Deforestation and insularization in central China, where the Three Gorges Dam is situated, has brought native plants and animals to the brink of extinction. The dam has flooded some habitats, reduced water flow in others, and altered weather patterns – leading to the decrease of many species.
One of the most notable effects of the Three Gorges Dam is a precipitous decline in four commercially important carp species (Gangling, Grass Carp, Carp, and Common Carp). The dam altered these fisheries’ migration patterns by controlling Yangtze River flow, consequently, they experienced altered spawning habits.
Due to dam damage, annual harvests of four carp species have declined 50-70% compared to their pre-dam baseline levels. This is particularly concerning for China’s Yangtze fishery – a key source of revenue.
The dam also disrupts the natural flow of the Yangtze River, altering its migratory and spawning patterns as well as maintaining wetlands. This alteration has an immense effect on conservation efforts both within China and downstream states.
Fortunately, measures can be taken to mitigate the negative impacts of the gorges dam. These include reconnecting rivers and lakes, aiding carp spawning, as well as setting ecological operational guidelines for dams.
Some of these measures have been in place for years, but it is essential that the government and its agencies take additional steps to avert environmental disasters.
Davis suggests a holistic, multi-pronged strategy to combat schistosomiasis — a disease spread by snails and spread through water supplies to villagers. Furthermore, Davis notes the government should stop using night soil as fertilizer, build cement irrigation ditches and guarantee that villagers have access to clean drinking water.
Though these steps have been taken, it remains uncertain whether they will be sufficient to prevent an environmental disaster. If not, then the ripple effects of the gorges dam could last for decades to come.
Liu cautions that in the long run, it may be difficult to distinguish the effects of the gorges dam from natural species fluctuations. Therefore, it remains uncertain whether or not the construction of this dam will cause permanent and irreparable harm to plants and animals alike.
To prevent a potential catastrophe, an integrated strategy that considers the wider effects of the gorges dam on both environment and people in the region is necessary. To accomplish this requires collaboration among the Chinese government, conservation groups, other stakeholders as well as scientists.
This case study illustrates how regulations, stakeholder involvement, and science can be utilized to guide the re-operation of an existing major dam to meet expanded management goals. Furthermore, it offers insight into how these processes might influence future dam management in China and beyond.