[Chinese Mainland] Nanjing Issues the "15th Five-Year Plan" Water Affairs Development Plan: Build and Expand 9 Wastewater Treatment Plants, Raise Urban Reclaimed Water Utilization Rate to 30%

The General Office of the Nanjing Municipal People's Government has officially issued the "Nanjing Municipal "15th Five-Year" Water Affairs Development Plan". The plan proposes implementing pipeline network interconnection and rehabilitation projects in areas such as Chengbei, Chengnan, and Jiangxinzhou, building, renovating, and expanding 4 industrial wastewater treatment plants and 5 domestic sewage treatment plants, and promoting the coverage rate of quality improvement and efficiency enhancement compliance zones for wastewater treatment in built-up areas to reach 90%; at the same time, it specifies that the centralized collection rate of urban domestic sewage shall remain at 95%, the urban reclaimed water utilization rate shall be increased to 30%, and the proportion of national and provincial assessment sections with water quality better than Class III shall remain at 100%. Complementing this, 18 wastewater facility projects citywide are being comprehensively advanced, and 174 water affairs projects are being implemented simultaneously.

The Turning Point from "Whether It Exists" to "Whether It Is Good"

The most noteworthy aspect of the plan is not how much additional treatment capacity is added, but the shift in the focus of the target system. Nanjing's water affairs system has completed a round of scale expansion: a cumulative 295 kilometers of wastewater pipeline network renovation has been completed, the daily treatment capacity of 63 wastewater treatment plants has been increased from less than 300 万 tons to 370 万 tons, and the proportion of 42 national and provincial assessment sections with water quality better than Class III has been maintained at 100% for 7 年 consecutive periods.

With the base already very high, continuing to rely on new construction to drive marginal benefits has limited effect. The plan therefore shifts its focus to three main lines:

• Quality improvement and efficiency enhancement take priority over capacity expansion — "coverage rate of quality improvement and efficiency enhancement compliance zones for wastewater treatment in built-up areas 90%" assesses pipeline network collection efficiency and influent concentration, not the scale of treatment facilities;
• Separate treatment of industrial and domestic sewage — the plan separately lists the construction, renovation, and expansion of 4 industrial wastewater treatment plants, meaning industrial wastewater is no longer simply mixed into the municipal system, but follows a route of separate collection and separate treatment;
• Incorporating reclaimed water into conventional water sources — writing "increasing the urban reclaimed water utilization rate to 30%" into the planning indicators marks the transition of reclaimed water from a supplementary water resource into the conventional allocation sequence.

Three Groups of Noteworthy Signal Reversals

Compared with the logic of water affairs investment over the past decade, there are three obvious reversals in this plan.

• From "emphasizing plants over networks" to "coordinated plant-network management" — in the past, urban water affairs assessments looked at "whether there are plants"; now the assessment focus has shifted to "whether the pipeline network is collecting the sewage". The plan lists pipeline network interconnection and rehabilitation projects in areas such as Chengbei, Chengnan, and Jiangxinzhou, essentially shifting the focus from inside the fence to outside the fence.
• From "compliance discharge" to "commercialization of reclaimed water" — the reclaimed water utilization rate target of 30% means that part of the effluent must have stable users, stable water quality, and stable pricing, rather than merely meeting discharge standards.
• From "single-plant operation" to "system scheduling" — the second channel of the Jiangxinzhou sewage collection system has been completed and put into operation. A plant has changed from a single line to dual channels, and a district has changed from a single plant to system linkage. This is a typical case of stock optimization rather than incremental expansion.

Projects Under Construction: Phase IV of the Chengdong Plant and This Year's Advancement Rhythm

As of this year, 18 wastewater facility projects citywide are being comprehensively advanced, and 174 water affairs projects are being implemented simultaneously. The most representative among them is Phase IV of the Chengdong Wastewater Treatment Plant.

• Phase IV of the Chengdong Plant — treatment capacity is being expanded from 35 万 tons/day to 45 万 tons/day. At present, the biochemical tank area has entered the main construction stage, including rebar tying, and the project has entered the final sprint;
• Jiangxinzhou Second Channel — the second channel of the sewage collection system has been completed and put into operation, providing a redundant channel for cross-river conveyance;
• Upgrading of old facilities such as those in Chengbei — a batch of early-built facilities are simultaneously being upgraded to higher standards, which is a typical case of "stock quality improvement". When the upgrades of a plant, a channel, and a system are superimposed, the city's 1800 kilometers of pipeline network and 63 plants as a whole enter a new stage of quality improvement and efficiency enhancement.

What It Means for the Industry

Nanjing's path has direct reference value for similar cities, especially the three practical recommendations.

• Influent concentration will become a rigid assessment item—Pipeline network defect repair, stormwater-sewage misconnection correction, and low-water-level operation will become the main sources of engineering volume during the "15th Five-Year Plan" period, and the demand for related inspection, trenchless repair, and pipeline network monitoring equipment will rise accordingly.
• Dedicated pipelines and dedicated plants for industrial wastewater will become standard—Separating industrial wastewater from the municipal system not only reduces the risk of shock loading on municipal plants, but also facilitates source tracing and accountability for characteristic pollutants. New industrial parks should reserve conditions for segregated collection and dedicated pipeline conveyance at the planning stage.
• Reclaimed water must be planned in sync with users—The utilization rate of 30% cannot be achieved unilaterally by water plants; it must be planned and constructed in sync with users such as thermal power, steel, electronics, and municipal miscellaneous use, including pipeline networks. It is recommended to establish a user list in advance and configure treatment units according to water quality grades, avoiding cost waste caused by building uniformly to the highest standard.

Our Judgment

TIANYI TECH has long provided wastewater treatment and reclaimed water reuse system solutions for municipal and industrial clients. We believe that the demonstration significance of Nanjing's plan lies in this: it redefines "wastewater treatment" as "a link in the urban water system," and expands the evaluation scale from effluent concentration to collection efficiency, resource recovery rate, and system resilience. For equipment and engineering parties, the boundary of capabilities also changes accordingly—no longer just doing the in-plant process well, but also being able to answer the three questions: "how much was collected by the pipeline network, how much reclaimed water was sold, and how much energy consumption was reduced." We suggest that peers, when engaging with similar city clients, extend the boundary of technical solutions from the plant red line to the user end.

About TIANYI LIMITED: TIANYI TECH is deeply engaged in the fields of wastewater treatment and reclaimed water reuse, and is committed to providing efficient, low-carbon, and sustainable water treatment solutions for municipal and industrial clients.