Methods of estimating scour at bridges and abutments based on recommendations in the fhwa 1988 technical advisory on scour are presented. Estimating abutment scour is discussed based on specific recommendations in fhwa's publication hec-18. Additionally, research results on pressure flow developed at colorado state university by lila abed, and on the effect of wide footings on scour depths developed at the turner fairbank hydraulics laboratory by sterling jones are presented. Also discussed are the effect of angle of attack on shape factor of a pier and on rows of columns and the top width of scour holes. Knowledge of the top width of scour holes is important in determining if scour at piers and abutments are independent of each other, and for designing riprap protection. This paper appears in transportation research record no. 1290, Third bridge engineering conference, march 10-13, 1991, denver, colorado, volume 2.
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