Wyoming Silver Jackets River Ice Workshop Ice Jam Mitigation
CRREL Ice Engineering Group
Presented by, Joseph Rocks Research Hydraulic Engineer ERDC Cold Regions Research and Engineering Laboratory, Hanover NH May 2018 Ice Jam Mitigation
. Objectives . Advance/Early Warning Measures . Emergency Measures . Permanent Measures
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Mitigation Objectives
. Reduce ice jam flood damages . Reliable performance . Low environmental impact
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Freezeup Jam Mitigation Objectives ► gradual production and accumulation • reduce production • collect ice in safe place
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Breakup Jam Mitigation Objectives
► dynamic breakup and jam • reduce ice volume • arrest run in safe place • allow run to pass
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures
. Goals: Flood protection Reduce ice supply Control breakup sequence Increase conveyance . Non-structural intervention . Two weeks to six months lead time . Can be inexpensive . Effectiveness difficult to quantify
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Early Warning
. Ice motion detectors . Trained observers . Web Cameras . Provides critical information . Two weeks to six months lead time . Inexpensive and invaluable
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Early Warning
Ice Motion Detectors . Trip wires in ice ► alarms inform emergency managers ► select locations to give as much lead time as possible
A CRREL ice jam motion detector installed on the Kennebec River in Maine.
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Early Warning
Trained Observers . Part of emergency response team . Track pre-event ice conditions . Check upstream & downstream during event . Helpful for after-action assessment, permanent measures
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Early Warning Web Cameras
Web Camera Images of Lamoille River Upstream of Hardwick, VT
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Mechanical Weakening
. Weaken ice to pass ice run . Mechanical & thermal methods . 2-6 weeks before breakup . Very low cost . Effectiveness difficult to quantify . Ice cutting/hole drilling ► 4WD trencher or auger ► amphibious ice saw . Ice breaking ► amphibious excavator ► vessels
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Mechanical Weakening Hole Drilling . Oconto River, WI ► 10 ft grid, central 2/3 of channel ► holes expand to weaken sheet ► ice moves into Lake Michigan
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Mechanical Weakening
Ice Cutting and trenching Herringbone pattern used on Beaurivage River, Quebec
• Slot patterns cut in sheet ice to encourage ice to release and move downstream without jamming.
• Effective at many locations.
Ice cutting experiment at Montpelier, VT
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Mechanical Weakening Ice Breaking
Icebreakers / towboat to break downstream ice cover in Large hovercraft creates a wave to break advance of natural breakup or clear channels through jams. thick ice over 3-ft-thick
Amphibex floating backhoe, effective but slower. Work from downstream to upstream. Need sufficient current needed to convey ice pieces downstream
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Thermal Weakening
. Accelerate natural ice deterioration . Effectiveness difficult to quantify . Dependent on meteorological conditions, sun angle, hours of daylight . Dusting ► Acceptable material may be difficult to identify ► Application methods include aerial, hydroseeder, other surface method . Warm water source ► Warm water is the major cause of jam erosion
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Advance Measures: Thermal Weakening
Dusting on the Platte River
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Emergency Measures
. Goals: Flood protection Increase conveyance Remove ice Jam in place . Cost & effectiveness depend on timing . Excavation . Blasting . Flood Fighting . Do nothing
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Emergency Measures: Excavation
Excavation - Stage Rising . Immediate flood threat . Pre-positioned equipment ► excavator, clam-shell, bulldozer ► clear channel D/S of toe ► dislodge key pieces at toe . Can be inexpensive (& nerve wracking)
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Emergency Measures: Excavation
Excavation - Stage Falling . Second flood threat possible . Bulldozer clears channel ► from D/S, through toe . Dislodge key pieces ► blasting, clam-shell . Expensive to excavate and remove ice pieces . Access often difficult
BUILDING STRONG® Innovative solutions for a safer, better world Excavation Examples
. Gorham, NH
. Morrisonville, NY
BUILDING STRONG® Innovative solutions for a safer, better world Emergency diversion channel: Lancaster, NH
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Emergency Measures: Blasting
. Open water downstream, work up from toe . Most effective charges placed under ice . Pre-planning needed . Not suitable for urban area
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Emergency Measures: Flood Fighting
. Track upstream conditions (observers) . Check database, local accounts to identify potential flood areas . Sandbags (unfrozen sand) . Temporary dikes . Evacuation plans (!) . Combine with ice removal
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Emergency Measures: Do Nothing . Thin, weak ice . Little remaining ice supply . Forecast for mild temperatures & no rain . Late season jam (check records) . Other constraints
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures
. Goals: Flood protection Reduce ice supply Increase conveyance Control breakup sequence Displace jam location . Structural solutions . 2-5 year lead time . Expect high benefits and reliability . Generally costly although some low-cost solutions under development
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures
Permanent Ice Control Measures . Flow control . Ice control structures (ICS’s) . Diversion channels . Thermal discharge . Levees, floodwalls . Floodproofing . Land management
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Flow Control
Early Winter . Control flow to promote stable ice cover formation and maintain cover in place . Flow cutbacks for ice formation at hydroelectric projects. ► The goal is to form an ice cover by the juxtaposition of arriving frazil pans and floes. . Early winter flow regulation to control freezeup ice jam flooding
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Flow Control
Mid-Winter . Limiting the magnitude and rate of flow changes at the dam can preserve a river ice cover. . The winter pool level at water storage reservoirs can influence the location and severity of freezeup ice jams on tributary rivers and streams.
