I think they really mean it this time
Washington State highway 501 (south end) is being progressively eroded by the Columbia River; the state piled these jersey barriers up at the end of the (ped/bike; cars are stopped a mile south) road to let people know that, yes, they really don’t want people going any further and falling into the river if they misstep and a section of the road crumbles away with them on it.