BOHN PARK

Creek restoration and fish habitat design along the S. St. Vrain Creek
S. St. Vrain Creek restoration image taken from the elevated boardwalk
Universally accessible fishing and creek access ramp
The Bohn Park creek-side trail system connects the park with downtown Lyons and the surrounding neighborhoods
2D flood modeling results with two overflow channels on the S. Saint Vrain Creek in Lyons, CO

Lyons, Colorado

Bohn Park was devastated by the 2013 Colorado Flood. Record rainfall in the North St. Vrain Creek topped its banks and decimated Bohn Park. Almost all of the park’s amenities and infrastructure were damaged or completely destroyed.

S2O Design was part of the team selected to redesign Bohn Park and was tasked with restoring the North St. Vrain Creek. The project included extensive modeling and the design of overflow channels to increase flood capacity and control future flood events. The design also included the implementation of a variety of creek stabilization and habitat structures within the project area. The creek is very steep, with a maximum slope of 3%. To mediate the steep slope and respect the public’s desire to keep the park looking natural, S2O Design designed several cross vane structures, as well as a series of pools and riffles to curtail the steep slope. Finally, the design included deep pools, wetland areas, and structure and boulder placement that provide habitat for aquatic species throughout the year.

Additionally, balancing recreational creek access and protection of the riparian habitat corridor was also a critical issue. On average, the park hosts 200 to 400 residents and visitors every weekend. The design addressed this issue by strategically placing hardened river access points allowing users to access the river for fishing and active creek recreation, and allowing riparian habitat areas to remain undisturbed and thriving.

Project Highlights

  • Extensive public outreach and public participation throughout the design process.
  • The design of three boulder cross vain structures and a series of defined pools and riffles.
  • The design and placement of habitat structures including: habitat boulders, rootwads, and a toe wood structure.
  • Detailed 2D hydraulic modeling of the park area that lead to the design of two overflow channels that lessened the impact of future flood events.