STREAMS

Smith River Streambank Stabilization

Montana Fish Wildlife & Parks

Disciplines: Survey, Hydrology & Hydraulics, Bioengineering, Drafting, Contracting Documents, Construction Oversight

This project intended to stabilize an eroding streambank impacting both public and private property. Coldwater Engineering was a member of the design team and provided engineering support and construction oversight to the project. The client, private property owner, and design team worked together to provide a stabilized streambank utilizing bioengineering techniques.

Requirements: Environmental project goals ruled-out the use of traditional hard armor (riprap). Instead, the project intended to utilize bioengineering techniques to provide an environmentally friendly and aesthetically pleasing solution.

Strategy/Approach: Coldwater Engineering conducted the site survey, collecting topographic and bathymetric survey data. Design surfaces and a project plan set were developed to estimate construction quantities and to provide contracting documents. A hydrologic and hydraulic analysis was performed to quantify flood risk and to estimate the channel stage/discharge relationship. Hydraulic calculations assisted with backfill and streambank toe aggregate specifications, sizing material based on the flood risk analysis and project design requirements. Coldwater Engineering also provided construction oversight services, providing field engineering, tracking quantities, and collecting as-built data.

Miller Creek Stream Restoration

Clark Fork Coalition

Disciplines: Survey, Hydrology & Hydraulics, Bioengineering, Floodplain Permitting, Construction Inspection

The Miller Creek project intended to restore aquatic and riparian habitat. The project was located within a FEMA-designated floodplain, requiring the project to meet county floodplain regulations. Coldwater Engineering was a member of the design team and provided survey, engineering, and floodplain permitting support to the project.

Requirements: The project required a design that was permittable while also meeting environmental goals.

Strategy/Approach: A combination of floodplain lowering, floodplain treatments, and streambank treatments were utilized to improve floodplain connectivity and to improve aquatic habitat. A hydrologic and hydraulic analysis was conducted to determine proposed project impacts relative to the floodplain. Additionally, streambank calculations were performed to demonstrate project compliance with permitting regulations. Coldwater Engineering developed floodplain permitting submittals to document findings and attended a site tour to discuss the project with regulators.