Whilst the two rivers of York have historically provided benefits for the city they have also caused problems. Standing on the Blue Bridge looking back towards the city, you will see the Foss Barrier. This intriguing structure, built after the floods of 1979 and 1982, supports a large gate used to protect the city when the river rises to a certain height. If the river does rise the gate is released and blocks the River Foss, preventing the river from flowing back on itself and saving nearby homes and businesses from flooding. The water from the River Foss is pumped around the gate and discharges into the River Ouse through a large outflow that can be seen to the left of the gate.