This research proposes an ex post methodology for analyzing the influence of Hazard Mitigation Plans in the level of resilience in localities affected by an extreme event. For verifying its applicability, the case of heavy rainfalls of the 2017 coastal El Niño event in Peru is analyzed. The methodology consists of two analysis levels. The first one correlates the quality of existing plans with damages and recovery rapidity. The second analysis level focuses on one sample of the localities selected for performing a deeper qualitative-territorial analysis. The methodology applicability was verified, and we determined that the reduction of direct damages after an event is correlated to the existence of actions such as land use regulation and the structural reinforcement. Moreover, the identification of those responsible for these processes, the verification of possible financing funds and the estimation of intervention costs positively influence on the reconstruction rapidity.