1. Milltown Phase II Draft Restoration Plan
How about a figure of picture here. I had a picture of the 1908 flood, but I think we should have a design picture or figure would be appropriate now.
Doug Martin, State of Montana
Gary Decker, WestWater Consultants, Inc.
River Design Group, Inc.
April 1, 2005
University of Washington Libraries

2. Presentation Outline Draft Conceptual Restoration Plan review
Restoration plan overview
Phase II data collection and analysis
Summary results
Draft design plan concepts
Schedule moving forward
You could put a figure here if you have one.
Clark Fork Symposium 2005

3. Milltown Reservoir Sediment Operable Unit
Please keep this picture, I want to highlight where remediation is taking place.
Clark Fork Symposium 2005

4. Restoration Plan Objectives
Restore the Clark Fork and Blackfoot rivers in the Milltown Reservoir Sediment Operable Unit (MRSOU) to be naturally functioning and self-maintaining
Use native materials to the extent practical, for stabilizing channels and floodplain
Improve water quality by stabilizing contaminated sediments to be left in place
Provide high quality habitat for fish and wildlife
Clark Fork Symposium 2005

5. Restoration Plan Objectives
Maintain existing infrastructure stability
Improve aesthetic values in the area by creating a diverse, natural setting
Provide recreational opportunities such as river boating, fishing, and trail access for hiking and bicycling
Clark Fork Symposium 2005

6. Draft Conceptual Restoration Plan
Intent of DCRP
Primary purpose was to develop a cost estimate for settlement and planning purposes
Incorporated preliminary data to offer potential restoration options for the Remediation Plan – natural channel vs. armored channel
Plan developed to gauge public support for dam removal and restoration of Clark Fork and Blackfoot rivers
You could put a figure here if you have one.
Clark Fork Symposium 2005

7. Draft Conceptual Restoration Plan
DCRP Accomplishments
Determined scope of restoration efforts
Better understanding of Milltown Dam effects
Developed information for integration with Remediation Actions
Provided basis for removing the Milltown Dam powerhouse and Stimson Dam
Favorable public comments for plan
You could put a figure here if you have one.
Clark Fork Symposium 2005

8. Public Process and Design Phases
Phase I Draft Conceptual Restoration Plan
(February 2003)
Public Review
/Public Meetings /Responsiveness Summary
Amended
Conceptual Plan
(June 2004)
Phase II Data
Collection Activities
(ongoing)
Draft Phase II
Design Plan and Peer Review
(April 2005)
Public Review
Process/Public Meetings
Final Phase III
Design Plan
Clark Fork Symposium 2005

9. Project Constraints Sediments left in place Infrastructure
Cultural sites
Integration with remediation
Continuity with upstream and downstream reaches
Landownership
Clark Fork Symposium 2005

10. Phase II Data Collection and Analysis
Clark Fork Symposium 2005
University of Washington Libraries

11. Phase II Purpose and Goals
Validate DCRP assumptions and complete detailed data collection and analysis
Determine appropriate channel morphology
Determine design criteria for Final Design phase
Update project cost estimates, phasing, and construction sequencing
Assess potential restoration risk for restoration activities
Address changes in wetland conditions from existing to proposed design – revegetation plan
Clark Fork Symposium 2005

12. Questions to be Answered
What were the most probable historical channel and floodplain morphologies?
What are the current channel and floodplain conditions and how have they been influenced by historical and contemporary land uses?
Can we restore the system to historical conditions given the project constraints and upstream conditions?
Clark Fork Symposium 2005

13. Field Data Collection Overview
Data collection to characterize conditions and to develop design plan
6 reaches on CFR, 4 on BFR
Field techniques
Geomorphic surveys
Reference and existing conditions
Bed material characterization
Gage station calibration
Riparian condition assessment
Bank stability and erosion potential
Valley morphology and transitions
Clark Fork Symposium 2005

14. Remote Data Collection Overview
Historical conditions research
Current and time series aerial photograph interpretation
University of Washington Libraries
Clark Fork Symposium 2005

15. Data Analysis Techniques
Existing and reference conditions – departure analysis
Hydraulic modeling
Incipient particle motion and sediment transport
Valley morphology
Channel planform
Ice floe considerations
Clark Fork Symposium 2005

16. Questions 1: Historical Channel and Floodplain Morphologies
University of Washington Libraries
Map from the Lewis and Clark Journals. Highlight of the Clark Fork and Blackfoot confluence.
… the Cokahlahishkit R which falls in on the N.E. side [of the Clark Fork River], is 60 yds. wide deep and rapid. the banks bold not very high but never overflow. the East fork [Clark Fork River] below its junction with this stream is 100 yds. wide and above it about 90. the water of boath are terbid but the East branch much the most so; their beds are composed of sand and gravel.
M. Lewis, July 3, 1806
Reviewed historical maps, journals, photos, and earliest aerial photographs
Surveyed and evaluated project area and reaches with similar valley morphologies
Regime equations addressing channel morphology (Millar, Knighton)
Regime Equation Results for CFR3
Predicted Observed
Regime equation predicts a meandering channel type
Millar, 2000
CONCLUSION: Reviewed information and data suggest the Clark Fork River was historically a meandering river system. The historical channel is believed to have transitioned from an unconfined to confined system without braiding.

17. Questions 2: Current Conditions & Land Use Effects
Reviewed historical maps, and journals
Time series aerial photograph analysis
Departure analysis comparing existing and reference conditions
CONCLUSION: Human disturbance in the Upper Clark Fork River watershed and more immediate floodplain corridor perturbed the system. Periodic large magnitude flood events unravel the stream network. Inter-flood periods characterized by channel recovery.
Clark Fork Symposium 2005

18. Questions 2: Current Conditions & Land Use Effects
Reach
Bankfull
Width (ft)
Average
Depth (ft)
Max Riffle XS
Area (ft2)
Width/Depth Ratio
Braided
(n = 3)
708
( )
1.7
( )
6.4
( )
1,208
(1,128-1,361)
427
( )
Reference
(n = 2)
183
( )
3.2
( )
4.9
( )
572
( ) 60
(37-77)
Land use effects date to 1860s
Milltown Dam
Mining
Transportation corridor
Channel straightening
Grazing
Agriculture
Land development
Braided Reach XS
Reference Reach Riffle XS
Clark Fork Symposium 2005

19. Questions 3: Restoration Potential within Existing Constraints
Reference reach data from similar systems
Hydraulic and sediment transport modeling results
Riparian vegetation assessment
CONCLUSION: It will be possible to reconstruct the channel and floodplain to emulate historical conditions. An upstream reference reach has maintained a functioning meandering pattern for 60+ years. Limiting project risk will be a priority.
Clark Fork Symposium 2005

20. Phase II Draft Design Plan
Clark Fork Symposium 2005
University of Washington Libraries

21. Draft Design Plan
Applied reference reach data, modeling results, and regime equations to develop draft design plan
Channel grading plan through reservoir to be integrated with remedial action
Maintain channel stability through contaminated sediment reaches
Incorporate off-channel habitats and floodplain wetlands in draft channel design plan
Comprehensive revegetation plan
Clark Fork Symposium 2005

22. Draft Design Plan
Clark Fork Symposium 2005

23. Summary – Project Schedule
Preparing Draft Design Plan: Due April 15
Peer Review Process: April 15 – May 27
Incorporate Trustee and Peer Review Comments
Collect Final Data
Complete Final Design
Clark Fork Symposium 2005