Chishui benefits from balanced approach

Editor's note: This year marks the 20th anniversary of President Xi Jinping's proposal of the concept that "lucid waters and lush mountains are invaluable assets". China Daily will present a series of stories on how resources such as mountains, rivers, lakes, forests and farms are being transformed into priceless gifts.

Among dozens of large tributaries of the Yangtze River, the Chishui distinguishes itself as particularly unique. It is the only tributary that has not been dammed along its main course, and serves as a haven for over 160 fish species, playing a crucial role in the biodiversity of the Yangtze basin.

Yet, its ecological significance is paralleled by its economic importance, as its banks are lined with the country's most baijiu distilleries, earning it the nickname "liquor river".

This makes the Chishui a pivotal testing ground for the harmonious integration of development and conservation, embodying the core spirit of the concept of "lucid waters and lush mountains are invaluable assets", proposed by President Xi Jinping two decades ago.

To date, regions along the river have responded admirably to the test. The ecological environment of the Chishui has seen significant improvement, while the local baijiu, or white liquor, industry continues to thrive.

Flowing for over 400 kilometers, the Chishui rises in Southwest China's Yunnan province and joins the Yangtze in Sichuan province, but its longest stretch is in Guizhou.

The section of the Chishui in Guizhou's Renhuai county is one of the areas with the highest concentration of baijiu distilleries.

The production of sauce-aroma baijiu, which necessitates high fermentation temperatures, peaks in summer. Consequently, significantly more wastewater is generated during the hotter months.

In response to the seasonal challenge, the Renhuai government has bolstered its efforts to enhance baijiu wastewater treatment capacity, achieving a notable daily capacity increase of 13,000 metric tons in 2023. An intelligent system has also been introduced to improve wastewater processing management.

According to Lu Jun, an employee at Renhuai Water Affairs Co, the system can show in real time the exact amount of wastewater discharged by baijiu distilleries, the influent and effluent volumes of each of the 12 wastewater treatment plants, as well as data on key water pollution indicators.

The system automatically alerts maintenance personnel to any emerging issues, he said. The design of the network means that the workers can halt the flow of wastewater, and close relevant drainage outlets that discharge into the Chishui to ensure that no untreated water leaks into the river.

"Typically, all wastewater is treated on the same day it is generated to a quality reaching national standards for discharge into the environment," he said.

High concentrations of wastewater and elevated temperatures can, however, diminish the processing capacity of treatment facilities, he said. To address potential risks, storage pools with a total capacity of 40,000 cubic meters were built to accommodate wastewater that cannot be treated immediately.

In 2021, the Renhuai government launched a campaign to phase out or upgrade outdated baijiu production capacity, and merge small distilleries with inadequate pollution control facilities, decreasing the number of baijiu distilleries in the county from 1,925 to 868.

A sewage plant treats urban wastewater in Bijie, Guizhou province, last year. [Photo by Zhou Xunchao/For China Daily]

The campaign addressed the long-standing issue of the county's baijiu industry, where distilleries with inadequate competitiveness operated in a highly scattered and small-scale manner, according to the Renhuai government.

In another move to enhance the conservation of the Chishui, authorities in Guizhou have dismantled most small hydropower stations along the river's tributaries.

At a recent forum in the provincial capital Guiyang, Yi Yun, head of the province's water resources department, said that as of the end of last year, the department had demolished 195 small hydropower stations in the Chishui basin.

For the 29 stations left, measures have been taken to ensure the necessary flows needed by nearby ecosystems, he added.

In 2017, a 10-year fishing moratorium was imposed on the Chishui. As a result, the environmental and ecological conditions in the Chishui basin have significantly improved, and the local baijiu industry has further thrived.

As of the end of last year, all of the 39 tributaries of the Chishui in Maotai township, once heavily polluted partly because of the baijiu industry, had said farewell to water quality of below Grade V, the lowest in the country's five-tier quality system for surface water.

The efforts have resulted in a remarkable recovery of fish resources in the Chishui, according to the agriculture and rural affairs department of Zunyi, a prefecture-level area that oversees Renhuai.

Zhu Zhongsheng, an official with the department, said its monitoring found that there are now 98 species endemic to the Chishui in Zunyi, compared with 90 before 2016.

"The population structure of fish species has also been significantly optimized," he said, adding that the average weight of Onychostoma sima, or Sima shoveljaw carp, for instance, has increased 263 percent.

According to provincial authorities in Guizhou, as the general quality of water improved from Grade II to Grade I from 2013 to 2023, the total output value of the sauce-aroma baijiu industry on the banks of the Chishui jumped from 48 billion yuan to 150 billion yuan ($6.7 billion to $21 billion).

