0.6% with a maximum discharge capacity of 360 m³/s. Exceeding this limit puts the bridge under internal pressure and damages the structure in the process. Considering that the Selinus is long, with a median gradient of 2.2% and a drainage basin of , the following median intervals were calculated, depending on the method employed: 250 years (Günerman method) 550 years (D.S.I. method) 1,100 years (Mockus method) 8,500 years (Snyder method) The study came to the conclusion that statistically every 700 years, a value which has been referred to as the "arithmetic mean", floods are to be expected which would exceed the capacity of the bridge. See also List of Roman bridges Roman architecture Roman engineering Notes Sources Further reading External links Roman bridges in Turkey Deck arch bridges Stone bridges in Turkey Pergamon Bergama Tunnels in Turkey Buildings and structures in İzmir Province Arch bridges in Turkey