We’re excited to announce that HEI’s Connor Kelley and Bob Gregalunas will be presenting two insightful sessions at the 2025 Nebraska Floodplain and Stormwater Managers Association (NeFSMA) Conference, held July 17 in Lincoln, NE. We’re proud to contribute to the conversation on flood resilience and hydrologic innovation. If you’re attending NeFSMA 2025, don’t miss these sessions!
How Did it Age? Validating a Decade-Old Hydrologic Study
This session revisits a 10-year-old hydrologic update for the Papillion Creek watershed—one that significantly lowered discharge estimates. The original study was a dramatic departure from previous analyses and lowered discharge magnitudes significantly within the basin. Using forensic hydrometeorological analysis of the May 2024 flood in Douglas County, Connor and Bob will compare the model’s simulation against observed data at specific USGS gage locations. We’ll dive deep into a history of soil loss and rainfall-runoff methods to understand why this departure is expected and justified as we shift toward highly detailed rainfall data.
Lake Wanahoo Flood Forensics
In this talk, Connor dives into the May 2024 flood event that exceeded the 1% annual chance threshold on Sand Creek and Lake Wanahoo. By integrating drone imagery, lake stage data, and radar-corrected precipitation with advanced 1D, 2D, and 3D hydraulic modeling, including 3D computational fluid dynamics analysis of the dam’s outlet, this session offers a compelling look at how data-driven insights inform resilient infrastructure design.