E9 Rotterdam

Lock E9 at Rotterdam Junction has spent a century getting patched. Its concrete chamber, opened with the Barge Canal in the 1910s, was among the first on the Mohawk to be armored — lined with steel plate over the winter of 1941–42, a fix later repeated at neighboring locks up the valley. Here, at mile 29 with a 15-foot lift, the Erie is pure canalized river: E9 is paired with one of the eight movable “bridge dams” that pool the Mohawk for the boating season and are hauled up each winter so ice and floodwater can pass. The name confuses newcomers — E8 downstream is the “Scotia” lock, and E9 alone carries the Rotterdam title, marking where the canal leaves greater Schenectady and strikes west into the open Mohawk Valley.