Strategic dam placement can steadiness hydropower and fish preservation – TechnoNews

Hydropower crops needn’t be disastrous for fishermen and nature. For that, we have to place new dams extra strategically, but additionally modify and even take away some current ones. Valerio Barbarossa and Rafael Schmitt confirmed that with a pc mannequin of the Asian Mekong basin.

A battle between the sustainable growth objectives of reasonably priced and clear power on one hand and life under water, and no poverty and starvation on the opposite is starkly evident in and across the Mekong. This river originates in Tibet and flows into the South China Sea after 4,900 kilometers. Barbarossa explains, “This river basin hosts one of the most productive freshwater fisheries on Earth. It is home to more than 1,000 fish species, and this fish forms the primary income for many families.”

Over the previous thirty years, the fish and fisherfolks within the Mekong Basin have more and more confronted issues on account of massive dams for hydropower era. “These have been placed ad hoc, without considering the consequences for fish and the livelihoods of many depending on them,” says Barbarossa.

Optimum hydropower with fish preservation

Producing the identical and even barely extra hydropower with out all these unintended effects is feasible. Barbarossa from the Leiden Institute of Environmental Sciences and Rafael Schmitt from Stanford College in California explored easy methods to optimally arrange hydropower era whereas preserving fish populations. They revealed their work on June 12 in One Earth.

The 2 researchers created a pc mannequin of the decrease Mekong Basin, that means that the half occupied by China is excluded. The mannequin initially assumed a state of affairs with out dams and looked for an optimum distribution of dams throughout the Mekong’s total river basin.

Optimum for the mannequin meant most hydropower era and minimal influence on fish populations. Thus, the mannequin positioned dams by minimizing the cascading results that boundaries have on fish habitats. The mannequin additionally retrofitted dams with, as an illustration, fish ladders the place doable.

A bypass permits megafauna to swim previous the dam

“Fish ladders are not an optimal solution for many fish,” Barbossa explains. “They usually target fish like salmon with specific swimming characteristics.” Different options, like nature-like bypasses, might additional enhance the longitudinal connectivity greater than ladders, permitting extra fish species to go across the barrier.

“Particularly some of the basin’s ‘megafauna’ like the Giant Mekong catfish that can reach three meters in length and weigh up to 350 kg. However, these fish passage solutions only work for relatively small dams, lower than 50 meters, so they should not be seen as a silver bullet,” he emphasizes.

The researchers in contrast the perfect situation with one which carefully resembled the present distribution of dams. They outlined three situations for policymakers: with low, medium, and excessive ambition ranges.

On the lowest ambition degree, all current dams stay, solely future dams are strategically positioned for optimum hydropower and fish populations. On the medium ambition degree, the eight dams with the best influence on fish and fewer than fifty meters excessive are enhanced with fish passages. This permits some fish to partially migrate upstream or downstream once more. From this place to begin, the pc mannequin proposed different new, strategic dams with fish passages.

Eradicating dams brings in regards to the highest advantages

Within the highest ambition situation, ten dams are eliminated and changed with dams in several areas. This brings in regards to the highest advantages for fish and complete hydropower revenues. It could appear unlikely to occur, however it’s already occurring within the EU and the US. Schmitt. The researchers say, “Every year, thousands of, often obsolete dams are removed. Just have a look at the website damremoval.eu.”

The 2 scientists performed their analysis with the Mekong River Fee in thoughts. Barbarossa explains, “All Mekong countries except China work together within this international commission to generate—preferably sustainable—hydropower for the Mekong region. If policies to protect freshwater biodiversity in such an international basin are possible, this commission could facilitate them.”

Extra hydropower is predicted

The researchers imagine their mannequin can also be related to different elements of the world. “It has been projected that by 2050, there might be 70 % more hydropower than now,” they write.

“Especially along the tropical belts, hosting high fish diversity and highly productive freshwater ecosystems, hydropower is booming. The Amazon region is a clear example of this.” With Barbarossa and Schmitt’s technique, policymakers can use hydropower whereas minimizing hurt to fish populations and the individuals who rely on them.