Ecological action protects Xizang salmon industry

Clear water has resumed running through a section of the Yadong River in Dromo county, Xizang autonomous region, while new grass sprouts on land once covered by construction debris — tangible signs of ecological restoration that prosecutors say helped avert risks to a local salmon industry.

The changes followed a public-interest litigation investigation into pollution upstream from salmon farms in local Xiayadong township.

Penpa Norbu, deputy chief procurator of the Dromo County People's Procuratorate, said prosecutors discovered large amounts of food packaging, construction waste and other rubbish scattered and piled along the riverbank while conducting follow-up supervision in connection with Xizang's second round of ecological and environmental protection inspections.

Waste was stacked nearly 1 meter high in some places without protective measures. Temporary toilets at a construction site lacked septic tanks or wastewater collection facilities, allowing domestic sewage to flow directly into the river.

Downstream, sections of the river had turned yellow and turbid and carried a noticeable sewage odor.

The river is the main water source for nearby salmon farms, leaving operators vulnerable to pollution originating upstream.

"The farms could only passively bear the consequences because the pollution sources were beyond their control," Penpa Norbu said.

Farm operators reported that some salmon had died or shown abnormal behavior. They feared greater economic losses if sewage and waste continued entering the river.

Yadong salmon, recognized as a geographical indication product, is one of the border county's best-known specialties and relies heavily on clean, cold plateau water. Wild Yadong salmon, classified as second-class protected aquatic wildlife in Xizang, are found only in a nearly 20-kilometer stretch of mountain streams running from Shangyadong township to Xiayadong township. The local commercial industry, meanwhile, uses legally bred sterile triploid fish.

The farm involved in the case has 20 breeding pools and produces about 200,000 salmon fry annually.

Since its establishment in 2019 through 2025, the local cooperative generated more than 8 million yuan ($1.2 million) in revenue from salmon sales and distributed more than 5 million yuan in dividends to residents.

Across the county, the salmon industry has helped 857 households and more than 2,300 border residents increase their income through employment and related economic activities.

Given the potential threat to both the environment and local livelihoods, prosecutors moved their consultation meeting from an office to the riverbank.

They conducted field inspections, used drones to collect evidence and visited salmon farms before bringing relevant government departments and the construction company together at the site.

Prosecutors presented evidence, clarified the regulatory responsibilities of different parties and coordinated discussions on an immediate remediation plan.

The construction company, responsible for an infrastructure project in the upper reaches of the river and whose proximity to the river caused pollution, was initially reluctant to make changes, Penpa Norbu said. It regarded the waste and sewage as temporary by-products of construction and underestimated the potential impact on salmon farms downstream.

"The main obstacle was not funding or the construction schedule, but weak environmental awareness on the part of the company," he said.

After prosecutors explained the relevant legal responsibilities and potential damage to the public interest, the company agreed to remove the rubbish, improve sewage disposal facilities and strengthen daily management.

However, the remediation process was not entirely smooth.

Because the construction area lacked a regular waste collection system, rubbish would begin accumulating again whenever removal was delayed by a day or two.

Prosecutors therefore carried out unannounced inspections and follow-up visits, urging the company to install garbage bins, build standardized sewage treatment facilities, establish enclosed temporary waste storage areas and introduce a daily collection system, with designated personnel responsible for implementation.

Grass seed was also planted on damaged bare land.

"When we returned, the river was clear again, and what touched us most was seeing new shoots emerging from land that had been damaged by old temporary structures," Penpa Norbu said.

"Vegetation grows extremely slowly on the plateau, so seeing those new shoots was the most direct evidence that the restoration was taking effect."

The case later prompted prosecutors to look beyond the area around the salmon farms.

Dromo county, also known as Yadong county, is an important border area with a frontier stretching about 290 km. As infrastructure projects have advanced, prosecutors have also identified problems including waste dumping, damage to native grassland and unauthorized excavation at some construction sites.

Prosecutors have since worked with multiple government departments to push for corrective measures and urge construction companies to standardize operations, seeking to protect the fragile plateau environment while allowing border infrastructure projects to proceed.

For Penpa Norbu, the salmon case showcased how environmental protection and economic development can reinforce each other.

"Protecting the river also means protecting an important source of income for local people," he said. "In the end, we safeguarded both the environment and their livelihoods."

yangzekun@chinadaily.com.cn