A Watershed Approach to Dam Removal and Dam Management in the Connecticut River Basin

2016 Maine Sustainability & Water Conference The Connecticut River Watershed – by the numbers

410 mile mainstem and 20,000 miles of streams in watershed 70% of the freshwater input to Long Island Sound 7.2 million acres Population of 2.3 in more than 300 towns Drinking water source for 4.3 million people A Century of Dam Building Collapse of a Fishery A river’s flow is about more than just volume…

Same volume! Connecticut River natural flow regime Most dammed watershed in North America

Large Dams Small Dams 70 Large Dams

• Hydropower

• Flood Control

• Water Supply

• Recreation

• 70 Large Reservoirs

• 143 Ecological points of interest

• 320+ inflow hydrographs

• 362 River Reaches

The Optimization Challenge

•Find daily releases at 70 reservoirs

•Meet flood control, hydropower, water supply, recreation and ecosystem requirements

•Solve problem over long time periods (a season, a year, multiple years)

Flow Prescription - Mussels

Who Mussels What No change to monthly Q99 or lower flows; minimal change (<10%) to annual Q90 When April - October Where Multiple mainstem and tributary locations (see distribution map) Why/How Adequate low flows needed to inundate mussel beds, ensure

recruitment, dissolved O2, minimal current, surface flow connectivity Relicensed Hydropower Projects

Wilder Dam, Connecticut River, VT/NH Bellows Falls, Connecticut River, VT/NH Photo: Katie Kennedy Photo: Dan Axtell/danaxtell.com

Vernon, Connecticut River, VT/NH Bellows Falls bypassed reach, Connecticut River, VT/NH Photo: TransCanada Photo: Katie Kennedy 2,730 Small Dams NeCAT – A Tool for Evaluating Fragmentation

Help states to move from opportunistic to “ecological-benefits” approach to dam removal / fish passage improvement

Produce a tiered list of dams in the Northeast U.S. based on their potential ecological benefit if removed / improved passage

A tool that allows managers to re-rank dams at multiple scales (state, HUC, etc) or using attribute filters (river size class, dam type, etc) Where are the longest unfragmented networks between all dams?

Distribution of 10 Longest Networks:

Lengths: Length Watershed(s) 761.4 Mainstem, Williams, Black, White Class Frequency 386.2 Mainstem, West 1 (0-10mi) 2297 292.3 Mainstem, Scantic, Farmington, 2 (10-25) 145 Mattabesset, Eightmile, Salmon, 3 (25-50) 47 Hockanum

4 (50-100) 27 217 Mainstem, Fort, Deerfield, Mill/Manhan, Mill/Amherst, 5 (100-250) 9 Roaring Brook 6 (250-500) 3 192.8 Mainstem, Ompompanoosuc

169.1 Westfield

155.8 Chicopee

112.4 Mainstem

104.1 Ottauquechee What dam removals would yield the longest absolute growth in connected habitat?

VT209 Absolute Gain: 96 Miles Total Length: 470 Miles Relative Ratio: .21

Absolute Gain: Top 10 Minimum Total Length in Ratio: Absolute Major Tributary Name River Name River Size Dam ID Length in Miles If Relative Gain Additional Miles of Up Reconnected in Length Length or Down Network 1 West West River 3 VT_209 96.31 469.80 0.21 2 West West River 2 VT_105.01 89.66 185.98 0.48 3 White Third Branch White River 2 VT_21.01 81.50 344.88 0.24 4 Mainstem Connecticut River 4 CT_4913 77.96 370.27 0.21 5 Chicopee Quaboag River 2 MA00902 74.74 155.32 0.48 6 Waits Waits River 2 VT_24.01 73.52 261.62 0.28 7 Westfield Westfield River 2 MA00969 72.87 241.93 0.30 8 Westfield Westfield River 3 MA00611 68.78 146.75 0.47 9 Roaring Brook Mill River 2 MA00493 55.14 272.17 0.20 10 Mainstem Connecticut River 3 VT_22.06 47.74 151.17 0.32 6 Elements to Advance Dam Removal

Project Regulations Dam Safety Managers

Funding Leadership Momentum Project Regulations Dam Safety Managers

Funding Leadership Momentum A Programmatic Approach to Dam Removals

CT River States 1995 - 2005 – 7 removals 2006 - 2016 – 20 removals

PA – 23 removals in 2015, highest number of removals for 13th year in a row Common Themes • People • Science • Regulation • Opportunity