Trends Spring 2016 | Page 11

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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