That's too bad, and not a little odd the operator was not even sounding a horn in the event of main power or control failure. i wonder if it was one of those or if the operator had collapsed?
edit: It does look like the bridge was manned and I think...forward propulsion uninterrupted.
As has been reported by former residents, that video event is similar to the way year-round Cuttyhunkers tend to stop there old plateless, brakeless beater cars and golf carts on the hills of their tiny MA island in the off season. Just turn towards one of the old stone walls and come to an effective if noisy abrupt halt. If fortune smiles, no liquid is spilled.