Environmental Management Administration

In earlier times, the Erren River's downstream section was known as Erchenghang or Erzhanhang River. By the 1980s, the area became a hub for scrap metal recycling and refining factories. Initially centered in the Wanli area of Tainan City, the industry gradually expanded to neighboring regions such as Rende Township (originally in Tainan County) and Qieding and Hunei Townships (originally in Kaohsiung County). Scrap metal processing predominantly relied on open-air burning and crude acid-washing methods. While these techniques extracted valuable metals from scrap, open-air burning generated air pollution, and untreated wastewater from chemical agents was discharged directly into the Erren River. Large quantities of waste byproducts were also dumped along the riverbanks, leading to severe environmental degradation.

On Aug. 22, 1987, the Environmental Protection Bureau of the Department of Health, Executive Yuan, was upgraded to the Environmental Protection Administration, Executive Yuan. By 1989, the import of scrap metals was banned and in 1993, all scrap metal parallel imports were banned. To combat illegal smelting operations, the EPA (now the Ministry of Environment) established the Erren River Illegal Smelting Pollution Remediation Task Force on Sept. 27, 2000. On Oct. 2, the Erren River was included in the "Taiwan Rivers and Oceans Management Plan," and a patrol team was formed. In 2002, the entire 65.2-kilometer length was severely polluted. After decades of efforts, by 2024, the severely polluted length was 14.8 kilometers, decreasing to 22.6%. Additionally, the Sixth River Management Branch of the Water Resources Agency, Minstry of Economic Affairs, along with the Tainan and Kaohsiung city governments, has removed over 180,000 tons of industrial waste from several disposal sites along the riverbanks.

The Sixth River Management Branch of the Water Resources Agency commissioned the "Waste Assessment and Testing Service Plan for Erren River's Estuary to Erchengxing Bridge Section" in 2020, investigating pollution in the middle and lower reaches of the river. Based on the plan, the "Second Phase Implementation Plan for Erren River Waste Cleanup (Draft)" was proposed. The cleanup targeted four key disposal sites, including Under Erren River Bridge (right bank), 450 meters upstream of Nanding Bridge (right bank), sixth to seventh Water Gates (left Bank, opposite Erxing Temple), and 170 meters downstream of Nanding Bridge (left bank).

Water quality analysis based on River Pollution Index (RPI) and heavy metal testing data was conducted at water quality monitoring stations upstream and downstream of waste disposal sites, Erchenghang Bridge and Nanding Bridge, near the Erren River waste disposal sites. The RPI water quality monitoring is conducted monthly, and heavy metal monitoring is conducted quarterly.

• For annual water quality monitoring data, please visit the Ministry of Environment's Environmental Water Quality Information website.

In Sept. 2022, the administration commissioned a professional contractor to implement the "Erren River Waste Disposal Site Environmental Investigation and Cleanup Program Evaluation Plan." Relevant results were submitted to the Water Resources Agency, Ministry of Economic Affairs, for incorporation into the "Second Phase Implementation Plan for Erren River Waste Cleanup (Draft)" as reference for amendments. To verify whether cleanup methods could more efficiently handle waste and its environmental impacts, additional funding was granted in July 2023 to the Tainan City Environmental Protection Bureau for the "Erren River Waste Cleanup Pilot Project," which has been completed.

To thoroughly resolve the risks posed by waste in the Erren River, the Ministry of Environment (MOENV) took responsibility for special subsidies during an Executive Yuan meeting. The Executive Yuan approved the project's budget, with the understanding that this should not be used as a precedent for other programs. On Feb. 4, 2025, the MOENV submitted the "Phase 2 Erren River Waste Removal Plan (Draft)" to the Executive Yuan for review. On July 18, 2025, the Executive Yuan approved the "Phase 2 Erren River Waste Removal Plan," allocating as much as NT$1.36 billion in funding , more than NT$1.3 billion of which will subsidize Tainan City Government's implementation. This significant investment reflects the firm determination of both central and local governments to resolve the Erren River's historical pollution once and for all. Once dubbed "Taiwan's Heilong River" for its severe pollution, the Erren River is now entering a key phase of comprehensive rehabilitation.

For information on the progress of waste disposal site management in the Erren River basin, please visit the Tainan City Environmental Protection Bureau's "Erren River Basin Waste Disposal Site Management Progress" section. A timeline and updates are available for reference.

Through the joint efforts of the administration and local governments, the pollution of Erren River has significantly improved, and the proportion of severely polluted sections has greatly decreased. Future cleanup plans will continue to be implemented, further enhancing the environmental quality of the Erren River basin. The public can access the latest updates and relevant information through the Tainan City Environmental Protection Bureau.