River Habitat Restoration

Leads to 38-fold Increase in Trout Population

Reducing riverbank erosion and placing fallen trees in the Coldwater River restored fish habitat and led to a 38-fold increase in the site’s trout population.


The Coldwater River is one of the largest and highest quality cold water streams in southwest Michigan. The 34-mile-long trout stream is home to 32 species of fish, including brown, rainbow and brook trout. However, riverbank erosion and the lack of fallen trees over the river that would provide prime habitat for fish have left stretches of the river with low fish populations. One such area is a 2,500 foot stretch of the river adjacent to Schrems West Michigan Chapter of Trout Unlimited’s Dolan Property. The river has been dredged, is straight and shallow, and contains little woody debris or other cover for fish—resulting in limited and unfriendly aquatic habitat for trout. In 2010, 38 trees were harvested from the Dolan Property and positioned in the Coldwater River to create fish habitat at 31 locations along the nearly half-mile stretch of river. The log structures have remained in place since construction and have greatly increased the site’s trout population.

Resource Challenges Addressed

  • Lack of native habitat
  • Limited ecosystem diversity
  • No cover for fish populations
  • Poor fish migration


A trout from Coldwater Creek, Michigan, caught in a net.

A trout caught in the Coldwater River. Submerged trees in the river have improved the trout’s habitat substantially with a 38-fold increase in the number of trout spotted between 2009 and 2014. Photo courtesy of Aaron Snell.

Results and Accomplishments

The trout population, according to a July 2014 fish survey, has increased tremendously — from 40 per mile at the Dolan Property in 2009, to 1,523 per mile. The project exceeded its goal of 800 fish per mile by 2013. The survey also found an increase in fish species diversity in the river. The habitat improvement work has remained in place, as documented by annual post-project monitoring.

An excavator places a log into Coldwater Creek, Michigan.

An excavator places a log into the Coldwater River. These logs change the flow of the water in the river, providing hiding spaces for fish and other invertebrates needed for a healthy ecosystem. Photo courtesy of Aaron Snell.

Submerged logs in Coldwater Creek, Michigan.

Submerged logs in the Coldwater River provide habitat for trout and will increase the health of the river overall. Photo courtesy of Aaron Snell.