The Krumm drains 30.0 km² at the middle Albtrauf southwest of the Fils. Its catchment area has roughly the shape of a parallelogram with a longer diagonal from northeast to southwest of about 10 km, perpendicular to it the maximum width reaches a little over 5 km. Its northwest corner lies on the 684.1 m tall Hohenstaufen (mountain) , the northeastern one on Rechberg at an elevation of 707.9 m above sea level, the southeastern one at an unnamed, 564.6 m tall peak east of the Salacher Kapfhöfe , the southwestern one at the mouth (below 330 m ). The highest point is at the top of the Rechberg.