A method for adjusting values of Manning's roughness coefficient for flooded urban areas

H. R. Hejl

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USGS · 70162873

A method for adjusting values of Manning's roughness coefficient for flooded urban areas

H. R. Hejl

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Abstract

A method is presented for adjusting values of Manning's roughness coefficient for flooded urban areas on the basis of the density of buildings on a flood plain and verified roughness coefficients for natural conditions. An urban roughness coefficient can be calculated to emulate the water-surface profiles to within 0.06 meter for depths of flow less than 0.6 meter and plus or minus 10 percent for depths between 0.6 and 2 meters.

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H. R. Hejl. 1977. A method for adjusting values of Manning's roughness coefficient for flooded urban areas. https://pubs.usgs.gov/publication/70162873

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