Water coursing into corroded culverts at Jacksonville (Fla.) Naval Air Station was eroding the surrounding soil, causing roads to sink and creating potholes. Infiltration of sand and mud restricted flows, causing backups that flooded parking lots and sometimes buildings. Unwilling to close the heavily traveled roads, the Navy filled and paved over the sink holes to keep traffic moving.Televising of the 6- to 30-inch lines enabled the Navy to assess the problem and budget for repairs. Open trenching would create traffic confusion on the two- to four-lane roads, and compact the soil. The base, along the St. Johns River, has
