LWI Region 3 Modeling Overview

Application to Atlas 14 Rainfall { The variable ARF shapefile was used to adjust Atlas-14 gridded hyetographs for each subbasin location (Figure 4-8). { Adjusted precipitation values were imported into DSS and integrated with RAS-2D ROM models for pluvial and fluvial domains. { For example, a hyetograph comparison showed: o With ARF : 13.01 in total rainfall; 12-hour peak intensity of 1.15 inches/hour. o Without ARF : 11.14 in total rainfall; 12-hour peak intensity of 1.34 inches/hour. Model Calibration and Flexibility { ARF values within shapefiles can be fine-tuned to better match frequency-based rainfall-runoff relationships as observed in gage analyses. { This adaptive approach enhances model accuracy for event simulation and frequency-based design storms.

Figure 4-8: Comparison of Atlas-14 Everywhere vs. Atlas-14 with ARF applied at indicated location, with accumulate rainfall of 13.01 and 11.14 respectively.

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Precipitation and Frequency Analysis and Consequence Modeling