Last year, the Renhuai government reported that the output value and value added of the baijiu industry in the county increased by almost 10.7 percent and 8.1 percent year-on-year, respectively.

Surging success

Hubei province's Yidu county provides another potent example to demonstrate that environmental conservation doesn't need to be in conflict with economic development.

As a response to President Xi's directives to safeguard the Yangtze and curb overdevelopment, the Yidu government's decision to relocate fish farms inland in 2016 has produced two significant outcomes: fostering the sustainable growth of the local sturgeon industry and revitalizing the Qingjiang River, another tributary of the Yangtze.

The sturgeon farming sector in the county took shape during the 1990s. By 2016, this industry had become a cornerstone of the local economy, involving nearly 560 households and accounting for 30 percent of the nation's sturgeon output.

Back then, the farming operations covered an extensive water surface area of roughly 8.65 square kilometers. The heightened utilization of fodder to enhance sturgeon growth resulted in remarkable eutrophication within the Qingjiang, causing water quality in some parts to plummet below Grade V.

Deng Zhongzheng, who had 30 cages of sturgeons in the Qingjiang, was keenly aware of the increasingly polluted situation in the river back then. Fish cages for sturgeon farming covered most of the surface of the watercourse, with only a narrow channel left. "Certain sections of the river appeared black, while some others took on a reddish hue, dotted by a lot of rubbish and dead fish," he recalled.

No longer having to endure the challenges of weather on his floating farm on the Qingjiang, Deng now works at an onshore base known as "sturgeon valley".

Built in 2018, the base covers an area of over 120,000 square meters and accommodates more than a million sturgeon, according to the Yidu government.

Ji Jianyi, general manager of Qingjiang Sturgeon Valley Special Aquaculture Co, said the base is a green and intelligent facility that guarantees "win-win outcomes for ecological improvement and profitability".

Drawing water from the Qingjiang, the base uses an advanced digital platform to precisely regulate water quality, flow rate, temperature and dissolved oxygen levels, effectively replicating the ecological conditions of the watercourse, he said.

The platform, which can be controlled via smartphone, carries out continuous monitoring over every corner of the base's fish farming area, he said.

"Integrating monitoring, detection and control functions, it can accurately manage and automatically carry out operations such as feeding and oxygenation," he said.

Ji highlighted the adoption of a microbiological circulation purification system, which utilizes high-pressure oxygen for the treatment of excrement and sewage. The treated water still needs to undergo multiple purification processes before being discharged back into the Qingjiang.

The application of digital technologies has enhanced the cost-effectiveness of sturgeon farming. This factory-style mode only needs 1 percent of the area needed by the previous floating farms, and water consumption has reduced by 95 percent, said Liu Zhongxing, an executive at the base.

"Both the production capacity and quality of sturgeon roe have seen significant improvements," he said.

In the caviar processing workshop of the sturgeon valley, workers, clad in protective gear, swiftly process the freshly harvested roe. Outside the workshop, refrigerated trucks stand ready to dispatch the latest batch to Shanghai and Shenzhen in Guangdong province.

Such scenes of organized urgency have become routine for workers in the workshop, who send over 10,000 tins of caviar daily to Europe, the United States and the Middle East, as well as domestic metropolises such as Beijing and Shanghai.

This relentless demand has kept sales executive Ma Min extremely busy. "Currently, 150,000 boxes of caviar are awaiting delivery for domestic orders, while we have received multiple urgent requests to fulfill 3 metric tons of international orders," she said, adding that despite a heavily packed production calendar, new orders keep coming in.

Yidu has 24 sturgeon farming enterprises, which produce 10,000 tons of sturgeon and 180 tons of caviar annually.

The county's sturgeon caviar is exported to over 20 countries and regions, fulfilling a third of the global market demand. The annual output value of its sturgeon farming industry has reached nearly 1 billion yuan, according to the Yidu government.

To address the surging demand, the sturgeon valley is expanding its sturgeon farming area and enhancing its caviar processing capacity. Scheduled for completion by the end of September, this expansion will boost its annual caviar output capacity sixfold to 600 tons.

With the quality of water in the Qingjiang consistently at or above Grade II, and the continuous boom of the sturgeon farming industry, the local government has a more ambitious plan. Yidu aims to harness the industry's potential by developing a modern industrial park that combines fish breeding, aquaculture processing and comprehensive multichannel distribution.

"We aim to attract 1 million visitors annually and foster the development of a 10-billion-yuan industry through strategic collaboration across the entire supply chain," it said in a statement.