the highest priority sections already completed or under way.
Protecting streambanks has become more common in the last 10 years, Robinson said.
“ For a long time, rivers have been neglected and often were a dumping ground,” he said.
Development affects runoff, often putting more water into streams, and more water causes banks to erode and can destroy wetlands.
More erosion in rural areas isn’ t as catastrophic, but when banks erode in urban settings, stream destabilization becomes more critical and threatens infrastructure, Robinson explained. With Fossil Creek, the first reach the project team worked to protect, the stream cut into the bank and created a 15-foot vertical wall.
“ A light post and softball field scoreboard were being threatened, and a water quality pond was close to being breached,” he said.“ As erosion starts to impact infrastructure, it’ s a big deal.”
Essentially, the project has two components: bank stabilization and rehabilitating or creating wildlife habitat, Robinson explained. The bank stabilization component so far has involved using stabilization( such as rocks) along the toe of the streambank. It also includes developing healthy wetlands along
the banks by using willows to provide stabilization through those areas. This method is similar to that tested as part of the NCHRP research project.
Additionally, the project team is working to replace the banks with vegetation that will improve habitat for wildlife, a method that looks at injecting diversity and complexity into the ecosystem.
“ We’ re giving the river system a jump start,” Robinson said.“ We stabilize it, get the right structure in place, and then allow natural things to happen.”
This kind of work requires coordination between many disciplines. Ayres is responsible for the hydraulic and hydrology work, grading, bank stabilization, channel design, and geomorphology. Aquatic biologists look at species and how materials interact with habitats. Ecologists identify plants and soils and prepare permits. Fort Collins Utilities is managing the project under an Alternate Project Delivery System( APDS), in which all team members, including the construction contractor, work together from start to finish.
“ You need good communication and close coordination with your contractor for a project like this,” Robinson said.“ The APDS system provides for this because it brings all the people together.”
Left: Vegetated mechanically stabilized earth( VMSE) bank protection in Fossil Creek in Fort Collins, Colorado, immediately after construction. Right: Upper portion of Fossil Creek channel after one growing season.
Paquette said she’ s enjoyed being able to work outside with a great group of people that share the same goals: to make the stream channel more natural, stable, and better prepared to handle various degrees of flows and sediment loads.
The APDS system worked well with this project, providing a team atmosphere where everyone was able to contribute ideas and using everyone’ s strengths and experience.
“ Dusty( Robinson) has a lot of great ideas and experience and is willing to share and work with the team to get the work done,” Paquette said.
Personally, Robinson has found this project a perfect complement to his love of rivers. He is an avid rafter and kayaker and sees firsthand the value of the waterway.
“ When I see a river neglected and treated as an afterthought, it’ s a bummer because you know its potential,” he said.
– Tawny Quast
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