An engineered solution to low water levels in the middle Great Lakes is going to cost much much more than has been publicly discussed. Whether the solution is a structure in the St. Clair River, or less probably in the Niagara River, we would still have to come up with a great deal of money to mitigate the impacts of changing water levels on the St. Lawrence River: for structures to restrict the flow; maintain adequate depths for navigation and environmental purposes; and for excavation to prevent flooding. We might need $120 billion to cover these costs, which is why some researchers have dismissed such a project out of hand.

Costs should tell us two things: what we might have to forego in order to do something and whether a project is worth doing at all.

The Upper Great Lakes Study Board wasn’t asked to look closely at mitigation for water bodies downstream of the St. Clair River, when it addressed the water level problem  in the middle Great Lakes, but it did review the literature, most pertinently the (1993) Levels Reference Study—Great Lakes St. Lawrence Basin. The Study Board’s review can be found in its final report, Chapter 8.6.3, “Lower St. Lawrence River Mitigative Requirements.”

The scary $120 billion mentioned above would cover the costs of addressing the adverse conditions associated with relatively extreme scenarios in the lower St. Lawrence; it would facilitate the all-important buy-in of those downstream for the regulation of water levels upstream.

“Measures to improve conditions in the lower St. Lawrence River would be required to gain system-wide political support for multi-lake regulation. …The Levels Reference Study found that improving conditions over the basis of comparison [simulated historical conditions] would be too expensive, with the costs of required excavation alone exceeding $120 billion.”

Having found this bar too high, the Levels Reference Study went on to look at the costs associated with mitigating any impacts on the St. Lawrence as a result of  the proposed regulation. These came in at between approximately $3.5 and $5.1 billion for excavation alone. The additional combined cost of control structures at all locations was about $400 to $900 million, depending on the design.”

The range of water levels  the Study Board looked at in 2012 as part of examining multi-lake regulation exceeded the  range the Levels Reference Study had looked at in 1993. So understandably the Study Board came up with higher costs for mitigation than had the earlier report.

The Study Board concludes its chapter by saying, “the costs to provide such mitigation could be greater than the costs of the combined structures and excavation required on the St. Clair and Niagara Rivers for the multi-lake plans reviewed.  Therefore, multi-lake regulation should not be studied again unless consideration is given to the requirements in both the lower St. Lawrence River and the upper Great Lakes.”

Note: whether an engineered solution to raise water levels falls under the rubric of water restoration (that the IJC recommended) or multi-lake regulation, (system-wide solutions that the IJC rejected) the same claim for mitigation could be made by the St. Lawrence River.

The International Upper Great Lakes Study: Lake Superior Regulation: Addressing Uncertainty in Upper Great Lakes Water Levels, March 2012 http://www.ijc.org/files/publications/Lake_Superior_Regulation_Full_Report.pdf

In my next water levels blog: Restoration versus Multi-lake Regulation: Why Getting Them Mixed Up isn’t Helping the Water Levels Debate.