scientist wants upper Yangtze dams scrapped Top fisheries: One of Chongqing Municipality’s major tasks this year is to raise financing from the central government for construction of the Xiaonanhai [Xiaonanhai means small south sea in Chinese] dam project. According to local media reports, the Xiaonanhai dam would cost 23.9 billion yuan RMB [US$3.5 billion] making it the single largest project in Chongqing’s 11th Five Year Plan.
TGP Editors’ Note: The Xiaonanhai dam site on the Yangtze river is at Luohuang Town in Banan District, about 30 kilometres upstream from Chongqing city centre, and 700 kilometres upstream from the Three Gorges dam.
With a proposed Normal Pool Level [reservoir height] of 195 metres, the Xiaonanhai dam would have an installed generating capacity of 1,750 MW, about two-thirds the capacity of the Gezhouba dam [built downstream of the Three Gorges dam] on the Yangtze River. All the power generated from the Xiaonanhai project will be used exclusively within the municipality [population 13 million], where power shortages are still a problem.
The Xiananhai project is part of the “Comprehensive Water Resources Development Plan for the Yangtze River Basin,” which was approved by China’s State Council in 1990. Following Xiananhai, the plan recommends another two dams, Zhuyangxi and Shipeng, for the main channel of the Yangtze between Xiangjiaba and Three Gorges.
The Xiananhai dam would be situated in a nationally designated rare-fish conservation zone on the Jinsha River (as the upper Yangtze is known).
Three Gorges Probe – In 1987, China’s State Council designated a 500-kilometre section of the upper Yangtze as a National Yangtze Rare Fish Conservation Zone. [Click here to view map] Years later, the Three Gorges Corporation, builder of the Three Gorges project, started building a string of dams on the Jinsha River in the area that was set aside for conservation. Two of the four dams, Xiangjiaba and Xiluodu, were completed last year.
Prior to their construction, Chinese environmental groups warned that the four dams (Xiangjiaba, Xiluodu, Wudongde, Baihetan) could wipe out up to 60 fish species whose migration routes to traditional breeding grounds will be blocked. They pointed to China's Environmental Protection Act (Section 3, Article 17), which came into force in December 1989, and states that no industrial enterprises or infrastructure projects likely to cause environmental damage can be built in scenic spots, nature reserves or other special areas designated by the central or provincial governments.
To get around this legal barrier, the Three Gorges Corporation asked the State Council to redraw the boundaries [view map] of the conservation area to exclude the heart of the zone - the stretch of the river between the future Xiluodu and Xiangjiaba dams. The State Council agreed to the request in April 2005, redesignating the protected fish zone to an area downstream of Xiangjiaba, thus clearing the way for the dams to be built. The new reserve zone covers the section of the Yangtze from Yibin downstream to Chongqing, along with the lower reaches of the Min River, and a small section of the Chishui River near where it joins the Yangtze.
Xiaonanhai proponents have argued that since the dam site is in the so-called experimental zone of the upper Yangtze fish reserve, and not its core zone or buffer zone, the Environmental Protection Act need not apply in this case.
Cao Wenxuan, a 75-year old member of the Chinese Academy of Sciences and senior researcher at the Academy’s Wuhan-based Institute of Hydrobiology, disputes this argument. Professor Cao points out that while the dam is in the experimental zone, the backwater of the dam’s reservoir extends to the buffer and core zones, thus posing a serious threat for the area’s rare fish.
Cao Wenxuan is one of China’s top fisheries experts, who has studied fish in the Yangtze River for the last half century. He gets really upset talking about the plight of the fish and the rare fish in particular. There are 119 rare fish species in the Yangtze but their living environment is deteriorating and their survival space has become smaller and smaller, he says since construction of the Gezhouba dam in the 1970s and the Three Gorges dam in the 1990s.
It was Professor Cao who originally advocated for establishing the rare fish conservation zone in the upper Yangtze decades ago. He says under the current circumstances, leaving the reserve zone undisturbed is the only way to protect the rare fish. Certain rare fish species require an uninterrupted migration channel so the eggs they hatch can survive afloat in the current. The population of such species is declining and may even be on the brink of extinction as the reserve zone keeps shrinking, and the channel length available for fish migration becomes shorter and shorter.
Professor Cao told China Youth Daily he’s really concerned not only about the upper Yangtze reserve becoming smaller and smaller due to construction of hydro dams, but also about the river channel (within the reserve zone) becoming fragmented by big dams under construction upstream and smaller dams proposed by local governments downstream. He says “officials know only how to eat the fish but they don’t bother to protect them. This is how the habitat for rare fish in the upper Yangtze has been destroyed bit by bit.”
