Infrastructure mega-projects are highly important for economic and societal growth, but they are also extremely susceptible to a high degree of risks leading to massive delays. These delays affect not only the project schedule but also the cost and the quality. The delay events are present throughout the project life cycle but, according to the researcher’s observation, most of the delays were found to occur in the design-construction interface. In general, the problem of delay has been studied a lot by previous researchers; however, being one of the critical phases, delays in the design-construction interface have still not been investigated. Therefore, this research conducts a detailed study for developing mitigation measures for delays within the design-construction interface in the infrastructure mega-project. To achieve the above goal, the research investigates critical events in an infrastructure megaproject to develop measures with the help of the critical incident technique (CIT). CIT was used for the research because it helped in evaluating the success or failure of the adopted and recommended measures. Based on the evaluation the research proposed a preventive and corrective measure framework to minimize the delay's effect on the project schedule.