restoring the lower pawtuxet river
DESCRIPTION
Restoring the Lower Pawtuxet River. Public Meeting January 29, 2008. 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) - PowerPoint PPT PresentationTRANSCRIPT
Restoring the LowerPawtuxet River
Public MeetingJanuary 29, 2008
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)
The Pawtuxet River Authority was created by an act of the RI Legislature in 1972.
TITLE 46Waters and Navigation
CHAPTER 46-24Pawtuxet 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.
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
45
6
2
Project Overview
• Introductions
• Purpose of the project
• Fish biology/watershed ecology
• Project process
• 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
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?
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.”
River Herring or “Buckies”
American shad (Alosa sapidissima)
Blueback Herring (Alosa aestivalis) Alewife (Alosa pseudoharengus)
“Target Species”
Fishing for Buckies, About 1910
Historic Pawtuxet Falls
Early 1900’s
1800’s
Many changes over time
Pawtuxet Falls Today
BEDROCK
CONCRETE
CONCRETE
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 $$)
Scope of Work
Sediment Sampling and Analysis Bathymetric Survey Hydraulic Modeling Alternatives Evaluation
• Fish Passage• Ecological implications• Sediment Stability• Recreation• Morphology / Hydraulics
Fish Passage Barriers
• Dams
• Culverts
• Bridges
• Tide Gates
• Utility Crossings
• High Velocity
• Shallow Water
• Poor Substrate
• Water Temperature
• Low Oxygen
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
STUDY PROCESSDAM MANAGEMENT ALTERNATIVES
DATA COLLECTION
BASE DATANID
FEMASTATE AGENCIES
DESIGN PLANSHISTORY
OWNERSHIPAS-BUILT DATA
USE
DAM SAFETYHAZARD CLASSIFICATION
PHYSICAL INSPECTIONSPILLWAY CAPACITYSIZE CLASSIFICATION
OPERATIONAL HAZARDSSTRUCTURAL / GEOTECH .
SITE DATATOPOGRAPHY
WETLANDSRARE SPECIESHYDROLOGY
GEOLOGYHISTORIC VALUE
SEDIMENTSWATER QUALITYPUBLIC &
REGULATORYPARTICIPATION
IS DAMSAFE?
EMERGENCYREPAIRS ORDRAWDOWN
MARGINAL DAM
REPAIR ORREPLACE DAM
IDENTIFYALTERNATIVES
ELIMINATE DAM AND IMPOUNDMENTRETAIN DAM AND IMPOUNDMENTPROVIDE FISH PASSAGE LOWER
CREST
FISH LADDER
D/SRAMP
U/SRAMP
HIGH LEVELBY-PASS
CHANNEL
NO ACTION
OTHER
FULLREMOVAL
PARTIALBREACH
LOW LEVELBY-PASS
VERY SMALLOR LOW RISKDAM, SIMPLE
DECOMMISSION
LIMITED FEASIBILITY STUDY
SITE SPECIFIC TOPICS
PUBLIC & REGULATORYPARTICIPATION, SELECT
ALTERNATIVE
IMPLEMENTATIONCONSTRUCTION PLANS
SPECIFICATIONSCOST ESTIMATES
FUNDINGEASEMENTS
REGULATORY PERMITSCONSTRUCTION ADMINISTRATION
SITE RESTORATIONAS-BUILTS
OPERATIONAL PLANEMERGENCY RESPONSE PLAN
DETAILED FEASIBILITY STUDYHYDRAULIC ANALYSIS
SEDIMENT TESTINGSEDIMENT TRANSPORT
CHANNEL MORPHOLOGYU/S AND D/S IMPACTSWETLAND IMPACTS
LAND USE / AESTHETICSAQUATIC SPECIES
RECREATIONLAND RIGHTS
WATER RIGHTSUTILITIES
ACCESSFINANCIAL IMPACTS
CONSTRUCTION METHODSSITE RESTORATIONEROSION CONTROL
YESNO
YES
NO
For additional information,please contact:
James MacBroom, P.E.
