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Wetland Review Checklist
Bozeman Stockyard Bank Stabilization
5. Project narrative for proposed activity.
The East Gallatin River is causing erosion of a streambank and threatening the loss of a pole barn. This
streambank was stabilized in 2014 using relatively soft bio-engineering techniques that failed in May
2018. The current proposed solution is to stabilize the streambank by excavating material from the
streambed to create a pool and use that material to create a floodplain bench with a rock toe,
reinforced with footer logs and rootwads to prevent bank erosion. The floodplain bench will be
revegetated with native willow transplants or nursery stock, sod mats (to the extent possible), and seed
on top of native topsoil. See plan sheets in Drawings folder.
The site is a raw, eroding bank with some pasture grasses on the top of the bank. Some cobble and
broken concrete has been dumped at the toe of the bank to try and slow the rate of bank erosion. The
6.5 ft tall, nearly vertical bank, extends for roughly 170 feet along the east bank of the East Gallatin
River, 1500 feet upstream of its confluence with Bozeman Creek. Since 2018 the bank has continued to
erode its bank and is now threatening a pole barn, with less than 6 feet between the pole barn and the
top of the bank. Emergent wetlands occur as fringe along the banks upstream and downstream of the
eroding bank, but no wetlands occur along the eroding bank itself.
6. Description of why avoidance and less damaging alternatives have been rejected.
The previously restored bank used a softer bioengineering approach which ended up failing. A ‘harder’
approach, such as riprap, would accomplish the goal of the project to halt the bank erosion, but does not
take into account natural resource benefits to fish and other aquatic organisms. The proposed approach
attempts to balance these goals by creating aquatic and riparian habitat, but also including a more
substantial bio-engineered approach that incorporates some oversized cobble at the toe of the new
bank, as well as bio-degradable materials such as rootwads and planted willows in the mid to high bank
areas.
10. Locations and specification for all proposed activities, including direct and indirect impact of such
activities.
See Plan Sheets and Joint Permit Application Attachments
11. Source, method of transport and disposal of any fill materials, and certification that placement of fill
material will not violate any applicable State or Federal Statutes and Regulations.
Cubic yards/Linear feet Size and Type Source
18 ea. (~30 ft x 1.5 ft dia.) Rootwads (conifer and cottonwood) Big Sky, Cardwell
12 ea. (~30 ft x 1.5 ft dia.) Footer logs (conifer and cottonwood) Big Sky, Cardwell
13 ea. Mature willow transplants/Nursery willows On-site, local nursery
22 ea. Riparian shrubs (dogwood, wild rose, etc.)
40 cy Oversized cobble (D50 = 11 in.) Provided by contractor
164 cy Gravel On-site/Provided by contractor
70 cy Topsoil On-site, Provided by contractor
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12. Copies of any Section 404 wetland permits submitted or already obtained for the site.
See Joint Permit Application PDF Attachment.
13. Historical information regarding wetland permitting or mitigation on the site.
This streambank was stabilized in 2014 using relatively soft bio-engineering techniques that failed in
May 2018.