Problem: Erosion gully on crest and upstream or downstream slope Possible causes Heavy rainfall. Poor grading and improper drainage of crest. Improper drainage causes surface runoff to collect and drain off crest at low point in upsteam or downstream shoulder. Harm Can reduce available freeboard. Reduces cross-sectional area of levee. If allowed to continue, can lead to severe deterioration of slope and shorter internal drainage path. Action required Protect eroded areas with graded rock or clay. Re-grade crest to provide proper drainage of surface runoff. Re-establish protective
Problem: Erosion gully on crest and upstream or downstream slope Possible causes Heavy rainfall. Poor grading and improper drainage of crest. Improper drainage causes surface runoff to collect and drain off crest at low point in upsteam or downstream shoulder. Harm Can reduce available freeboard. Reduces cross-sectional area of levee. If allowed to continue, can lead to severe deterioration of slope and shorter internal drainage path. Action required Protect eroded areas with graded rock or clay. Re-grade crest to provide proper drainage of surface runoff. Re-establish protective
DEP-8419-Levee-design-construction-and-management-guidelines_FA_web-VBrev-150310.docx