The State of Hawaii Department of Transportation (HDOT) was required by United States Environmental Protection Agency (EPA) Consent Decree to conduct a comprehensive third-party evaluation of their stormwater programs. Over the course of four years, Kennedy Jenks planned and completed an evaluation of HDOT’s six municipal stormwater permits for three HDOT divisions (Airports, Harbors and Highways). The goal of the audit was to identify best practices that could be applied across HDOT’s three divisions to improve overall stormwater program effectiveness. In this presentation, the approach to evaluating HDOT’s stormwater programs will be described including tools and methods that were developed to assist in the audit process. Notable findings to date will be provided, highlighting challenges encountered and lessons learned from the perspective of both the audit team and the permit holders.