The normal depth of scour for alluvial rivers is determined by Lacey’s formula
1
\(\sqrt {0.475} \left( {\frac{f}{Q}} \right)\)
2
\(0.475{\left( {\frac{Q}{f}} \right)^{\frac{1}{3}}}\)
3
\({0.475^3}\sqrt {\frac{f}{Q}} \)
4
\({0.475^3}\sqrt {\frac{Q}{f}} \)