8:30 Sign in Hoosic River Revival Coalition!"#$%&&'()*+#$%(,-./0*)%(! 12-#30+4/#"5-(60 9:00 Welcome and Introductions 9:15 Goals for Today s Program: A Description of the Planning Process 9:30 First Session: Conditions, Issues and Challenges: Hoosic River 101 Presentation (45 minutes) Issues and Opportunities Breakout Groups (55 Minutes) Group Reporting (15 minutes) 12:00 Lunch & Presentation: Examples of River Focused Revitalization in other Communities (30 minutes) 1:00 Second Session: A Vision for the Future Introduction (15 minutes) Vision, Goals, and Objectives for the River Breakout Groups (75 minutes) Future Headline (10 minutes) Group Reporting (15 minutes) 3:00 Summary of the Community Conversation & Wrap up 3:15 Adjourn
The Second Step Prepared by: Milone & MacBroom, Inc. June 2010
Project Site
Study Sequence History Hydrology Fluvial Morphology Hydraulics Constraints Opportunities
ACTIVE RIPARIAN ZONES Thalweg Channel Channel Banks Riparian Wetlands Floodplains Terrace Scarps Terraces
nrcs
1993, 1997 MONTGOMERY & BUFFINGTON CLASSIFICATION
River Patterns Slope Discharge Relations X NB X SB X Main Church, 2002
1894 USGS MAP 1948 USGS MAP
1948: Pre Flood Project
PROGRESSIVE URBANIZATION OF A STREAM Floodplain Dam w/ Diversion Progression of Urbanization Wildlife Corridor Fill Direct Discharges Diverse Habitat Source of Organic Material & Shade Retaining Wall Filters Runoff & Sediment Original Stream Channel Filled Wetland & Natural Floodplain Piped Drainage Channelized Stream Realign Channel, Reduce Habitat Size & Value Culverted Tributaries Small Bridge Lined Channel Concrete Liner Culvert Uniform Channel Low Diversity MacBroom, 1998 Culvert
ITEM NORTH BRANCH Hydrology SOUTH BRANCH MAIN STEM DATA DATE Watershed, SM 41.7 74.7 115.8 Corps Design Flow,CFS FEMA 100 Year Flood, CFS Gauge 100 Year Flood, CFS *150 Percent of the Flood of Record 15,000* 8,200 24,300* 1946 11,800 7,228 16,550 1981 11,184 7,678 13,557 2010
NB REFERENCE BANKFULL DATA Width 52 60 Ft Depth 4 Ft Slope 0.015 0.02 Pattern Straight Sinuosity 1.0 Profile Rapids, Shallow Pool/Riffle
North Branch Hoosic River
Chute Data ITEM NORTH BRANCH SOUTH BRANCH MAIN STEM Width, Feet 45* 45* 85.6 Typical Depth, Feet 12 12 12 Mean Slope, Ft/Ft 0.0136 0.00715 0.00743 Bridges 5 4 1 Drop Structures 2 1 *As Built
Bulletin 17B Plot for North Branch Hoosic River Return Period 1.0 1.1 2 5 10 50 200 1000 10000 100000.0 10000.0 Flow (cfs) 1000.0 100.0 0.9999 0.999 0.99 0.9 0.5 0.2 0.1 0.02 0.0050.001 0.0001 Probability Computed Curve Expected Probability Curve 5 Percent Confidence Limit 95 Percent Confidence Limit Observed Events (Weibull plotting positions)
North Branch Stage Discharge Actual Reg. Line 25.0 20.0 Stage (ft) 15.0 10.0 5.0 0.0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 Discharge (cfs)[e5]
NORTH BRANCH HOOSIC RIVER CHANNEL TYPE COMPARISON Channel Type B F Flow Regime <D c >D c Grade Structures Existing Yes Sediment Load Coarse Sand Substrate Cobble Gravel Gradient, % 1.4 0.026
North Branch Hoosic River Alternate 1 Q2=2400 CFS Stability Curve Q = 2400 cfs Total Sediment Concentration = 50 ppm Stability Curve Q = 2400 cfs Total Sediment Concentration = 50 ppm Legend Stability Curve Legend Stability Curve 0.00045 0.00045 0.00040 0.00040 Slope Degradation Slope Degradation 0.00035 0.00035 0.00030 0.00030 Aggradation Aggradation 0.00025 0 50 100 150 200 Base Width, ft 0.00025 4 6 8 10 12 14 16 Depth, ft Bankfull Width & Depth Sand Load, Gravel Bed, 50 PPT
Compound Channel Alternate 1 112 110 M: 0.03 M :. 0 3 M : 0. 0 3 M:.06 M:.03 Legend Ground 108 Elevation (ft) 106 104 102 100-600 -400-200 0 200 400 600 Station (ft) Cobble Bed, Sand Load, Low Gradient
Upper South Branch Hoosic River Reference Reach
South Branch Hoosic River
South Branch Hoosic River Q2=1115 CFS Stability Curve Q = 1115 cfs Total Sediment Concentration = 30 ppm Stability Curve Q = 1115 cfs Total Sediment Concentration = 30 ppm Legend Stability Curve Legend Stability Curve 0.00045 0.00045 0.00040 0.00040 Slope Degradation Slope Degradation 0.00035 0.00035 Aggradation 0.00030 0.00030 Aggradation 0.00025 0 20 40 60 80 100 120 140 160 Base Width, ft 0.00025 2 4 6 8 10 12 14 Depth, ft Sand Load, Gravel Bed, Bank n=0.04
DE CHANNELIZE SOUTH BRANCH Create Backwater Pools Replant Existing Dike Re Naturalize Channel Remove Grade Drop Relocate Dike
SOUTH BRANCH BASE FLOWS
SOUTH BRANCH FLOODPLAIN RESTORATION Return Flow Re Establish Oxbow Wetland Pool New Channel Upstream Diversion
SB Low Flow Diversion Stability Curve Q = 150 cfs Total Sediment Concentration = 50 ppm Stability Curve Q = 150 cfs Total Sediment Concentration = 50 ppm Legend Legend 0.0020 (> Valley Slope) Stability Curve 0.0020 (> Valley Slope) Stability Curve 0.0018 0.0018 Slope 0.0016 0.0014 Degradation Slope 0.0016 0.0014 Degradation 0.0012 0.0012 0.0010 Aggradation 0.0010 Aggradation 0.0008 0.0008 0.0006 0 10 20 30 40 50 60 Base Width, ft 0.0006 1.5 2.0 2.5 3.0 3.5 4.0 4.5 Depth, ft
Main Stem: Hoosic River
HOOSIC RIVER SYSTEM, NORTH ADAMS PREDICTED WIDTHS, FT* MAIN STEM SOUTH BRANCH NORTH BRANCH Watershed Area, SM 115.8 74.7 41.7 Q2, CFS 3912 1115 2400 Reference Reach Width, FT 100 78 60 VT HGR Width, FT 106 87 67 Sed. Analysis Model, FT 106 61 59 (Cobble) 73 (Sand) *Use Compound Channel for Flood Flows