The Marengo River is a cold-water trout Stream with good numbers of native brook trout, and rainbow trout. You will catch an occasional brown trout too. The Friends of the Lincoln Community Forest and the Wild Rivers Chapter of Trout Unlimited encourage catch and release. An enormous flood in 2016 scoured the valley floodplain and washed away overhanging vegetation, making casting much easier. Most of the river is not easily accessible. You’ll fish where few ever have.