Mission Creek Watershed Fish Passage Collaboration- This project was brought to Northwest Management Inc in 2012 by the Evergreen County Highway District in Northern Idaho. The need for new infrastructure to re-establish endangered steelhead above the pictured barrier and alleviate public safety concerns of the Highway District at this crossing were the projects objectives. NMI developed a project proposal and application for cost-share funding in partnership with the Nez Perce Tribe, the Highway District and three private landowners. The project application was to the Idaho Governor’s Office of Species Conservation and we were successfully awarded funds in spring of 2013. NMI in combination with the Nez Perce Tribe completed the documentation required for federal permitting, culturally sensitive area assessment, project development. This project was completed in the fall of 2013 during low-water conditions and received outstanding comments from the Idaho Governor’s Office of Species Conservation, the Evergreen Highway District, and local residents.
Northwest Management Inc provides balanced solutions, technical staffing, and professional services to meet the management challenges facing today’s natural systems. We value the high-level results gained through collaboration and believe sustainable solutions are achieved only through effectively balancing environmental, social, and economic values. Northwest Management Inc anchors it’s success in more than 30 years of field experience throughout the western U.S., a well-established team of resource professionals, and cutting-edge technology.
Surveys for steelhead and rainbow trout as well as site exclusion-netting were performed by the Nez Perce Tribe with participation from local landowners and NMI staff.
Following removal of the existing culvert barrier, stream banks were shaped to accommodate the stream energy of high spring runoff and the development of riffle to pool habitat.
Placing geotextile fabric below the 100-year high water mark before installation of channel armament further stabilizes the stream banks and bridge abutments also minimizing sediment input to the stream following construction.
The use of boulders 3-4 feet in diameter for stream riprap helps to dissipate steam energy, create turbulent and backwater habitat for juvenile fish and protect the road-crossing infrastructure resulting in a “zero” maintenance fish-friendly upgrade from the previous structure.
The placement of pre-cast concrete sills for the bridge allowed us to minimize disturbance and alleviate potential water quality concerns associated with forming concrete near water.