Lake Trösken has two major inflows, the Älengssån river is a natural inflow and the Dalälven river is connected via a tube.
The threshing floor is a lime-rich water that has greatly improved water quality as all households have been connected to municipal sewage. The swamp flows out into the sea via a stream in Harnäs, and BillerudKorsnäs has a pumping station.
Part of the Trösken is part of Natura 2000, as both the lake and parts of the surroundings are worth preserving. The threshing floor has a rich natural life with several protected species of different insects and birds. Every year, a lot of large perch, pike, tuna and roach are caught, but there are many more species.
There are many nice places to sail from land and there are also several places to launch boats on, the best is at the club's clubhouse where we have a proper ramp with parking for cars with trailer. The lake is also a good place to paddle in and there are many islands to camp on.
The association conducts competitions in the form of pimple, meteor and pike competitions.
In 1946, 23 gentlemen from the area met to form Tröskens Fiskevårdsförening upa with a seat in Furuvik.
The statutes of the association § 1, "The association, whose area of activity includes Lake Trösken in Gävle and Älvkarleby municipalities, has the purpose of achieving improved return on fishing and against illegal fishing in its area."
Today the association conducts competition fishing in the form of meteor, pimple and pike fishing. The association intends to open a creek in Harnäs, which means that migratory fish, including trout and pike, emerge from the sea to Lake Trösken.Customer number: 1167, Area: 1129.