The NCHRP panel for Project 1-34 identified the need for an independent review of that project's findings, and, ultimately, for additional work to test those findings through condition studies of subsurface drainage features in selected HMA and PCC pavement sections.

The objectives of this project were to (1) critically review the final report and supporting information developed in Project 1-34 and (2) develop an experimental plan to evaluate and test key findings from that report.

Selected portions of the final report for this project were published as Research Results Digest 268 along with selected portions of the final report for Project 1-34. the experimental plan was executed in Projects 1-34C and 1-34D.