Norway blows up hydro dam to restore river health and fish stocks | Rivers
A dam that has blocked the Tromsa River in Norway for extra than 100 years was blown up with dynamite this week, releasing migratory routes for fish.
“It’s a big step,” stated Tore Solbakken of Norwegian angling club Gudbrandsdal Sportsfiskeforening, who has campaigned for 5 many years to have the previous hydropower plant dam taken off. “I’m extremely content. It’s all about restoring healthier rivers and fish populations.”
Built in 1916, the seven-metre superior dam in the smaller city of Fåvang, in Innlandet, east Norway, has not been in use for a lot more than 50 yrs. The Tromsa is a tributary of the Lågen River, which feeds into Lake Mjøsa, Norway’s major lake. Campaigners say getting rid of the dam will support fish in the spot thrive once again, including grayling, burbot, Alpine bullhead and prevalent minnows. It is hoped the major beneficiary will be the lake-dwelling trout, which can weigh additional than 10kg and feeds in downstream lakes and the Lågen. Till now, the fish have only been ready to stay and spawn in the lower 950 metres ahead of the dam, while they will quickly be equipped to swim 10km upriver.
“A number of several years in the past, I watched the DamNation documentary and that encouraged me to try to take out dams that aren’t in use any more,” reported Solbakken. “Fish barriers, hydropower dams, roadbuilding and the way we protected rivers versus flooding are all massive complications for huge brown trout and other fish. It is significant to choose care of all the modest rivers. If we do that, we can have a positive long term for our area.”
The dam’s destruction is component of a pattern to remove the out of date boundaries that litter Europe’s waterways. In October, the Open Rivers Programme, a €42.5m challenge to supply grants to aid the removing of tiny dams and the restoration of river move across Europe, was launched with the backing of the charitable fund Arcadia. Very last thirty day period, the European Fee produced a guide for member states to establish barriers that could be removed to enable accomplish the aim of restoring 25,000km of rivers to absolutely free-flowing by 2030.
“Dams in rivers block migration routes – the swimways – of fish,” claimed Herman Wanningen, founder of the Environment Fish Migration Foundation and Dam Removing Europe. “Some fish species, these as Atlantic salmon, eels and sturgeon, vacation countless numbers of kilometres to full their lifecycle. Dams also impede crucial sediment and nutrient transportation, and significantly transform the natural move of rivers. Breeding locations are missing.”
It is approximated that there are at least 1.2 million instream limitations in Europe and that they are a issue in the significant drop in the amount of migratory freshwater fish across the continent, with numbers declining by a lot more than 90{aa306df364483ed8c06b6842f2b7c3ab56b70d0f5156cbd2df60de6b4288a84f} in between 1970 and 2016.
“Free-flowing rivers underpin a prosperity of biodiversity,” Wanningen explained. “They also present foodstuff for hundreds of thousands and thousands of people, as these rivers are comprehensive of lifetime and fish. Cost-free-flowing rivers produce rich sediments, which are vital to agriculture and also mitigate the effects of floods and droughts. There’s so a great deal probable for totally free-flowing rivers in Europe.”
“Norway is a big hydropower state. Taking away dams below isn’t usual,” reported Solbakken. “But it is not controversial if you are taking away old dams that are not in use, in rivers secured by regulations versus new hydropower.”
The marketing campaign by Solbakken and the 120 customers of the fishing club resulted in the authorities agreeing to foot the monthly bill of 3.4m kroner (£290,000) to take out the dam.
On Wednesday, the compact group drilled 5 holes deep into the dam then packed 20kg of dynamite into each individual a single. Blowing up dams is uncommon in Europe but was judged to be the safest approach in this scenario. “As prepared, the dam cracked in the center and prime,” claimed Solbakken. “The subsequent stage is to use the excavator. It’s a large dam and it will just take times to eliminate it all. There is still loads of do the job to do.”
The staff will then established about restoring the river specifically ahead of the dam internet site. “The Tromsa dam is in a steep canyon, so our challenge is to create up a character-like stage-pool cascade to permit the fish to swim upstream in the potent current,” mentioned Ulrich Pulg, a fish biologist and river restorations pro. “This venture will have various just one-metre techniques. It will appear like white-drinking water rapids throughout floods but massive lake-dwelling trout will make it.”
Other dams are earmarked for removing throughout Europe in 2022, together with in Spain, France and the British isles. “More and far more river administrators and NGOs are buying up their instruments for excavations,” reported Wanningen. “Just a couple of months ago, three dams in Montenegro and one in Slovakia went down for the first time in the historical past of these nations around the world. The European exploration project, Amber, which we participated in, has shown there are about 150,000 dams and weirs in Europe that have no function any a lot more and can be taken out with out any issue.
“Rivers are the veins of the Earth. We will need to address them with treatment.”
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