Although many approaches have been proposed for flood risk assessment in urban areas, an equivalent methodology for remote mine sites with poor hydrological data records is still needed. This paper provides a fuzzy methodology based on calculating the hydrological return period discharge and the resistance-load theory for embankment failure risk assessment of an existing drainage storage system (lake) at the Golgohar mine site. The uncertainty of the two uncertain components, load and resistance, were endowed with triangular fuzzy numbers (TFNs) describing possible values the two components may have. First, based on a comparison of two consecutive Sentinel-2A images and the model water volume, a new manual storm water management model (SWMM) calibration technique was introduced. Then, three well-known synthetic rainfall hyetograph generation methods based on a single point of the rainfall curve were input into the calibrated SWMM model. Second, the BRCH-J model was used to calculate the maximum water level in the lake if an embankment breach occurs in two scenarios, with an unprotected and a fully riprap-protected downstream face. Afterward, the SWMM and BRCH-J outputs were used to define the TFN parameters representing the load (surface flow) and resistance (lake capacity). Finally, on the basis that both TFNs must match, a fuzzy risk product with alpha-cut principles was defined, as was the difference between the TFNs representing the load and resistance. The result indicates that the available stormwater storage volume exceeded the expected capacity; the risk of embankment failure was 0.15%, which was less than the design risk (1%, based on the hydrological return period concept).

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