A few months back DOE themselves listed some 800 dams east of the Mississippi that could be retrofitted to return to electricity production.
Unfortunately wind fixated “greenies” want to tear out all the dams and let the rivers flow free. Never mind that hydro is tried and true effective green energy production that actually works every day all day. (not to mention not needing to be replaced every 20 years at most)
There is a big fight here in NH about bringing Hydro power down from Quebec. As you pointed out the St. Lawrence seaway flows 24/7 out of the Great Lakes. However, all the people in the northern tip of NH do not want the towers in their back yard. In the southern 2/3 of the state it will travel on existing right of ways. The big fight is that we do not need the power here in NH. We have plenty of capacity right now. What people do not take into account is the fact that the Seabrook Nuclear Plant will not produce power forever. It was built in the 1980’s. Hydro electricity is the cheapest electric power that you can generate. It also produces no greenhouse gases.
A friend works for a company that is associated with wind energy. That company has been buying up shuttered power plants. I find that interesting. Maybe they see the future is going back to the past?