Sheboygan — Efforts to minimize erosion and stabilize the only Class A trout stream in southern Wisconsin began this week in Sheboygan County.
As many as six sites along the Onion River are being prepped for the installation of lunker structures, according to a news release attributed to Brownsville-based Michels Corp. The structures will be embedded into the riverbank, covered with layers of limestone and mulch, and ultimately help minimize erosion and stabilize the watershed, according to the statement.
The 100-square-mile watershed has undergone sustained reclamation and restoration efforts since the late-1990s to help trout and other wildlife reinhabit the area. Since the mid-20th century, the river has seen its natural trout populations nearly vanish. Headwater alterations caused the narrow, cold stream to grow wider and warmer. Those factors, combined with nearby agricultural practices that led to pollution and contamination, have made it almost impossible for trout to inhabit the river.
In the late-90s, the Lakeshore Chapter of Trout Unlimited and other environmental groups, with the support of businessman Terry Kohler and the Sheboygan County Land and Water Department, began buying area around the Onion River to allow restoration efforts. Those efforts were aided by a restoration plan developed by the DNR.
Although trout in the Onion River have started to make a comeback, population levels still only are about 10 per 100 feet of stream – well below the original levels before environmental changes.