If Chongqing Municipality goes ahead with the three dams, Xiaonanhai, Zhuyangxi, and Shipeng – their reservoirs stretching for hundreds of kilometres between Xiangjiaba (upstream) and Three Gorges (downstream) – both the core zone and experimental zone of the rare-fish reserve would be flooded, with only a 41.9-kilometre length of buffer zone remaining. [Or less than ten percent of the original rare-fish reserve’s channel length.] As many as 30 locations identified as critical habitat and breeding grounds within the re-designated reserve zone would be seriously affected.
Studies on the environmental impact of building the Xiaonanhai hydro dam have been conducted even though the dam project has not yet officially started. But according to one expert commenting on the project feasibility study at a Ministry of Agriculture press conference last February, the Xiaonanhai report was poorly done and did not explain how the dam’s construction would affect the environment and particularly rare fish. One leading expert attending the press conference was heard angrily repeating three times: “The report is too rough and unprofessional to be accepted.”
The report apparently suggested that a special fish channel be built in the affected zone, in an effort to save the rare fish. But fisheries experts doubt whether that would work without further feasibility studies and scientific experiments. Professor Cao says building such a channel would be an ineffective measure because fish in the upper Yangtze are adapted to and thrive in a rapidly-flowing water environment. The fish would have difficulty adapting to a new and static water environment after the dam [Xiaohanhai] is built. Furthermore, the rapid current along the upper Yangtze would totally disappear if the hydro dams are built. Therefore, building a special fish channel (in the affected zone) is far from a final solution to the problem.
Guo Qiaoyu, project leader of the US-based Nature Conservancy’s Yangtze Program is concerned about the rare fish reserve. For years, she has been working on how to simulate a [fish-friendly] water environment before a cascade of hydro dams are built on the Yangtze River. Like many other experts, she is growing increasingly anxious about the construction of Xiaonanhai because the reserve zone will become more fragmented than ever. If the dam is built, all her efforts and those of her colleagues will be wasted because the habitat for the rare fish would be completely destroyed. Guo says further research and talk of fish protection would be meaningless.
Ma Yi, vice director of the Yangtze Fishery Resources Administrative Committee expressed his concerns about the fish at the second Yangtze Forum held in 2007. He reported that the number of Chinese sturgeon, which is known as a living fossil in the Yangtze, has sharply declined since the construction of the Gezhouba dam [completed in 1988, 44 kilometres downstream from the Three Gorges dam]. Also, the fish fry population for the “four big-named cultivated fish” has dropped at an alarming rate since the Three Gorges reservoir was filled in 2003. Official data indicates a 90 per cent drop in fish fry population between 2004 and 2006, compared to the population before 2003. According to Mr Ma, this is an indication that the environment of the Yangtze river as a whole is getting much worse and it explains why so many people are worried.
Mr Ma further pointed out that while building hydro dams on the Yangtze have important benefits, the dams have also produced a series of tremendously negative impacts on aquatic life: destroying aquatic habitat, blocking fish migratory routes, and flooding or simply destroying fish breeding grounds, all of which has led to the degradation of various species, a huge decline in fish populations, and even unusual changes in the genetic makeup of different species. More importantly, the effect of this entire destructive process may be irreversible: species that cannot adapt to the altered aquatic environment will go extinct, causing a gradual loss of biological diversity in the Yangtze valley.
Many experts have long believed that one of the most significant impacts of building the Three Gorges dam is the loss of aquatic species’ habitat. When a 600-kilometre stretch of the Yangtze was transformed into a [slow-moving] reservoir, lots of fish species accustomed to a fast-moving and relatively shallow water environment were unable to adapt to a more static and deep water environment. When migratory fish species try to migrate, they discover their habitat so seriously disrupted and so small, they no longer have much hospitable living space left. The construction of big hydro dams such as Xiluodu and Xiangjiaba is likely to destroy important breeding grounds for rare fish, which will be another big blow for the fish species already disrupted by the Three Gorge dam project.
To deal with this situation, Professor Cao has made several suggestions: Plans to build more hydro dams on the main channel of the upper Yangtze and its major tributaries should be abandoned, and he says dams already completed or under construction on the upper Yangtze should be removed. “To solve the energy problem, we cannot always keep our eyes only on hydropower. We have to seek alternatives and new energy, such as wind power, solar energy, nuclear power, and so on.”
Weng Lida, a retired expert in water resources protection and former director of the Yangtze Water Resources Protection Bureau, has suggested curbing development of hydropower on the Yangtze, by clearly defining zones that are unsuitable for development or suitable for limited development. Such definitions, along with relevant laws and regulations, should be incorporated into a new comprehensive development plan, he says. By doing this, the big dam projects generating big controversy could be temporarily suspended. Then the green light could be given first to dam projects with the least impact on the environment.
Ma Jun, author of the 2006 book, China’s Water Crisis, has also called for a slow down in the pace of dam building along the Yangtze, and protection of some rapid-moving water environment to reduce the negative effects of hydro dams on aquatic life and prevent the extinction of Yangtze fish.
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