The map shows the frequency of bedload transport events during 2006, given in percent. Strong tidal currents in the Southern Bight and along the English, Dutch and German coasts generate high frequencies of bedload transport. On Dogger Bank the frequency of bedload is also increased, but here bedload is produced by waves. This is also true for Horns Rev at the Danish coast. North of Dogger Bank bedload is infrequent because tidal currents are weak and because the water is so deep that surface water waves hardly reach the bottom.