1986: Water Resources Development Act of 1986: Authorized Construction.
2005: A Limited Reevaluation Report (LRR) completed in 2005 calculated a Benefit to Cost Ratio (BCR) of 0.73 associated with construction of a second Poe-sized lock. The report assumed that current rail infrastructure could handle commodities impacted by an outage of the Poe lock. It also assumed negligible probabilities of failure, based on past performance.
2005: Benefit Cost Ratio Issues:
- Assumption that 100 percent of commodities are delivered
- Rail capacity was assumed as sufficient
- Assumption of major overhaul in 2017
- Probabilities of component failures have increased
- Assumption of new vessels being Mac Lock-Sized
2007: Water Resources Development Act of 2007: Construction at 100 percent federal expense.
2014: The U.S. Army Corps of Engineers conducted a Partial Benefits Analysis to determine if some benefit categories were not captured or insufficient information was used. Partial Benefits Analysis: Expert elicitation held with two dozen stakeholders reliant on Soo Locks to determine how lock closures affect business and what their response would be to a significant lock outage Due to the results of the Partial Benefits Analysis, the U.S. Army Corps of Engineers decided that an Economic Reevaluation was needed.
2018: Economic Validation Study Complete
2018: Water Resources Development Act of 2018: Project authorized.