It's a great question, and thank you for it.
There are really two main mechanisms where that work happens, the first being the Boundary Waters Treaty from 1909.
More recently, the Great Lakes Water Quality Agreement from 1972 is really the framework that brings both federal governments together alongside Ontario and Quebec, the eight Great Lakes states, first nations and many others to look at how we are trying not only to restore the Great Lakes from past challenges we've seen from industrial development and urban development but to protect the Great Lakes for future generations.
It's important to say that over the last 50 years there has been tremendous progress. Albeit slow, it's been positive and in the right direction, but there's certainly more that we need to do.