The installation has approximately 71.2 miles of streams and tributaries within two major basins, the La Crosse and Black River. The delicate headwaters of these two rivers originate within or adjacent to the fort s boundaries. The surface water quality of McCoy s lakes and streams is very good, with approximately 70 percent of the streams rated as Class I trout waters. Thirty species of fish inhabit Fort McCoy waters. These include brook, brown and rainbow trout, as well as largemouth bass, bluegill, crappie and bullhead.
Most streams have native populations of brook trout.
Fort McCoy has stocked fish in lakes and streams since 1963. Historically the Fisheries Program stocked fish to enhance stream trout populations that had limited fish reproduction and at areas that received high fishing pressure. Fort McCoy stocks rainbow trout annually in five to six lakes or ponds. May. The average size of trout stocked is eight inches. The sale of Fort McCoy Fishing Permits is the sole source of funding for the stocking program.