Taking up the street sounds like a great idea!
Did your area get less rain this year? A lot of tree canopies are fed by the roots just below them so something has changed or the tree finally got to a point where that small amount of water is no longer adequate. Maybe put the hose on that side on a very slow drip.
Don't seal the pruning cuts. It has been shown the sealer causes more damage than it is meant to keep from happening.
https://extension.unh.edu/blog....
