LWI Region 3 Modeling Overview

2. Model development and calibration: The two major components of the second phase included the following: { Channel and hydraulic structure survey: Survey data was collected for all four watersheds, including a channel cross section survey and bridge, culvert, levee outlets, diversions, dams and weirs. Pump station operation information was also obtained, and field trips were conducted to better understand the Region’s drainage patterns. { Model development and calibration: Watershed wide models were developed and calibrated to a selection of the following rainfall events, as appropriate for each watershed: • September 2008 (Hurricane Gustav): short event • May 2009: short event • September-November 2009: multiple days and backwater event • March 2016: historic event • February-May 2018: multiple days and backwater event • May 2019: short, backwater event

• September 2019: short, low flow event • September-October 2020: multiple days • January 2013: short event

3. Design storm events and consequence assessment:

The calibrated models developed in the second phase for each watershed were used to evaluate 35 design storm events of multiple frequencies and durations. Consequence Assessment was performed using Go Consequence for each of the 35 events.

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LWI Model Development Phases