Cleaner Energy, or a Thriving River?

March 2, 2016
Sw Jk

This is a story from East Asia, but it could be happening—or in some form has already happened—just about anywhere.

We’ve long been changing the shape and character of our rivers, for what always seems at the time like the best of reasons. This article from the most recent issue of Stormwater magazine, for example, looks at the process of daylighting streams—uncovering natural streams that were routed into concrete channels and buried years ago, either for flood control or to create more usable urban space, and that have now exceeded the capacity of their confined spaces.

A much bigger example of change is happening right now on the Mekong River. It begins in China’s Qinghai province as the Lancang River and flows southward through Tibet and the province of Yunnan. It defines the borders between Myanmar and Laos and between parts of Laos and Thailand, passes through Cambodia, and ends in a delta in Vietnam. It carries vast amounts of silt—a productive thing in this case, as the silt carried southward by the Mississippi River once helped create the coastal marshes of Louisiana. It supports agriculture along its route and creates habitat for thousands of plant and animal species, including fully one-quarter of the freshwater fish caught in the world.

Now many of the countries that share the river are building dams to create hydroelectric power—a far cleaner source of energy than the coal-burning plants that much of China relies on now. China has already constructed five dams, is building a huge sixth one, and has plans at least 14 more.

To the south, resource-poor Laos is hoping to make hydropower into a major revenue source by 2025, and to that end is planning to build nine dams on the river. Cambodia and Vietnam, both downstream of these dams, are concerned about the effect they will have on those countries’ riverine habitat and fisheries, even as Cambodia is planning to build a couple dams of its own. The problem, some environmentalists say, is that each government and each dam-building project tends to consider mainly the environmental effects of just that single dam, without stopping to assess the cumulative effect of dozens of them.

And yet, there’s the need for energy to consider, too. The region’s demand for electrical power had doubled since 2005 and is expected to more than double again by 2025. The dams will supply a relatively small portion of that demand, but still will offset some of the need for power from fossil fuels.

This article provides a much more detailed look at the technical and political considerations surrounding the river, including the threat of saltwater intrusion into the Mekong delta as sea levels rise. It also provides interactive maps showing the river’s route and the locations of many of the dams.

About the Author

Janice Kaspersen

Janice Kaspersen is the former editor of Erosion Control and Stormwater magazines.