The Don Sahong dam located in the Siphandone area of Laos’ Champasak province. MRC
The Mekong River Commission (MRC) and its partners introduced new technology to measure if one specific large hydrological project will have significant impact on the Mekong River’s water quality, flow or fish population.
In a press statement on June 9, the intergovernmental organisation said they had installed two new sets of equipment to monitor water level and fish species on June 7 at Don Sahong Dam which is located less than 2km upstream of the Laos-Cambodia border.
The first set of equipment, it said, would monitor water level and quality immediately below the dam and report if anything adversely affects that quality in near real-time. The information is of vital interest to the millions of fishing and farming families who rely on the Mekong.
The second technology is called an acoustic telemetry system, which attaches to some migratory or trans-boundary fish species.
MRC said the hydro dams could disrupt the tranquillity of the fish habitat, and construction companies working on dams are now routinely expected to install an elaborate “fish passage” as part of their project to allow the fish to be hoisted upriver and downstream where they typically spawn. However, it has not yet been proven that the fish passage at the Don Sahong dam works as intended.
“This new tagging system will provide that evidence, as it tracks fish movements up and downstream of a few fish passages or fish-ways, including the Hou Sadam and Hou Xangpheuk channels, which the developer has modified,” it said.
Anoulak Kittikhoun, CEO of the MRC Secretariat, said effective policies require accurate data and it was important for the MRC to understand if and how the dam affects water flow and quality and if the fish passage works.
“Then, if needed, we’ll propose appropriate measures for the dam to adjust its operations,” he was quoted as saying in the statement. “The findings and recommendations can also be made for similar dams, so they can build one that doesn’t just generate electricity, but also functions harmoniously with people’s livelihoods – through fisheries resources and other river ecosystems.”
Since the 1985 inception of the Water Quality Monitoring Network (WQMN), the MRC was technologically limited to only measuring the water quality manually, on a monthly basis. That data was then submitted only at year’s end with no warnings about sudden changes in water quality.
“It’s important for all of us to understand the correlation between changes in water level and water quality as quickly as possible,” says Chanthanet Boualapha, Lao vice-minister of natural resources and environment. “This station is in a technically advantageous location to monitor this, as well as being cost-effective, because both types of equipment fit into one housing. The location is accessible year-round, which makes it easy for relevant agencies to maintain it.”
According MRC, there are more than 40 million people who are actively involved in riverine fisheries economically but the catch rates is in decline.
