Is the flood model calibrated to the Eldorado Springs gage data? If not, will FEMA question the studys results?
The hydrology model was calibrated using extensive rainfall data for three storm events (September 1938, May 1969, 1998 thunderstorm). The calibration was then validated through a “blind” analysis of a fourth storm event (1999 thunderstorm). Model calibration was not based directly on the Eldorado Springs gage because this is the only gage record for the South Boulder Creek basin and it is located well above the valley where flooding is critical. However, the calibration analyses using the four storms produced results consistent with flow rates and storm volumes recorded at the Eldorado Springs gage for these events. The hydraulic model was calibrated using historical information and visual records from the 1969 flood. The base model was refitted with topographic conditions representing those that existed in 1969, and the extent of flooding was compared to photographic evidence and recounts from area residents. The overall calibration effort produced successful results that were consis
