New bridge restores

a trout stream’s natural flow

Replacing a narrow culvert that restricted the Platte River, a blue ribbon trout stream in northern Michigan, restored the river’s natural flow and reduced stream bank erosion that was suffocating prime spawning areas for trout and salmon. The bridge that replaced the culvert also increased public safety by providing a safe road over the river.


The Burnt Mill road crossing, located near the headwaters of the 90-mile-long Platte River, featured a culvert that restricted the river’s natural flow. Water that backed up behind the culvert caused stream-bank erosion, which caused trees to fall into the river and unleashed sediment that buried rocky spawning areas favored by trout and salmon. The river’s altered flow increased water temperatures, which threatened the trout population. Replacing the undersized culvert with a wooden bridge restored the river’s natural flow, the natural movement of sediments and aquatic life, and provided a safer river crossing for motorists.

Resource Challenges Addressed

  • Altered river flow
  • Excessive sedimentation
  • Suffocated fish spawning habitat
  • Unnatural warming of water temperatures in the river


A bridge crosses a small creek.

The new Burnt Mill Bridge restored the Platte River’s natural flow. Credit: Conservation Resource Alliance.

Results and Accomplishments

Restored the river’s natural flow, which will help the native brook trout population; reduced the volume of sediment washing into the river by 5 tons annually; and restored the natural movement of nutrients and aquatic life above and below the road crossing.