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Restoring the Lower Pawtuxet River Public Meeting January 29, 2008
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Meeting Agenda 7:10-7:15 Welcome (Bob Nero, Chairman, PRA) 7:15-7:25 River Restoration in R.I. (Dir. Mike Sullivan, DEM) 7:25-7:45 Project Overview (Tom Ardito, NBEP) 7:45-8:15 Restoration Alternatives & Recommendations (Jim MacBroom, MMI) 8:15-8:45 Open Discussion 8:45-9:00 Funding & Next steps (Ardito)
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The Pawtuxet River Authority was created by an act of the RI Legislature in 1972. TITLE 46 Waters and Navigation CHAPTER 46-24 Pawtuxet River Authority SECTION 46-24-2 § 46-24-2 Pawtuxet River authority created. – A board to be known as the Pawtuxet River authority is hereby created. The board shall be a body corporate and politic, constituting a public benefit corporation, and shall serve as the governing body of the authority for the purposes of this chapter. The powers of the corporation shall be vested in and exercised by the majority of the members of the board hereby created and in office.
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Current Projects 1. Fish passage at Pawtuxet Falls 2. Canoe launch and nature area at Pocasset 3. Pontiac canoe launch and 48 acre wildlife area 4. Riverwalk at Royal Mills 5. Veterans Square fishing and canoe access 6. Riverwalk & Harris Dam fishing area 1 3 4 5 6 2
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Project Overview Introductions Purpose of the project Fish biology/watershed ecology Project process
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Pawtuxet River Authority and Watershed Council Narragansett Bay Estuary Program Save The Bay, Inc. R.I. Coastal Resources Management Council R.I. Corporate Wetlands Partnership R.I. Department of Environmental Management U.S.D.A. Natural Resources Conservation Service National Oceanic and Atmospheric Administration U.S. Environmental Protection Agency U.S. Fish and Wildlife Service And, we hope, YOU!!! People who care about the environment of the Pawtuxet River & the community of Pawtuxet Village Project Partners
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Goal: To restore historic runs of migratory fish (particularly river herring and shad) to the lower Pawtuxet River Purpose: To improve the environment of the Pawtuxet River, Narragansett Bay, and historic Pawtuxet Village Benefits: Increase Fish & Wildlife in Pawtuxet River and Narragansett Bay Improve Rhode Island’s Fresh and Salt Water Fisheries Restore Historic Ecological Connection between Bay and Watershed Restore Historic Natural and Cultural Feature of Pawtuxet Village Why Restore the Lower Pawtuxet?
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R.I. Inland Fisheries Commission, 1869: “This generation has seen our streams filled with shad and herring…..The principle rivers in the State which were formerly the home of the salmon, shad and herring, are the Blackstone, Pawtuxet and Pawcatuck, and these have become so obstructed with dams, that they no longer offer a passage to their upper waters, which nature prompts the fish to seek at spawning time.”
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River Herring or “Buckies” American shad (Alosa sapidissima) Blueback Herring (Alosa aestivalis)Alewife (Alosa pseudoharengus) “Target Species”
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Fishing for Buckies, About 1910 Historic Pawtuxet Falls Early 1900’s
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1800’s Many changes over time
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Pawtuxet Falls Today BEDROCK CONCRETE
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Restoration Process (What We’re Doing) 1.Feasibility Study: Completed 2005 2.Hydrologic Modeling & Alternatives Analysis: Completed 2007/08. Considerations included: a.Fish passage for target species b.Visual Impacts (Aesthetic Considerations) c.Other Environmental Impacts (Habitat, Wetlands, Water Quality) d.Recreation (canoeing, kayaking, fishing) e.Sediment (movement, exposure, erosion, siltation) f.Flooding g.Maintenance h.Cost of Alternatives 3.Next steps: a. Finalize alternative b.Begin permitting c.Funding & Construction (2009, pending $$)
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Scope of Work Sediment Sampling and Analysis Bathymetric Survey Hydraulic Modeling Alternatives Evaluation Fish Passage Ecological implications Sediment Stability Recreation Morphology / Hydraulics
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Fish Passage Barriers Dams Culverts Bridges Tide Gates Utility Crossings High Velocity Shallow Water Poor Substrate Water Temperature Low Oxygen
