Subsurface drainage is known to pavement professionals to be an important factor affecting pavement performance and preservation of public investment. Numerous studies have emphasized the importance of subsurface drainage, yet subsurface drainage is not always considered a critical component when it comes to design, construction, and maintenance of pavement.
The objective of this synthesis is to document the current state of practice by departments of transportation (DOTs) for subsurface drainage in pavement design, construction, and maintenance of highways.
Information to be gathered includes (but is not limited to):
„h Methods used to assess site conditions (e.g. inspection of drainage; structural evaluation of pavement; soil survey)
„h Parameters used to assess drainage needs (e.g. hydrologic information including rainfall data, elevation conditions, roadway geometry); practices for documenting drainage needs and the methods of assessment
„h Drainage features used and their performance
„h Methods for assessing and documenting effectiveness of existing drainage features (e.g., use of rating or ranking systems)
„h Methods used to evaluate influences of subsurface drainage on structural capacity of pavement (e.g. pavement distress, including warping or curling of concrete pavement, base erosion, faulting; bearing capacity of subgrade; pavement roughness)
„h Costs that are tracked related to the design, construction and maintenance of drainage systems
Information will be collected through literature review, a survey of DOTs, and follow-up interviews with selected agencies for the development of case examples. Information gaps and suggestions for research to address those gaps will be identified.
Information Sources (Partial):
First Panel: November 4, 2020 (Virtual)
Teleconference with Consultant: December 11, 2020, 3:00 - 4:00 pm Eastern
Second Panel: July 19, 2021
Ryan Barrett, Kansas Department of Transportation
Xingwei Chen, Louisiana Department of Transportation and Development
Cheryl Clifton, Alabama Department of Transportation
Deepak Maskey, California Department of Transportation
Nusrat Morshed, New Jersey Department of Transportation
Carlton Spirio, GHD
Vivek Tandon, University of Texas, El Paso
Yan Jiang, Federal Highway Administration
Nancy Whiting, Transportation Research Board