LWI Region 3 Modeling Overview

Model Calibration and Validation { Calibration events: Dec 2014, Mar 2016, Feb 2018, May 2019, Aug 2019, Sep 2020, Oct 2020, and Aug 2022 { Validation events: Nov 2015, Feb 2020, and Jun 2021 { Parameters calibrated: • Subbasin time of concentration • Storage coefficient • Antecedent moisture conditions • Routing parameters (e.g., Manning’s n) { Comparison of calibrated vs. uncalibrated outputs shown in Figure 3-17; full details below: LEARN MORE: B_HMS_APPENDIX_3 + Recurrence Interval Analysis { 35 storm events simulated using Atlas 14 precipitation data Atlas 14 Precipitation { Model outputs validated against Bulletin 17C Expected Moments Algorithm peak flow estimates at the Eudora gage (Figure 3-18) { Example outlet hydrographs shown in Figure 3-18.

Figure 3-17: Comparison of model results for May 2019 calibration event at watershed outlet before and after calibration.

Figure 3-18: 100yr_24hr Model Outlet Hydrograph versus EMA Peak Flow estimate and confidence limits.

Figure 3-19: Comparison of results at HMS model outlet of all 24-hour duration events, varying recurrence interval.

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Hydrologic and Hydraulic Modeling Methodology