Managing Ice Jams

MarineLink.com
Wednesday, April 09, 2014
Photo: Karen Watson, U.S. Geological Survey

April showers may bring May flowers, but spring can also bring ice jams to the thawing rivers and streams across the northern United States.

An ice jam or ice dam, is a buildup of broken ice in the river system. It can be a problem that causes the water to back up over the top of highway bridges, roads, or into cities. At times, they can cause flooding. Ice jams can be large–backing up water for miles, or small and only back up water in a small area locally.

An ice jam can damage bridges with the amount of water pushing on the jam from behind; it can force the ice to push the bridge – moving it slightly.

USGS monitors ice jams across the north using cameras as well as by collecting ice thickness information when technicians do regular streamgage work or when measuring discharge on the rivers in the spring.

For example, each year, the Maine Emergency Management Agency and U.S. Coast Guard asks the USGS to measure the ice thickness and provide an ice jam flood potential on the Kennebec River. The U.S. Coast Guard has used their ice breakers to clear the ice in the lower Kennebec River in years when the ice jam flood potential was high.

Greg Stewart, data section chief for the USGS New England Water Science Center, said its part of the agency’s job to monitor river flows throughout the state of Maine and to measure the stream flow underneath the ice.

USGS technicians take ice cores to measure ice thickness at various places on the rivers. In order to make an ice measurement, it’s necessary to drill between 25-30 holes in the ice. Then, thickness is recorded at just several of the holes to help document the measurement conditions.

That information allows the USGS to assess the risk of ice jams, flooding or other problems when the ice begins to melt, Stewart said. According to Stewart, when ice jam flooding starts to happen, there is very little time and very little warning.

Thickness of the ice and how fast a melt occurs affects the ice jam flooding potential. For example while the weather is cold, and the water is freezing you have ice accumulation. When the weather changes and it starts to warm the ice begins to melt and begins to break up. A quick warmup with the ice strong and still in place can cause significant ice jam flooding.

Another sign of spring is the melting snowpack, which is the result of accumulated layers of snow with generally more at high altitudes. Snowpacks feed rivers and streams providing an aquatic life habitat, hydro power, a possible source of drinking water, but they are also a potential flood hazard.

With a quick warm up of high temperatures over a short period of time, there is an increased likelihood of flooding from snowpack melt, but when you have a gradual increase in spring temperatures with moderate temperatures during the day and slightly below freezing at night the flooding potential is decreased slowly and safely.

According to Stewart, when the snowpack starts to melt historically March, that’s when snowmelt driven runoff begins, the USGS looks at the flooding potential.

usgs.gov
 

  • Photo: Iowa Water Science Center, U.S. Geological Survey

    Photo: Iowa Water Science Center, U.S. Geological Survey


Navigation

iNavX Debuts IN-APP Charts, Maps Purchase Capability

iNavX, the benchmark marine navigation mobile application, in partnership with Fugawi X-Traverse, today launched its chart and map in-app purchase program. Now

Big Tankers' Need for Retrofit Slows Use of New Panama Canal

The promise that some oil traders and brokers saw for an expanded Panama Canal to become a new route for large tankers will take longer to realize than expected

MN100: Baker, Lyman & Co., Inc.

The Company: A wheelhouse favorite for generations, Baker, Lyman & Co. is the oldest NOAA & Admiralty Chart Agent in the United States. Baker Lyman has been provisioning vessels with nautical charts,

Environmental

Fednav Welcomes Innovative Ballast System at Indiana Port

Fednav Limited, the largest international bulk shipowner in Canada, welcomed to the Port of Indiana-Burns Harbor, the Federal Caribou, one of seven new oceangoing

2015 Congestion Affected Long Beach Port's Air Quality

Pollution around the Port of Long Beach has been dramatically cut over the last decade, however, according to the latest study, lingering effects from ships at

Global Climate Change Threatens Papahānaumokuākea Marine

Despite its remote location in the Northwestern Hawaiian Islands, Papahānaumokuākea Marine National Monument faces a looming threat of global climate change that

Coast Guard

Philippines: Sea Dispute Won't Shift Ties with China, U.S.

The Philippines' territorial dispute with China over the South China Sea has not caused Manila to rebalance diplomatic ties with either its ally, the United States,

Giant CMA CGM Ship Vasco De Gama Runs Aground

CMA CGM’s mega containership Vasco De Gama ran aground off the Port of Southampton on the UK’s south coast just after midnight on August 22, 2016, reported Fleetmon.

Bollinger Delivers 19th FRC to the USCG

Bollinger Shipyards has delivered the 19th Fast Response Cutter (FRC), USCGC Rollin Fritch, to the U.S. Coast Guard.   The 154-foot patrol craft USCGC Rollin

Maritime Safety

Philippines: Sea Dispute Won't Shift Ties with China, U.S.

The Philippines' territorial dispute with China over the South China Sea has not caused Manila to rebalance diplomatic ties with either its ally, the United States,

MN100: Safety Management Systems, LLC

The Company: A leading US maritime consultancy established in 1996, SMSLLC provides practical risk mitigation solutions for vessel operators and stakeholders.

Giant CMA CGM Ship Vasco De Gama Runs Aground

CMA CGM’s mega containership Vasco De Gama ran aground off the Port of Southampton on the UK’s south coast just after midnight on August 22, 2016, reported Fleetmon.

Government Update

Philippines: Sea Dispute Won't Shift Ties with China, U.S.

The Philippines' territorial dispute with China over the South China Sea has not caused Manila to rebalance diplomatic ties with either its ally, the United States,

Portland Auto Exports Drive ConnectOregon Grant

The Oregon Department of Transportation has awarded a ConnectOregon grant of $2.6 million to the Port of Portland along with tenant Auto Warehousing Co. to fund

TSA Boosts Maritime Security in a Big Way

Though most visible to the general public for its work at America’s airports, the U.S. Transportation Security Administration (TSA) also helps to secure the country’s

 
 
Maritime Careers / Shipboard Positions Maritime Standards Naval Architecture Navigation Port Authority Ship Electronics Ship Repair Ship Simulators Shipbuilding / Vessel Construction Winch
rss | archive | history | articles | privacy | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1998 sec (5 req/sec)