Gold Ray Dam Interagency Technical Team Meeting

Transcription

1 Gold Ray Dam Interagency Technical Team Meeting

2 Agenda Public Outreach, Funding, Monitoring EA/BA/Permit Updates Deconstruction Plans Fish Passage & Salvage Plan Hydraulic Modeling Next Steps

3 Public Outreach, Funding, Monitoring Fred Stockwell photograph

4 Environmental Assessment Update January 22 - Review draft EA to NMFS and County Two work sessions to provide comments/revisions February 15 - Revised draft EA ( pre-public release ) February 22 - Anticipate notice of availability 30 day public comment period NMFS review of comments, prepare and issue FONSI if appropriate

5 Environmental Assessment Update Purpose and need Action and No Action Alternatives No Action Alternative 1 Proposed Action Dam Removal Alternative 2 Dam Rehabilitation Alternative 2 Rehab dam, reconstruct fish ladders, rehab power facilities (including fish screens) Would not fully meet purpose and need of proposed action Cost estimate ~ $78M Power generation revenue ~ $1.5M/year

6 Environmental Assessment Update Environmental effects: Scope of analysis based on NMFS NEPA guidance and public input Environmental effects summarized in handout

7 Resource Area Anticipated Environmental Effects No Action Alternative Alternative 1 (Dam Removal) Geology and Soils - No direct impact; - Sediment would continue to accumulate behind Gold Ray Dam.. Land Use and Recreation Water Quality and Resources - No direct impact; - No changes to current land use or recreation activities - Sediment transport and the habitat values for native fish would continue to be reduced and elevated water temperatures in side channels would remain unsuitable for native coldwater fish. - Temporary disturbance of upland soils and sediments by construction activities. - Drawdown of the impoundment would cause release of some of the accumulate sediments behind the dam. - Removal of dam would restore more natural processes of sediment transport to the Rogue River. - Temporary effects on recreation during removal - Rogue River would be free-flowing allowing river users to experience uninterrupted river use throughout the entire reach. - Potential for low rapids and swift water attractive to rafters, kayakers and some canoers. - Increase some fishing/boating opportunities; decrease in others (related to flatwater conditions behind dam). - Temporary water quality impact during construction. More natural hydrologic and sediment transport processes would be reestablished. - Known wells in the area are in upland areas north of the reservoir could be affected. - Lower Kelly Slough and Tolo Slough, would likely revert to narrow channels, decreasing backwater ponds with high summer water temperatures. Alternative 2 (Dam Rehabilitation) - Temporary disturbance of upland soils and sediments by construction. - Accumulated sediments would remain in place. - Temporary adverse effects on recreation during construction. - No long term impact to recreation and land use. - Temporary water quality impact during construction due to increased turbidity. - No impact long term, however water quality would continue to be degraded and habitat values for native fish would continue to be reduced. Wetlands and Floodplains - No impact to wetlands, - No change to floodplains. - Construction effects to wetlands would be temporary and would result in a short term loss of wetland functions. - Existing wetlands are expected to become drier with the drop in river levels. - With the lower river level newly exposed banks in some areas would likely become new wetlands. - No change to wetlands downstream of the dam. - Effects to the floodplain upstream and downstream of the dam expected to be minimal. - Temporary construction effects to wetlands resulting in a short term loss of wetland functions. - One artificially created wetland (from water leaking from forebay) would cease to exist. - No impact to floodplains.

8 Resource Area Anticipated Environmental Effects No Action Alternative Alternative 1 (Dam Removal) Aquatic Biology - No change; Gold Ray Dam would remain as an impediment to fish passage for both migratory and resident fish species. - Short term adverse impacts to aquatic habitat and fish during dam removal (turbidity, removal of riparian vegetation, fish handling). - Restoration of the natural river channel/functions and sediment transport processes would benefit Rogue River fisheries. - Populations of nonnative warm water species adversely affected by dam removal Alternative 2 (Dam Rehabilitation) - Short term adverse impacts to aquatic habitat and fish during in-water work (turbidity, removal of riparian vegetation, fish handling). - Improved fish passage by reconstructing ladder to comply with NMFS and ODFW s guidelines; however, fish would still have to navigate through an artificial structure. - Dam would continue to create unfavorable habitat conditions for native fish Terrestrial Wildlife No Impact. - Temporary construction impacts would disturb wildlife. - No long-term changes. Vegetation No Impact. - Vegetation would be removed for construction; disturbed area will be replanted. - Vegetation composition will change following the Cultural and Historic Resources No impact, however the condition of the dam and associated structures would continue to deteriorate over time. change in upstream surface water levels. - Adverse effect on the archaeological resources and historic property, however components of the dam and appurtenances would be documented and salvaged prior to removal and following dam removal, a reconnaissance-level archaeological survey of the formerly submerged areas. - Temporary construction impacts would disturb. - No long-term changes - Vegetation would be removed for construction; disturbed area will be replanted. - Dam rehabilitation would affect the structures that contribute to the eligibility of the Gold Ray Dam for the National Register of Historic Places. - Potential to disturb archeological resources. Visual Quality and Aesthetics No Impact. - Temporary visual impacts during construction. - Visual quality of upstream area would change; previously submerged areas would become exposed and would appear like the downstream stretch of river over time. Transportation No Impact. - Temporary traffic delays during construction. - Long term increase in recreation related traffic. - Leaving abutment on south bank would preserve rail line. - Temporary visual impacts from during construction. - Power transmission lines and facilities would detract from the scenic quality of the area. - Temporary traffic delays during construction. Air Quality No Impact. Temporary air quality effects during construction - Temporary air quality effects during construction Noise No Impact. - Temporary noise effects during construction. - Temporary noise effects during construction. - Slight decrease in noise levels, water no longer cascading over dam. - Power generating equipment would add to the noise level in the general vicinity.

