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The Mw 7.8 Earthquake with an epicenter in Muisne, Ecuador, on April 16, 2016, caused an extensive damage to critical infrastructure due to liquefaction-induced settlement and lateral spreading of alluvial soils across the Ecuadorian coastal region. Reconnaissance observations were performed after the event by the Geotechnical Extreme Events Reconnaissance (GEER) Team. This paper presents a case study to compare the estimated liquefaction susceptibility, liquefaction settlement, and ejecta, based on traditional simplified in situ-based liquefaction approaches, to the observed liquefaction documented by the GEER after the event. The study area focuses on the Puerto of Manta, a critical infrastructure that suffered liquefaction-induced settlement, liquefaction ejecta, and lateral spreading of the slope sides near to pile-supported wharves. Several in situ testing and laboratory tests, including Standard Penetration Tests (SPT), Cone Penetration Test with pore pressure measurement (CPTu), and downhole tests for shear wave velocity (Vs) measurements, were performed before and after the event occurred in the study area. The seismic demand for liquefaction evaluation was obtained from two approaches: (1) By using the maximum horizontal acceleration in each component (NS, EW) obtained from the National Network of Accelerographs (RENAC) of the AMNT Station located in the City of Manta approximately 1.1 km from the study area; and (2) By performing a non-linear site response analysis (SRA) of the study area based on a deconvoluted ground motion, to consider the effect of subsurface variability between the station location and the study area. Results indicated that although the seismic demand at ground level (i.e., peak ground acceleration, PGA) by performing the deconvolution and SRA is approximately 50% less than the seismic demand recorded from the station, the estimated liquefaction settlement, Liquefaction Potential Index (LPI), and ejecta does not indicate a significant variation with the reduction in seismic demand. The authors concluded that, although the subsurface conditions varied between the station location and the study area, the effect of the PGA on the estimation of liquefaction settlement, liquefaction potential index, and ejecta, based on simplified methods, is not significant to justify performing a deconvolution and SRA. The estimated liquefaction settlements resulted in being within the range of observed settlements by GEER with both seismic demands. A simplified liquefaction evaluation based on the PGA obtained from nearby stations is sufficient for estimation of liquefaction settlement in areas where rock is relatively shallow, and its magnitude, in this case study, was validated with the truth observed settlements after the seismic event.