The design tailwater was updated to utilize gage information from the USGS gage 02296750, Peace River at Arcadia, FL to replicate the recorded elevations of the river during the monitoring period. For this study, the time stage curve spans from September 28th, 2022 at 8:30am to October 3rd, 2022 at 8:30am, a total duration of 120 hours. The start time of the simulation was set 12 hours before the calculated time of the eye of the hurricane being over Arcadia, FL which was estimated to be September 28th at 8:30pm. The simulation ended 49.5 hours after the rivers peak was recorded on
Figure 10 - USGS Peace River Elevations for Monitoring Period
NEXRAD rainfall data was obtained from South West Florida Water Management District (SWFWMD) for the monitoring period to set basin specific rainfall throughout the model. Subdivided areas, referred to as tiles, have individual monitoring gages which provide more detailed rainfall estimates across large project areas, as opposed to using a global rainfall estimate in the modeling. Seven NEXRAD tiles spanned the model area, with cumulative rainfalls varying from 17.50 inches to 18.61 inches. It should be noted rainfall was only recorded on September 28th, 2022. See Figure 11 for the NEXRAD tile layout with cumulative rainfall listed. Figure 12 compares the unit hydrograph for each tile. For comparison purposes, this figure also depicts the global rainfall (16.5 inches) Florida Modified (FLMOD) unit hydrograph to show a global modeling approach would have underestimated the storms impacts.
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