The ANSI/AWWA C150/A21.50 procedure used for calculating truck loads on buried Ductile Iron pipe, which is based on the teachings of Spangler and others, employs the same methods used in ANSI A21.1, the older design standard for Cast Iron pipe. The approach for calculating truck loading is adequate at any depth of cover. However, depths of cover less than 2.5 feet are generally not recommended under roads and highways due to the possibility of high dynamic loading. When 2.5 feet or more of cover cannot be provided, the procedure in ANSI/AWWA C150/A21.50 can still be applied. However, if impact factors higher than 1.5, which is incorporated in the standard, are anticipated, then such impact factors should be employed. Further, in those shallow covers, maintenance of the road surface over the pipe may be more of a concern than serviceability of the pipe.