Where there was once a free-flowing river, now there are piles of rubble, broken pipes and a concrete wall blocking the water.
“Where there was once a free-flowing river, home to a population of Danube salmon, now there are piles of rubble, broken pipes and a concrete wall blocking in the water.”
So explains a news article on the BBC. It isn’t describing some apocalyptic scenario but rather the after-effects of a new hydroelectric dam in Bosnia. The Medna Dam on the River Sana has wreaked havoc with local wildlife and water sources, according to environmentalists.
“We were here a couple of years ago, and the water was over the rocks,” Rok Rozman, a biologist and former Olympic rower from Slovenia who opposes the country’s dam projects, told the British news service. “Western companies are coming here because they can’t do new dams in, say, Germany and Norway. They dammed everything — and there’s legislation to keep them away from those rivers. They know they can pull it off here, where there’s no media attention or legislation like in the European Union.”
Over the past few years hydropower constructions have been mushrooming across the Balkans. Hundreds of new dams, mostly small so-called mini-dams, have been built, are being built or are in the plans in an area stretching from Slovenia all the way to Greece. More than a third of them are set to be constructed in protected nature-rich areas, including national parks and European Union-designated Natura 2000 sites.
Hydropower is the largest source of renewable electricity on the planet. Dams store river water so that when the water is released it can power turbines to generate electricity. The dams are sources of low-carbon energy, which is good. What isn’t so good is that they often bring environmental chaos in their wake. By altering a stream’s or river’s natural flow, they disrupt or interfere with the migrations of animals like fish. Dams also contribute to the buildup of sediments. Their harmful effects can extend for hundreds of kilometers downstream.
Not surprisingly, environmentalists across the Balkans are concerned that the fragile ecosystems of local mountain streams are at risk from the mushrooming of dams in the region. “They divert water through pipelines away from the river and leave behind empty channels where rivers had been,” Ulrich Eichelmann, director of RiverWatch, told The Guardian. “It is a catastrophe for local people and for the environment. For many species of fish and insects like dragonflies and stoneflies, it is the end.”
He elucidated: “This is not renewable or green. Using just three water mills on the river would be good; that would help the locals. But they wanted to do it their way and not consult the locals. We can’t remove the dam – but we want to use this as an example to raise awareness in other places in Bosnia, so they can’t do it there.”
Mere hyperbole? Hardly.
Hydropower dams, if built injudiciously, can inflict severe harm on local ecosystems by subverting the natural flow of streams and rivers. They can also be sources of cataclysmic destruction, as locals in a remote, rural area of Laos learned to their cost last July when a dam collapsed. Dozens, or possibly hundreds of people, died while thousands of others were flooded out of their homes.
Experts have warned that several other dams in the country, which boasts 50-plus dams with dozens more on the way, may yet face a similar fate owing to shoddy construction.
Therein lies a potential problem with hydropower. It’s a steady and reliable low-carbon power source that generates electricity without emitting greenhouse gases. But it can cause grave harm to the environment and local communities by affecting wildlife habitats, worsening water quality, and diminishing the recreational benefits of rivers.
According to a new study by a researcher at the University of California, Berkley, in the United States, addressing potential negative environmental fallouts from hydropower dams must be a priority, even if they come at an economic cost.
“Reducing hydropower generation in order to restore natural river conditions is often considered too costly by hydropower operators, but those costs might be lessened by taking advantage of complex electricity markets and providing grid-regulating ancillary services, especially in regions with high penetrations of renewable energy like wind and solar,” noted the study’s author, Joseph Rand, of the Energy and Resources Group at the university.
“At the same time, environmental groups arguing for more natural river flows must consider the carbon-emissions cost of reduced hydropower being replaced with fossil fuel generation. Yet, these and other important aspects are typically overlooked in hydropower relicensing negotiations,” he cautioned.
In other words, embracing hydropower at an ever larger scale will need to be a fine balancing act between the need for low-carbon energy and the need to preserve local environments.