Laserfiche WebLink
<br /> <br />,. <br /> <br /> <br />N <br />(,('.:l <br />l\:I <br />... <br /> <br />Roadbank Erosion <br />Latera 1 <br />Recession <br />Rate Category <br />(ft/yr) <br /> <br />0.01-0.05 Slight <br /> <br />0.06-0.15 <br /> <br />0.16-0.30 <br /> <br />0.30+ <br /> <br />Mode ra te <br /> <br />Seyere <br /> <br />Very Severe <br /> <br />What recession rates mean: <br /> <br /> <br />Description <br /> <br />Some bare roadbank but actiye erosion is not <br />readily apparent. Some rills but no vegetative <br />overhang. Ditch bottom is grass or noneroding. <br /> <br />Roadbank is bare with obvious rills and some <br />yegetative overhang. Minor erosion or <br />sedimentation in ditch bottom. <br /> <br />Roadbank is bare with rills approaching one foot <br />in depth. Some gull ies and overhanging <br />yegetation. Actiye erosion or sedimentat;on in <br />ditch bottom. Some fenceposts, tree roo' " or <br />culyerts eroding out. <br /> <br />Roadbank is bare with gullies, washouts, and <br />slips. Severe vegetatiye overhang; fenceposts, <br />powerlines. trees and culyerts eroded out. <br />Active erosion or sedimentation in ditch bottom. <br /> <br />at 0.01 feet/year and 90 pcf : 20 tons/acre/year <br />at 0.05 feet/year and 90 pcf : 100 tons/acre/year <br />visible rills on the bank : 12 tons/acre/year <br /> <br />21 <br />