Big Lake Floodway Ditch, Arkansas
St. Francis & Mississippi
Establish baseline and develop topography to depict scour holes downstream of the Highway 77 Bridge, Big Lake Floodway Ditch. Locate a baseline 100 ft. southeast of the southeasterly top of bank. Set iron rods at 100 ft. intervals along the baseline beginning at the baseline and extending 100 ft. past the waters edge on the northwesterly top of bank and at the upstream and downstream face of the bridge. Cross-section at the centerline of the bridge and downstream face at 50 ft. intervals to 100 ft. past the northwesterly top of bank.