9 No Action Alternative Alternative 1 (Dam Removal) Alternative 2 (Dam Rehabilitation) Human Health and Safety No change; Gold Ray Dam would remain as a safety hazard and liability risk for Jackson County. - Eliminate the public safety hazards and liability risk for Jackson County. - Short-term risk to public safety during demolition. - No adverse impacts associated with accumulated sediments. - Limited road access to some areas opened to recreational use - Alleviate some safety concerns because the dam structure would be reinforced to decrease the likelihood of failure. - Would continue to pose a hazard to boaters and trespassers. Socioeconomic and Environmental Justice No Impact. - Construction would result in short term increase in economic activity in Jackson County. - Free-flowing conditions would be beneficial fishing guides that focus on native fishes, and would have adverse effects on guides that focus on the existing warm water fishery upstream of the dam. - Would benefit rafting guide services. - Construction would result in short term increase in economic activity in Jackson County. - Dam rehabilitation, and specifically the rehabilitation of power generation at the dam, would not be cost effective and would not provide an economic benefit for Jackson County. Cumulative Impacts No Impact. - Beneficial cumulative effect on native fish and fish habitat by removing the barriers to fish migration and therefore providing 153 miles of the Rogue River (from Lost Creek Dam to the mouth), and more than 330 mile including tributaries, free of human-made barriers. - Restoring a more natural sediment transport dynamic in the Rogue River. - Largely eliminate the backwater area and the associated fishing and other recreation opportunities. - Cumulative benefit to fish passage by improved fish ladder. - No change native fish habitat/fish passage in the Rogue River.

10 Wetlands Update Delineation Report Delineation report submitted to DSL (number WD ) Locations of wetlands/waters reviewed at previous meetings DSL / Corps reviewing

11 Cultural Resources Update Historic building DOE concurrence from SHPO in January Dam/hydropower project = National Register eligible Archaeology report complete Proposed action would have Adverse Effect (per Section 106 of NHPA) Mitigation: document; salvage components; interpret; post-removal survey Findings submitted for SHPO concurrence by end of February

12 Permitting Update Environmental Assessment 30 day public comment period (approx. Feb 26 Mar 23) NMFS review of comments Prepare and issue FONSI if appropriate Corps/DSL 404/Removal Fill permit application is nearly complete Expect to submit by end of February BA Submitted last week, preliminary findings: May affect, not likely to adversely affect listed SONCC coho ODFW approved in-water work variances

13 Project Approach Deconstruction Plan Multi-step plan with controlled drawdown of reservoir Minimizes risk for County Minimize upstream adult fish passage delays to approximately 3 days or possibly less Ensures dam removal and fish passage throughout deconstruction

14 Project Approach

15 Project Approach

16 July 1 Project Approach

17 Fish Passage Plan Revisions / Updates: Monitoring provisions Additional timing info Post-dam fish passage

18 Phase 1 Fish Passage upstream control weir for fish ladder

19 Phase 1 Fish Passage Split flow adjustable weir

20 Project Approach

21 Project Approach Phase 2 Fish Passage

22 Phase 2 Fish Passage Figure 4-6. The Savage Rapids dam removal project showing 1,300 cfs going through radial gates with an average velocity of 6 fps and channel width of less than 60 feet.

23 Phase 2 Fish Passage

24 Hydraulic Modeling

28 Longitudinal Profile

29 Reservoir Profile

30 Downstream Profile

31 Hydraulic Modeling Additional runs of the hydraulic model are being completed to further enhance the stability and prediction potential Long term results indicate some areas of deposition immediately downstream of the dam but it appears that most sediment will be washed through Degradation of the Rogue River stream bed is expected near Kelly Slough inlet and Bear Creek confluences, but the magnitude and extent of erosion upstream is under review

32 Summary Next Steps Finalize hydraulic modeling and sediment transport model Distribute Environmental Assessment Submit permit applications (joint permit) Develop Restoration Plan Continue with public outreach

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