rural Affairs, the Supreme People's Court, and the Supreme People's Procuratorate, issued the Notice on Further Strengthening Risk Prevention of Industrial Wastewater Pollution to Ensure the Safety of Agricultural Irrigation Water (Huan Ban Shui Ti [2026] No. 13), which explicitly states: where characteristic pollutants discharged by industrial enterprises, such as total salinity, heavy metals, and toxic and hazardous pollutants, may affect the safety of downstream agricultural irrigation water, local water pollutant discharge standards shall be formulated or revised to strengthen discharge control. The Ministry of Ecology and Environment confirmed in its press Q&A that "the Technical Guideline for Formulation of Water Pollutant Discharge Standards for Centralized Wastewater Treatment Facilities in Industrial Parks has recently been issued as a supporting document, guiding local authorities to formulate park water pollutant discharge standards tailored to local conditions."

This signifies that a policy chain of "regulatory requirements — technical guideline — local standards" has taken shape, from the regulatory framework of the eight-department notice, to the technical methodology of HJ 945.4-2026, to the upcoming formulation and revision of park discharge standards across regions. After the guideline takes effect on 9月1日, local ecological environment authorities will have a basis for formulating park wastewater discharge standards, and a concentrated wave of local park wastewater standard formulation and revision is expected.

Industry Impact: From "Compliant Discharge" to "Precision Control + Deep Reuse"

For the industrial park wastewater treatment industry, the signaling significance of this guideline deserves close attention:

• "One Park, One Policy" will move toward standardization — park discharge standards formulated by local authorities based on the guideline will set characteristic pollutant indicators aligned with the park's leading industries, pushing centralized wastewater treatment facilities from "general-purpose compliance" toward "industry-adapted advanced treatment";
• High-standard effluent creates conditions for reclaimed water reuse — with stricter control of characteristic pollutants, advanced treatment processes become a necessity, while improved effluent quality directly lowers the water quality threshold for park reclaimed water reuse, forming a positive cycle of "upgrading standards — reuse";
• Market space for local standards opens up — the formulation and revision of discharge standards across provinces and parks involves water quality criteria research, treatment process demonstration, and techno-economic assessment, bringing a new round of business opportunities for professional water treatment technical service institutions.

Significance for Us: TIANYI TECH's Perspective

TIANYI TECH has long served industrial park wastewater treatment and reclaimed water reuse. We note that after the guideline takes effect, the core challenge facing park clients will shift from "whether compliance can be achieved" to "how to achieve cascaded water utilization and cost optimization on the basis of compliance." This aligns closely with our long-advocated design philosophy of "quality-based water supply and cascaded utilization": the more precise the control of characteristic pollutants, the greater the need for customized advanced treatment and reuse solutions to match. We recommend that park clients conduct early baseline assessments of influent/effluent water quality characteristics and treatment facility suitability evaluations, take the initiative during the new round of local standard formulation and revision, and convert the pressure of standard upgrades into efficiency gains from water resource recycling.

About TIANYI TECH (TIANYI LIMITED): TIANYI TECH specializes in wastewater treatment and reclaimed water reuse, committed to providing efficient, low-carbon, and sustainable water treatment solutions for municipal and industrial clients.

Sources: Standards publication page on the official website of the Ministry of Ecology and Environment (MEE), Q&A session by the Department of Water Ecology and Environment of the MEE, and the "Notice on Further Strengthening Pollution Risk Prevention for Industrial and Other Wastewater to Ensure the Safety of Agricultural Irrigation Water" (Huan Ban Shui Ti [2026] No. 13) and other public materials. This article is a compilation of industry information for readers' reference.