|Beschreibung:||The bedforms and equivalent roughness sizes in tidal channels of the Central Dithmarschen Bight on the basis of field measurements and numerical modeling are studied. Side scan sonar and echo sounder were employed to acquire bedform dimensions, while acoustic profilers were used to measure current velocities. The equivalent roughness size is estimated on the basis of best fit line of velocities in the bottom boundary layer. The obtained bedform dimensions and flow conditions are used to check existing equations for estimation of bedform dimensions and equivalent roughness sizes. Numerical model simulations are also carried out in conjunction with modified equations to develop maps of bedforms and equivalent roughness sizes in the study area. In general, the empirical equations are able to predict bedform dimensions and equivalent roughness sizes in shallow areas.