The exact page text, read by your browser's voice.
Two arrivals, two different postures — one already inside the county's river, one still held at a gate a hundred miles away: that is the whole shape of the invasive record for this ground, and it prints by animal.
The zebra mussel is in. The Indiana DNR's official list of Indiana zebra mussel waters, updated 12 January 2026, names, for St. Joseph County, one water: the St. Joseph River. The basin science behind the listing was done in this river system: studies of coupled lake-stream systems in the St. Joseph River basin (Indiana–Michigan) in 1993–1995 and again in 2000–2003 found stream colonization driven by infested upstream lakes, adult densities falling from over 1,000 per square metre at a lake outlet to about 10 per square metre within a kilometre downstream — stream populations a sink, fed by lake sources, not self-sustaining marches. The United States Geological Survey's nonindigenous record gives the state's first observation of the species as 1988, the year it was found in Lake Erie. For Lincoln Township the listing's precision is the finding: the county's named zebra-mussel water is its big northern river; neither the Kankakee nor any township water is named on the DNR list reached, and no township record is claimed.
The invasive carp — bighead, silver, black and grass — are not in, and the gate is named and dated. The Kankakee runs from this township's marsh to the Illinois River and the Des Plaines, which the Chicago waterway system connects to Lake Michigan: the same watershed junction, reversed, is a carp road in both directions, and the basin surveys above are the local watch — the 2005 and 2020 Kankakee surveys each record, in terms, that no Asian/invasive carp were collected. The gate itself is the Brandon Road Lock and Dam on the Des Plaines near Joliet, Illinois, identified by the U.S. Army Corps of Engineers as "the critical pinch point" for keeping the carp out of the Great Lakes, where the Brandon Road Interbasin Project layers an electric barrier, underwater sound, an air-bubble curtain and a flushing lock into an engineered channel. Its recent course is part of this section's dated record because the gate's state is this river's state: construction began in 2025 under a Corps–Illinois–Michigan partnership (a $1.15 billion project on the 2026 reporting); the Corps halted work under a stop-work order on 24 July 2026, without public explanation; several hundred juvenile silver carp were then found in the Marseilles Pool, about 80 miles from Lake Michigan — further upstream than routine monitoring had found them since 2010; the order was lifted in early September 2026 and construction resumed. As of November 2026 the gate is building again and the fish are closer than they were. Both halves of that sentence are the record, and neither is softened.
Sources: Indiana DNR, Indiana Zebra Mussel Waters list (updated 12 January 2026); zebra mussel lake-stream studies in the St. Joseph River basin (1993–2003 literature as abstracted); USGS Nonindigenous Aquatic Species profile, Dreissena polymorpha; U.S. Army Corps of Engineers, Brandon Road Interbasin Project pages; Illinois Environmental Council and Alliance for the Great Lakes reporting, August–September 2026 (stop-work, juvenile silver carp, resumption); Kankakee basin surveys 2005/2020 (no invasive carp collected). Closure: DUG at the frames stated — township-level zebra mussel presence is expressly not claimed.