Since 1978 the concept of longitudinal edge drains along iowa primary and interstate highways has been accepted as a cost-effective way of prolonging pavement life. Edge-drain installations have increased over the years, reaching a total of nearly 3, 000 mi by 1989. With so many miles of edge drain installed, the development of a system for inspection and evaluation of the drains became essential. Equipment was purchased to evaluate 4-in.-Diameter and geocomposite edgedrains. Initial evaluations at various sites supported the need fora postconstruction inspection program to ensure that edge-drain installations were in accord with plans and specifications. Informationdisclosed by video inspections in edge drains and in culverts was compiled on videotape to be used as an informative tool for personnelin the design, construction, and maintenance departments. Video evaluations have influenced changes in maintenance, design, and construction inspection for highway drainage systems in iowa. This paper appears in transportation research record no. 1329, Geocomposite pavement drain systems 1991
Abstract