, Professor, Bioproducts and Biosystems Engineering
Caleb Arika, Research Associate, Bioproducts and Biosystems Engineering
Subsurface drainage removes excess moisture from the base course and the subgrade of highways, thereby increasing the overall strength of the pavement structure. Previous research has shown conclusively that effective subsurface drainage provides cost-effective benefits in terms of pavement maintenance and replacement costs. There are many factors that must be considered in the design of subsurface drainage systems, and because of the tremendous benefits of subsurface drainage, it is critical to design the drainage system correctly. Several reports have been published nationally that provide guidance to designers of subsurface drainage systems, but these reports are not specific to the conditions of the north central region, nor are they ready guides. The objective of this project was to develop a design and maintenance manual for pavement subsurface drainage systems in Minnesota. The manual is intended for engineers and managers involved in pavement design, construction, and maintenance decisions of Minnesota highways. It provides background information on the benefits of subsurface drainage, methods for evaluating the need for subsurface drainage at a given location, selection of the type of drainage system to use, design of the drainage system, guidelines on how to construct/install the subsurface drainage systems for roads, and instruction on the value of maintenance and how to maintain such drainage systems.