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Flow Control
Breakup Period . Regulate pool level to move location of ice jam initiation point upstream or downstream. . Flow regulation can influence the timing of the final breakup on rivers . Operators of river dams may have to pass the ice and flood wave as it arrives to avoid a number of problems. ► Ice grounding in pool ► Thick ice buildups against dam gates ► May not be able to pass ice once flood wave passes
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Ice Control Structures Freezeup ICS - Ice Boom & Weirs
. Collect ice at a safe upstream location . Reduce ice supply to downstream problem area . Requires: ► low velocity <= about 2.3 ft/s ► adequate upstream ice storage capacity . If properly sited and designed booms are reliable & low cost . Annual installation and removal time and cost, wear and tear, debris management need to be considered
BUILDING STRONG® Innovative solutions for a safer, better world Oil City, PA ICS
BUILDING STRONG® Innovative solutions for a safer, better world Oil City, Boom Deployed
Oil City, Boom stored
BUILDING STRONG® Innovative solutions for a safer, better world Ice Control Weirs
. Same design objectives as booms: retain a freezeup ice accumulation at desirable upstream location to reduce the ice supply to the downstream problem area. . Success stories include Oil City, PA and Lancaster, NH, where weirs designed as freezeup ICS also retain the breakup ice run.
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Ice Control Structures
Breakup ICS . Retain ice cover throughout breakup, or . Arrest ice run in safe location . Allow flow through or around ice accumulation to decrease stages
BUILDING STRONG® Innovative solutions for a safer, better world Cherryfield, Me Breakup ICS
The dam was constructed in 1961 by the Corps for the purpose of reducing flood damage caused by ice jams.
BUILDING STRONG® Innovative solutions for a safer, better world Breakup ICS - Weir with Piers
. Ste. Anne River, Quebec ► weir with piers ► hold sheet, store ice run in pool ► all flow over weir
BUILDING STRONG® Innovative solutions for a safer, better world Breakup ICS - Piers
. Credit River, Ontario (1988) ► closely spaced piers ► in-channel & floodplain ice storage
BUILDING STRONG® Innovative solutions for a safer, better world Ice Control Structures - Cazenovia Creek, Buffalo, NY
BUILDING STRONG® Innovative solutions for a safer, better world CAZENOVIA CREEK, ICE CONTROL STRUCTURE (ICS) - WEST SENECA, NY
Excessive Debris Build-up
BUILDING STRONG® Innovative solutions for a safer, better world Ice Control Structures – Lamoille River, Hardwick, VT
BUILDING STRONG® Innovative solutions for a safer, better world BUILDING STRONG® Innovative solutions for a safer, better world BUILDING STRONG® Innovative solutions for a safer, better world BUILDING STRONG® Innovative solutions for a safer, better world Ice Control Structures – Salmon River, CT
BUILDING STRONG® Innovative solutions for a safer, better world Ice Control Research at CRREL
Physical model study of ICS with in-channel relief flow for sites where floodplain bypass flow unavailable. Sponsored by Alcoa.
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Thermal Discharge
. Kankakee River (1987) ► siphon warm water from cooling pond ► reduces ice volume, breakup run moves D/S
BUILDING STRONG® Innovative solutions for a safer, better world Ice Jam Mitigation Permanent Measures: Thermal Discharge . Other Sources ► waste-water treatment plant ► ground water ► deep water from lakes & reservoirs ► inexpensive if already available
At Montpelier, VT, 46 deg F STP effluent pumped into Winooski to help open a lead in the downstream end of the 2007 freezeup ice jam.
BUILDING STRONG® Innovative solutions for a safer, better world Conclusions
. The Corps has designed 7 ICS in CONUS . Buffalo, New England, Pittsburgh Districts . ICS Design is not “cook book” yet . Good idea for sites that repeatedly experience ice jam flooding
BUILDING STRONG® Innovative solutions for a safer, better world Conclusions . Lead time = effectiveness ► Emergency measures last resort ► Early warning and coordination invaluable ► Higher risk/uncertainty with advance measures
. Cost-effective ice control technology improving ► Freezeup and breakup ICS ► Reliable performance possible ► Range of application expanding
BUILDING STRONG® Innovative solutions for a safer, better world Questions?
BUILDING STRONG® Innovative solutions for a safer, better world