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Soo Locks project finally underway with 2027 target date for opening

Aerial shot of the Soo Locks

(This week, MI Environment is featuring several articles from the State of the Great Lakes report. Today’s article was written by Larry Karnes (retired) and Elisha Wulff, of the Michigan Department of Transportation.)

After many years of false starts and lack of funding, construction is underway on a new large lock that will provide the necessary capacity and redundancy for Michigan's Soo Locks to continue accommodating marine traffic vital to the North American economy.

The need for a second lock at Sault Ste. Marie to accommodate ships up to 1,000 feet in length has long been identified for the maritime complex, which is a critical component of the entire Great Lakes-St. Lawrence Seaway navigation system. Construction was originally authorized by Congress in 1986. But a lack of Congressional funding and related bureaucratic issues kept the project from moving forward, except for some preliminary construction and continued planning activities.

More than 75 million tons of cargo and 3,000 cargo vessels pass through the locks annually. Owned and operated by the U.S. Army Corps of Engineers, the lock system raises and lowers vessels approximately 21 feet to overcome the difference in elevation between Lake Superior and Lake Huron.

There are two operational locks — the MacArthur and the Poe. The MacArthur was built during World War II and can accommodate vessels up to 730 feet long and 76 feet wide. The Poe was opened in 1968 and can accommodate vessels up to 1,000 feet in length and 105 feet in width. There are two additional locks – the Davis and the Sabin — which were constructed during World War I and are functionally obsolete and permanently closed.

Since the Poe's construction, Great Lakes fleets in the United States and Canada have replaced many of their older vessels with newer, larger vessels, most of which can only use the Poe because of their size. As a result, 89 percent of all the cargo passing though the locks is restricted to using the Poe. This critical dependency on the Poe presents a significant risk not only to Great Lakes shipping, but to the nation's overall economy. Should the Poe become inoperable due to mechanical failures or other causes, impacts will be felt throughout North America.

A U.S. Department of Homeland Security study found that a six-month closure of the Poe would result in a complete shutdown of Great Lakes steel production. This would lead to 75 percent of U.S. integrated steel production ceasing, as well as 80 percent of U.S. iron ore mining. Automobile and transportation equipment production would essentially end in North America, with 11 million jobs lost and a $1.1 trillion decrease in Gross Domestic Product. Every state in the country would be adversely affected.

In 2018, a new economic validation study was completed, which resulted in an updated benefit/cost ratio, allowing the project to move forward toward Congressional funding. Congress reauthorized construction of the new lock in October 2018 with an estimated project cost of $922.4 million (including $32 million spent prior to 2019).

The State of Michigan provided $52 million in December 2018 to help advance the project and allow it to rank more highly among national infrastructure needs. The U.S. Army Corps of Engineers also received $32.4 million in federal funds for fiscal year 2019, and fiscal year 2020 budget included an additional $75.3 million.

The new lock will replace the closed Davis and Sabin locks, but will have the same dimensions as the Poe and will provide much needed redundancy for the aging Poe. The construction project consists of three main phases:

  • Deepening the upstream approach channel (2020-2021).
  • Rebuilding the upstream approach walls (2020-2022).
  • Construction of the lock chamber (2022-2027).

This schedule assumes Congress will continue to provide efficient funding for the project.

Photo credit: MDOT

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