Great Lakes Dredging Crisis


The dredging crisis on the Great Lakes is not a recent development. Federal funding for maintaining the system has been inadequate for decades. High water levels in the 1990s masked the effects of inadequate dredging, but Lake levels fell to near record lows by the end of the 20th century. After a period of slight recovery, water levels fell to new record lows on Lakes Michigan and Huron at the end of 2012 and remain well below long term average on all five Great Lakes.

Water levels fluctuate and are determined by precipitation and evaporation. Lack of adequate investment in dredging, on the other hand, is a man-made malady. It is estimated the U.S. Army Corps of Engineers needs more than $200 million to restore Great Lakes ports and waterways to project dimensions.

When Congress authorizes a Federal harbor or waterway, it specifies the project's dimensions. The channels will be dredged to a certain width and depth. Once construction is complete, it is the U.S. Army Corps of Engineers' responsibility to maintain those project dimensions. However, since funding for dredging has been woefully inadequate for so long, more than 18 million cubic yards of sediment now clog the system.

dredging_crisis_piechart2Funding of Operation and Maintenance ("O&M") dredging comes from the Harbor Maintenance Trust Fund ("HMTF"), which receives its funds from a tax on cargo movement. As of this writing, the HMTF has a surplus of almost $7 billion. The $200 or so million needed to restore the Great Lakes system to project dimensions is available. The Administration need only request the funds when it proposes its budget. Instead, the Lakes dredging appropriation remains mired in the $20-30 million range.

Another problem facing the Lakes is the way in which Federal dredging dollars are shared among the nation's waterways. In one recent Federal budget, the Ohio River system's Federal dredging budget appropriation equated to $1.10 per ton of cargo handled. In comparison, the Lakes received the equivalent of $0.52 per ton of cargo.

Lack of Draft Negates Efficiencies of Waterborne Commerce

When lack of adequate dredging reduces the depth in a harbor or waterway, vessels must reduce the amount of cargo they can load. In the maritime industry, this is known as "light loading." The amount of cargo that must be forfeited varies depending on the size of the vessel. For U.S.-flag Lakers, just one inch of reduced draft trims anywhere from 50 to 270 tons of cargo from their payload. An ocean-going vessel sacrifices 115 tons of cargo for each inch of lost draft.

Impact of Dredging Crisis on Major Great Lakes Vessel Classes

Major Great Lakes Vessel Classes Vessel Length (feet) Per-Trip Carrying Capacity Capacity Per Inch Of Draft*
1,000 69,664 267
806 34,720 146
767 28,336 127
730 27,558 115
635 22,064 107
501 13,776 71

*Capacity per inch of draft reflects the incremental tonnage carried at normal loaded draft

Unfortunately, the loss of draft is mostly measured in feet rather than inches. By the end of 2012, vessels loading cargo at Lake Superior ports were leaving as much as 10,000 tons of cargo behind each trip because of lack of adequate dredging in either the connecting channels (St. Marys, St. Clair, and Detroit Rivers) or the discharge port.

What does 10,000 tons mean to the economy?

  • 10,000 tons of iron ore produces enough steel to make 8,300 cars.
  • 10,000 tons of coal produces enough electricity to power a metropolitan area of the size of Greater Detroit for more than 3 hours.
  • 10,000 tons of limestone provides the aggregate needed to build 25 average American homes.

There are other impacts to light loading. Since the vessel's carrying capacity is not being fully utilized, the operator cannot offer the best freight rate. The customer is not able to receive or ship all the cargo it needs. Shortfalls in raw materials then translate into less production at the nation's factories and fewer opportunities for employment.

Lack of Dredging Can Close a Port

Dunkirk, New York, is a tragic example of how lack of adequate dredging can so reduce a port's viability that it will reach the point where waterborne commerce is no longer feasible. The power plant in Dunkirk used to receive more than 500,000 tons of coal in U.S.-flag Lakers each year. However, shoaling in the harbor became so severe that the coal trade to Dunkirk ceased on November 9, 2005 with the delivery of a mere 6,820 net tons. That cargo represented only 49 percent of the vessel's rated capacity. Coal now must be railed to Dunkirk. The increase in freight rates is not the only negative development. Trains use more fuel and produce more emissions than ships. In reality, the dredging crisis has victimized the environment in western New York.

In recent years, the ports of St. Joseph, Michigan, and Waukegan, Illinois, have been effectively closed for inadequate depth in the harbor. The final coal cargo of 2011 destined for Holland, Michigan, had to be cancelled because of shoaling in the navigation channel.

Vessels Greenest Form of Transportation

The dredging crisis also has environmental impacts. Vessels are the greenest form of transportation. They use less fuel and produce fewer emissions than trains or trucks. For example, a study, Great Lakes and St. Lawrence River Commerce: Safety, Energy and Environmental Impacts of Modal Shifts, found that if 25 million tons of cargo switched to rail, trains would burn an additional 14 million gallons of fuel and generate another 4,321 tons of emissions. If certain commodities moved by truck, fuel consumption would increase by 3.4 million gallons and emissions would grow another 570 tons.

As the graphic below further illustrates, just one vessel keeps hundreds of trains and thousands of trucks off our congested rail beds and highways.


What Can Be Done?

In fairness, the nation has neglected its infrastructure in general for decades. However, as noted, the Great Lakes have fared worse than other waterways. The Administration must view the Lakes as a system rather than as individual ports. When the impacts of shipping are computed on a Lakes-wide basis rather than individual ports, there will be a corresponding increase in funding for the system.

Such a course change will likely take time. In the interim, the Great Lakes delegation must fight to bring home more Federal dredging dollars. The raw materials that move on the Great Lakes are the building blocks of our economy, national defense capabilities, and standard of living. It's no accident that 70 percent of the nation's steelmaking capacity is based in the Great Lakes basin; that 50 percent of our cars are manufactured in Great Lakes states; and that more than half of all heavy manufacturing takes place in states that border the Lakes. With cargo moving topping 200 million tons per year, the Great Lakes are one of the foundations of America's transportation system and must be maintained to allow for maximum efficiency.