Big Meadows Culvert

Salmonid Restoration Planning and Assessments

Restoration Planning And Coordination Salmonid Habitat Assessment / Inventory
Project ID004 11 CW
Recovery DomainsInterior Columbia
Start Date10/23/2012
End Date06/30/2014
Last Edited10/21/2021
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This project is the first phase of a three phases to complete the removal of the Big Meadows Creek culvert fish passage barrier located approximately 1/4 mile east of Troy, Idaho.

Approximately six miles of stream was assessed for instream habitat condition, salmonid presence/absence, fish passage barrier inventory and habitat use by salmonids. Three miles of stream were identified as in need of restoration.

A habitat survey field data collection was completed on 36 acres and 18 acres were identified to be in need of restoration Discharge measurements were regularly recorded beginning in March 2013 and turbidity measurements were recorded in the spring of 2014.

The IDFG fisheries engineers coordinated with the Idaho Transportation Department (ITD) to draft three alternative designs and cost estimates for replacement/retrofitting of the Big Meadow Creek culvert. Big Meadows Creek flows south through a culvert under Highway 8 before draining into the West Fork Little Bear Creek. All three designs would improve passage to a degree but the bridge option would most effectively solve fish passage and provide the lowest future maintenance for ITD.

These alternatives are: 1) Install baffles on existing culvert 2) Culvert replacement with stream simulation arch culvert, and 3) Culvert replacement with bridge (preferred alternative). Technical reviews of these designs were conducted by two independent consultants who both provided comments supporting culvert replacement with a bridge. A Hydrologist/Watershed Restoration representative from the United States Forest Service visited the site and provided comments. Bonneville Power Administration (BPA) conducted a field review of the project and determined that it is a high risk project requiring engineering and technical oversight from BPA as implementation and permitting proceeds.

Additional funding will be solicited to conduct phase two (final design) and three (implementation of the selected alternative to remove the fish passage barrier.

Project Benefit    

Benefits will include improved access to spawning and rearing habitat and summer refugia for steelhead within the Big Meadows Creek tributary. This project will provide passage to over 9 miles of habitat that is currently unavailable due to passage constraints. Improved passage at this site will allow access to higher drainage habitat and may provide better flow and lower temperatures for additional spawning and rearing habitat within this productive drainage. This project will serve to proved a collaborative approach to steelhead population improvements as a sister project is being implemented on the West Fork Little Bear (Dutch Flat Dam Removal - PCSRF project 010 11 CW).


Metric Completed Originally
Planning and Assessment
  Stream Miles Assessed 6.00 9.00

Funding Details

Report Total:$51,783

Project Map


Big Meadows Culvert    

  • Worksite Identifier: Big Meadows Culvert
  • Start Date: 10/22/2012
  • End Date: 06/30/2014
Area Description
Potlatch River, 17060306, West Fork Little Bear Creek

Location Information

  • Basin: Clearwater
  • Subbasin:
  • Watershed:
  • Subwatershed:
  • State: Idaho
  • Recovery Domain: Interior Columbia
  • Latitude: 46.733103
  • Longitude: -116.756872


  • Snake River Basin Steelhead DPS




  • B.0 Salmonid Restoration Planning and AssessmentsY (Y/N)
    •      . . B.0.a Planning And Assessment Funding 51,783.00
    •      . . B.0.b.1 Area Encompassed 200.0
    •      . . B.1 Restoration Planning And CoordinationY (Y/N)
      •      . . . . B.1.a Planning and Coordination funding 30,034.00
      •      . . . . B.1.b.11 Engineering/design work for restoration projectsY (Y/N)
        •      . . . . . . B.1.b.11.a
          Name of plan implemented
          Latah SWCD. 2007. Potlatch River Watershed Management Plan. Moscow, Idaho
        •      . . . . . . B.1.b.11.b
          Description and scope of the plan implemented
          This project funded the phase I, initial engineering design for mitigating a fish passage barrier. Three alternative designs were developed by IDFG engineers to mitigate the passage barrier at the Big Meadows Creek culvert under Idaho Hwy. 8, east of Troy, Idaho. These alternatives were conveyed to the IDFG habitat biologist (project sponsor) in a report entitled, Technical Memorandum, dated January 9, 2014. This document identified the current conditions of the culvert, the current instream conditions directly above and below the existing culvert, three alternative treatments to mitigate the passage barrier, and a recommendation for the preferred alternative. The alternatives were reviewed by two independent consultants (K35, OR and River Design Group, MT), a USFS hydrologist / watershed restoration specialist, and the Bonneville Riparian Technical Team. Each of these groups identified replacing the existing culvert with a bridge as the preferred alternative as was the recommendation of the IDFG engineers who developed the Technical Memorandum. The existing culvert is approximately 40 years old and is lined with concrete. The 170' culvert maintains velocities that prohibit salmonid passage during most flows. Elimination of passage barriers is identified as the highest priority in the forested reaches of the West Fork Little Bear sub-watershed in the Potlatch Plan. Application for funding of the final design (phase II) will be made in the near future, followed by application for implementation funding.
      •      . . B.2 Salmonid Habitat Assessment / InventoryY (Y/N)
        •      . . . . B.2.a Habitat Assessment Funding 21,749.00
        •      . . . . B.2.c Instream SurveyY (Y/N)
          •      . . . . . . B.2.c.1 Type of instream survey (LOV)
          •      . . . . . . B.2.c.2 Stream miles assessed 6.00
          •      . . . . . . B.2.c.3 Stream miles assessed that contained salmonids 6.00
          •      . . . . . . B.2.c.4 Stream miles assessed that needed restoration 3.00
          •      . . . . . . B.2.c.5 Stream miles assessed for regulatory actions .00
          •      . . . . . . B.2.c.6 Fish passage impediments identified 1
        •      . . . . B.2.d Habitat surveysY (Y/N)
          •      . . . . . . B.2.d.1 Type of habitat survey/assessment (LOV)
          •      . . . . . . B.2.d.2 Amount of habitat assessed 36.0
          •      . . . . . . B.2.d.3 Amount of habitat assessed that needed restoration 18.0