716 - 726 South Main StreetCheshire, Connecticut 06410Telephone (203) 271 -1773Fax (203) 272 -9733E-Mail: [email protected]
Study Process Design Management
Alternatives
• Type & Condition of Dam (Safety)Type & Condition of Dam (Safety)
• Site Limitations (Utilities, Access) Site Limitations (Utilities, Access)
• Up & Downstream Issues (Bridges/Structures, Up & Downstream Issues (Bridges/Structures, Tributaries)Tributaries)
• Environmental Permitting Environmental Permitting
• Alternatives AnalysisAlternatives Analysis
Engineering Issues
Design Variables
• Channel Morphology
• Channel Gradient
• Profile Pattern
• Channel Width & Depth
• Mannings Roughness Coefficient
• Materials
• In-Channel Features
• Sediment Transport / Stability
0
2
4
6
8
0 2 4 6 8
VELOCITY (FPS)
DE
PT
H (
FE
ET
)
TOO DEEP
TOO FAST
TOO SHALLOW
Fish Criteria
Channel Profile
No Action
Full Removal
Existing Conditions Low Tide
Full Removal Low Tide
Existing Conditions Low Tide
Partial Removal Low Tide
Partial Removal
Summary of Water Surface ElevationsControlled 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)
-130 70 ft. d/s of -1.58 1.37 -1.58 1.37 0.00 0.00-60 D/S face of -1.56 1.63 -1.56 1.63 0.00 0.00
-30
2 U/S face of -0.73 1.94 -0.73 1.94 0.00 0.0036 25 ft. d/s of Dam 2.16 5.55 2.16 5.55 0.00 0.00
61 D/S face of Pawtuxet Falls Dam 2.88 2.77 2.88 2.77 0.00 0.0065 Dam
70 U/S face of Pawtuxet Falls Dam 6.28 0.53 3.00 1.09 -3.28 0.56120 50 ft. u/s of Dam 6.28 0.66 3.01 1.15 -3.27 0.49420 350 ft. u/s of Dam 6.29 1.28 3.07 2.91 -3.22 1.63
1300 FEMA Section A 6.46 1.21 4.35 2.10 -2.11 0.89
1830 300 ft. d/s of Rhodes-on-the-Pawtuxet 6.59 1.23 4.79 1.82 -1.80 +0.593400 FEMA Section B 6.95 1.43 5.65 1.84 -1.31 0.405390 50 ft. d/s of 7.31 0.96 6.33 1.18 -0.98 0.225440 D/S face of 7.32 1.13 6.34 1.44 -0.98 0.31
5494
18520 FEMA Section H 9.96 1.34 9.83 1.38 -0.13 0.04
24460 D/S face of Route 37 Bridge 12.70 1.35 12.70 1.35 0.00 0.00
Full Removal with Upstream Ramp
Fish Ladder Design Criteria
• Low Velocity
• Water Depth
• Fish Entry
• Fish Exit
• Upstream Flow Control
• Variable River Stages
• Vertical Rise
Existing Conditions
Proposed Conditions
Fish Ladder
Goals and Issues Current 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 ideal Excellent Excellent Very good
Aesthetics No change Restoration 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 Unchanged Restore riverine habitat upstream of dam; restore tidal connection to estuary
Restore 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 None Minimal change expected; possible increase in flood storage
Minimal change expected; possible increase in flood storage
Minor None
Water Quality No change Modest improvement expected upstream of dam
Modest improvement expected upstream of dam
Minor improvement No change
Boating Flat Water Canoeing
Unchanged Reduced Reduced Slightly reduced Unchanged
Free Flowing Kayak
Unchanged Increased Increased Slightly increased Unchanged
Estuary Linkage Unchanged Potential improvement for skilled paddlers only
Potential improvement for skilled paddlers only
Creates new obstacle Unchanged
Sediment Bank Stability Unchanged Minimal change
expectedMinimal change expected
Minimal change expected
Unchanged
Bed Dynamics Unchanged Minimal change expected
Minimal change expected
Minimal change expected
Unchanged
Upstream Property Flooding
Unchanged Some improvement expected
Some improvement expected
Minimal change expected
Unchanged
Maintenance Minimal None Minimal Minimal Significant
Est. Cost N/A $375,000 $255,000 $545,000 $395,000
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
THANK YOU!