KONJIC (Thomson Reuters Foundation) - Plans to build about 3,000 hydropower plants in the Balkans in the next few years endanger Europe’s last wild rivers and some of the most important biodiversity hotspots on the continent, campaigers said on Saturday.

Stretching from Slovenia to Albania, critics say the hydropower boom threatens animal life, including endemic species of fish, and people’s access to water used for drinking, fishing and farming.

“There is a tsunami of hydropower dam constructions happening here and nobody really knows about it,” said Britton Caillouette, director of “Blue Heart”, a documentary that focuses on efforts to halt the hydropower plans.

“Blue Heart”, which had its world premiere on Saturday in a screening at the Idbar dam near Konjik, focuses on local people’s and campaigners’ efforts to halt the plans.

Investment in renewable energy projects is growing around the world as countries rush to meet clean energy goals under the Paris Agreement on climate change.

The EU aims to source at least 27 percent of the bloc’s energy from renewables by 2030.

Western Balkan countries, including Bosnia, Kosovo, Montenegro and Serbia, plan to invest billions of euros in building new coal-fired plants to meet rising demand for electricity as old plants are being phased out.

Hydropower is already widely used across the region but environmentalists fear the investment in coal could backfire as governments may be forced to invest hundreds of millions of euros more to upgrade plants to meet European Union environmental standards as the countries progress toward membership of the bloc.

The European Bank for Reconstruction and Development (EBRD) is funding some hydropower projects in the Balkans and has agreed to foster a transition towards sustainable, low-carbon economies in the region.

Ulrich Eichelmann, head of campaign group RiverWatch, said clean energy such as hydropower, could have negative effects on the environment.

“Just because it doesn’t emit CO2 it doesn’t mean it’s good,” Eichelmann told the Thomson Reuters Foundation.

The small-scale nature of most of the projects in the Balkans is particularly damaging because water is diverted through pipelines, leaving empty channels where rivers used to be and causing loss of fauna and erosion, a 2017 report by consultancy Fluvius said.

The report said more than a third of the planned dams are to be built in protected areas, including some in national parks.

“With the deluge of proposed hydropower dams and diversions in the Balkan peninsula we are looking at what could be irreversible environmental destruction, but there is very little awareness of this issue in Europe or globally,” said Ryan Gellert, general manager, EMEA, of outdoor clothing company Patagonia, which backed the film financially.

The U.S. company has been backing environmental causes for a long time and recently joined a lawsuit challenging plans by the Trump administration to alter national monuments, federal land that is protected from development.