Accelerated slab breakup was noted on many retrofit-edge-drain-only and rehabilitated concrete pavements in California. Concern about the earlier-than-anticipated need for further rehabilitation led to an evaluation of 26 projects that incorporated retrofit edge drains. Results of this study show that before retrofit edge drain installation, the amount of slab breakup and environmental factors significantly affect subsequent pavement performance. More important, it is also suggested that environmental factors strongly influence the undrained performance of concrete pavement. Therefore, the future use of current and alternative concrete pavement designs should address environmental factors that can contribute to poor pavement performance in California.