Hemlock Dam Removal and Habitat Restoration

Salmonid Habitat Restoration and Acquisition

Project ID	2007-4-04
Recovery Domains	Lower Columbia River
Start Date	01/01/2008
End Date	02/29/2012
Year	2007
Status	Completed
Last Edited	01/26/2024

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Description

The dam has been removed. Riparian restoration has been completed. The USFS did conduct one final year of post-project monitoring to include: main channel, high-flow channel and floodplain cross-section and longitudinal profiles; year 3 substrate and macro-invertebrate monitoring; large wood and pool counts; upstream and downstream water temperatures; and photo point monitoring.

Project Benefit

Removal of the dam and restoration of this reach of Trout Creek is expected to improve upstream and downstream migration for Lower Columbia River steelhead, and to increase spawning and rearing habitat. Elimination of historic and continuing fish ladder passage issues at the dam will reduce the risk of predation and harassment and improve opportunities for successful migration and spawning. Removal of the reservoir will eliminate heating caused by the reservoir and temperature-related stresses on migrating fish throughout the lower two miles of Trout Creek. Removal of the dam and reservoir will dramatically improve habitat in the reservoir reach and downstream reaches of Trout Creek by re-initiating natural processes of sediment and debris routing. Substrates in the reach immediately upstream of the dam will change from sand and silt-dominated to gravel/cobble/boulder-dominated, and the two miles of sediment-starved reaches of Trout Creek downstream of the dam will be re-loaded with spawning grade gravels and cobble.

Accomplishments

Metric

Completed

Originally
Proposed

Instream Habitat

Stream Miles Treated

.35

Wetland Habitat

Acres Created

Acres Treated

2.0

Riparian Habitat

Stream Miles Treated

.70

Acres Treated

1.0

Fish Passage

Barriers Removed

Miles Opened

20.00

Source

Funds

PCSRF

$50,000

Report Total:

$50,000

Worksites

Hemlock Dam

Worksite Identifier: Hemlock Dam
Start Date:
End Date:

Area Description

No Area Description data was found for this worksite.

Location Information

Basin: Middle Columbia (170701)
Subbasin: Middle Columbia-Hood
Watershed:
Subwatershed:

State: Washington
Recovery Domain: Lower Columbia River
Latitude: 45.802
Longitude: -121.646

ESU

Lower Columbia River Steelhead DPS

Map

Photos

Metrics

C.0 Salmonid Habitat Restoration and AcquisitionY (Y/N)

. . C.0.a Habitat restoration and acquisition funding 50,000.00
. . C.0.b Length of stream treated/protected .35
. . C.0.c
Project identified in a Plan or Watershed Assessment

Wind River Watershed Analysis 1996 and 2001; Lower Columbia River Salmon Recovery Plan, 2004; Wy-Kan-Us-Mi Wy-Kish Wit
. . C.0.d.1 Project Monitoring (LOV)
. . C.0.d.2 Monitoring Location (LOV)

. . C.0.d.3

Monitoring text (from Phase I)

Monitoring of the dam removal will be done to evaluate compliance with state water quality standards, terms and conditions from the Biological Opinion that was done for this project, and with mitigation described in the Hemlock Dam FEIS. Monitoring will also be done to evaluate the effectiveness of the project in meeting stated objectives for dam removal and habitat improvement. Project monitoring will begin prior to any ground disturbance and in some cases years prior to project implementation to establish background conditions. Monitoring will include the following areas at a minimum, and the actual plan will be developed in cooperation with other agencies and interested parties: 1) Water quality monitoring; 2) Geomorphic monitoring; 3) Habitat monitoring; and 4) Biological monitoring.

. . C.2 Fish Passage ImprovementY (Y/N)
- . . . . C.2.a Fish Passage Funding 35,000.00
- . . . . C.2.b.1 Length of stream made accessible 20.00
- . . . . C.2.b.3 Type of blockage/barrier (LOV)
- . . . . C.2.b.4 Number of blockages/impediments/barriers impeding passage 1
- . . . . C.2.c.1 Fish passage blockages removed or altered (other than road crossings reported in C.2.f to C.2.i)Y (Y/N)
  - . . . . . . C.2.c.2 Number of blockages/impediments/barriers removed/altered 1
- . . C.4 Instream Habitat ProjectY (Y/N)
  - . . . . C.4.a Instream Habitat Funding 5,000.00
  - . . . . C.4.b Total length of instream habitat treated .35
  - . . . . C.4.c.1 Channel reconfiguration and connectivityY (Y/N)
    - . . . . . . C.4.c.2 Type of change to channel configuration and connectivity (LOV)
    - . . . . . . C.4.c.3 Miles of stream treated for channel reconfiguration and connectivity .35
    - . . . . . . C.4.c.4 Miles of off-channel stream created through channel reconfiguration and connectivity .20
    - . . . . . . C.4.c.6 Instream pools created/added through channel reconfiguration and connectivity 5
  - . . . . C.4.d.1 Channel structure placementY (Y/N)
    - . . . . . . C.4.d.2 Material used for channel structure (LOV)
    - . . . . . . C.4.d.3 Miles of stream treated through channel structure placement .35
    - . . . . . . C.4.d.5 Pools expected to be created through channel structure placement 5
    - . . . . . . C.4.d.7 Number of structures placed in channel 1,200
  - . . C.5 Riparian Habitat ProjectY (Y/N)
    - . . . . C.5.a Riparian Habitat Funding 5,000.00
    - . . . . C.5.b.1 Total riparian miles streambank treated .70
    - . . . . C.5.b.2 Total Riparian Acres Treated 1.0
    - . . . . C.5.c.1 Riparian plantingY (Y/N)
      - . . . . . . C.5.c.2
        Species of plants planted in riparian
        
        See page 51 of the final report
      - . . . . . . C.5.c.3 Acres planted in riparian .7
    - . . C.8 Wetland ProjectY (Y/N)
      - . . . . C.8.a Wetland funding 5,000.00
      - . . . . C.8.b Total acres of wetland area treated 2.0
      -      . . . . C.8.d.1 Wetland plant removal/controlY (Y/N)
        
             . . . . . . C.8.d.2
        Species (scientific) name(s) of wetland plants removed
        
        Canary Reed Grass
        
             . . . . . . C.8.d.3 Acres of wetland treated .4
      - . . . . C.8.f.1 Artificial wetland createdY (Y/N)
        
        . . . . . . C.8.f.2 Artificial wetland acres created .5