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Restoration Alternatives 1.No Action—Leave River As-Is 2.Full Dam Removal 3.Partial Dam Removal 4.Full Removal with construction of New Rock Ramp Upstream 5.Denil Fish Ladder
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Study Process Design Management Alternatives
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Type & Condition of Dam (Safety)Type & Condition of Dam (Safety) Site Limitations (Utilities, Access)Site Limitations (Utilities, Access) Up & Downstream Issues (Bridges/Structures, Tributaries)Up & Downstream Issues (Bridges/Structures, Tributaries) Environmental PermittingEnvironmental Permitting Alternatives AnalysisAlternatives Analysis Engineering Issues
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Design Variables Channel Morphology Channel Gradient Profile Pattern Channel Width & Depth Mannings Roughness Coefficient Materials In-Channel Features Sediment Transport / Stability
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0 2 4 6 8 0 2 4 68 VELOCITY (FPS) DEPTH (FEET) TOO DEEP TOO FAST TOO SHALLOW Fish Criteria
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Channel Profile
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No Action
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Full Removal Existing Conditions Low Tide Full Removal Low Tide
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Existing Conditions Low Tide Partial Removal Low Tide Partial Removal
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Summary of Water Surface Elevations Controlled Breach Mean April Flow @ Low Tide SECTION CROSS SECTION DESCRIPTION EXISTING CONDITIONS PROPOSED CONDITIONS EXISTING VERSUS PROPOSED Elevation (ft) Velocity (ft/s) Elevation (ft) Velocity (ft/s) Elevation (ft) Velocity (ft/s) -13070 ft. d/s of -1.581.37-1.581.370.00 -60D/S face of -1.561.63-1.561.630.00 -30 2U/S face of -0.731.94-0.731.940.00 3625 ft. d/s of Dam 2.165.552.165.550.00 61D/S face of Pawtuxet Falls Dam 2.882.772.882.770.00 65Dam 70U/S face of Pawtuxet Falls Dam 6.280.533.001.09-3.280.56 12050 ft. u/s of Dam 6.280.663.011.15-3.270.49 420350 ft. u/s of Dam 6.291.283.072.91-3.221.63 1300FEMA Section A 6.461.214.352.10-2.110.89 1830300 ft. d/s of Rhodes-on-the-Pawtuxet 6.591.234.791.82-1.80+0.59 3400FEMA Section B 6.951.435.651.84-1.310.40 539050 ft. d/s of 7.310.966.331.18-0.980.22 5440D/S face of 7.321.136.341.44-0.980.31 5494 18520FEMA Section H 9.961.349.831.38-0.130.04 24460D/S face of Route 37 Bridge 12.701.3512.701.350.00
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Full Removal with Upstream Ramp
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Fish Ladder Design Criteria Low Velocity Water Depth Fish Entry Fish Exit Upstream Flow Control Variable River Stages Vertical Rise
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Existing Conditions Proposed Conditions Fish Ladder
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Goals and IssuesCurrent Conditions/No Action Alternative Alt. 1: Dam Removal Alt. 2: Partial Dam Removal (Recommended) Alt. 3: Dam Removal With Ramp Alt. 4: Denil Fish Ladder Fish Passage None for herring and shad; some eel passage probable Some but not idealExcellent Very good Aesthetics No changeRestoration of flowing river and natural falls Portion of old concrete dam visible Restoration of natural falls, but ramp visible Minimal impact to dam, but ladder visible Habitat UnchangedRestore riverine habitat upstream of dam; restore tidal connection to estuary Restore some riverine habitat while retaining most of existing pond conditions Unchanged Effect on Wetlands NoneMinimal change expected; possible increase in flood storage MinorNone Water Quality No changeModest improvement expected upstream of dam Minor improvementNo change Boating Flat Water Canoeing UnchangedReduced Slightly reducedUnchanged Free Flowing Kayak UnchangedIncreased Slightly increasedUnchanged Estuary Linkage UnchangedPotential improvement for skilled paddlers only Creates new obstacleUnchanged Sediment Bank Stability UnchangedMinimal change expected Unchanged Bed Dynamics UnchangedMinimal change expected Unchanged Upstream Property Flooding Unchanged Some improvement expected Minimal change expected Unchanged Maintenance MinimalNoneMinimal Significant Est. Cost N/A$375,000$255,000$545,000$395,000
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Funding & Next Steps Feb. 2008 –Evaluate Public Comments –Meet with Regulators March 2008 –Finalize Preferred Alternative –Another Public Meeting to Present 2008 –Permitting –Design & Engineering –Fundraising: Non-Federal Match, approx. $100,000 2009: Construction
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THANK YOU!
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