 Once the river reaches the outskirts of Hull, its course is marked by a series of bridges, most of which open to allow boats to pass. There are swing bridges, lift bridges and bascule bridges, and the river becomes part of the Port of Hull. The river, which is the dividing line between West and East Hull, bisects the city's industrial area. The bridges can cause ship traffic delays during high tides, though river traffic is less than it once was. The Beverley and Barmston Drain rejoins the river above Scott Street Bridge. Below North Bridge, an unused dry dock on the west bank marks the former entrance to Queens Dock. Below Drypool Bridge, a muddy basin on the east bank was once the entrance to Drypool Basin and Victoria Dock. The river reaches its confluence with the Humber estuary in the centre of Kingston upon Hull. At its mouth, a tidal barrier has been constructed to prevent tidal surges from entering the river. In the past, these had regularly flooded the town and the flat countryside to the north.
