Wood River Watershed Study
The purpose of this Study was to develop the 1% Annual Exceedance Probability (AEP) frequency flow data for the communities of Kearney, Gibbon, Shelton, Wood River, Alda and Grand Island.
HEC-HMS was used to estimate hydrographs for eight flow locations in the area of interest. A HEC-RAS (2D) model was used to route flows through areas of low relief terrain that featured complex flow patterns. Results and modeling will be shared with State and local partners to support ongoing flood risk reduction efforts.
Download the Wood River Watershed Study report.
Lower Platte River Flow Frequency Update
This report is an update to the Lower Platte Flood Frequency Update completed by USACE in 2018. That study utilized data from 1942-2016, which was the most recent data available from the United States Geological Survey (USGS), to compute a mixed population flood flow frequency based on frequency analysis for the rainfall and snowmelt seasons. Since completion of that study, three more years of annual peak flow data have been observed including a flood of record in 2019. This update utilizes the same methodology and techniques as the 2018 study but includes longer periods of record.
Download the Lower Platte Flood Frequency Update report.
2019 – 2022 Flood Workshops
The Nebraska Silver Jackets held three workshops from July 2019 – October 2019.
The July 10, 2019 flood workshop was held in conjunction with the Nebraska Floodplain and Stormwater Managers Association conference in Nebraska City. With over 65 registrants, the conference provided a forum to update participants on changing legislation (Disaster Recovery Reform Act) and changing programs (FEMA Building Resilient Infrastructure and Communities – BRIC) as well as provide lessons learned from the recent March 2019 flood. A summary of the flood event is available as a story map on Nebraska Department of Natural Resources website. Download the July 2019 workshop presentations.
The October 28, 2019 flood workshop was held at the Central Platte Natural Resources District office. After the 2019 flooding, USGS was issued a mission assignment to collect high water marks (HWM) to document the flood; a monumental task given the geographic extent of the impacted area. A task that was greatly assisted by the state and local communities that set high water marks immediately after the flood. The USGS was on-site to give a 1/2 day workshop on how to properly set HWM to additional state and local staff. Download the October 2019 presentation.
The October 27, 2020 flood workshop purpose was to update the public on ongoing activities and resources available through several federal and state partners. USACE provided an update on the Corps Water Management System (CWMS) and ongoing modeling efforts within the USACE Omaha District. USACE also provided information on the newly released Engineering Circular 1110-2-6075 as it pertains to flood inundation mapping and availability to the public. NeDNR provided an update on ongoing floodplain mapping efforts in the State. NEMA provided an update on the draft State Hazard Mitigation Plan. Finally, FEMA provided an update on the BRIC program and the current grant deadlines. Download the October 2020 workshop presentations.
Nebraska's NFIP Loss Properties are Definitively Identified and Mapped
According to FEMA, the number of repetitive flood losses are increasing throughout the country and putting a stress on the National Flood Insurance Program. To address this problem, the Nebraska Silver Jackets Team asked that the USACE assist in reviewing each of the repetitive loss structures in the state and provide a Repetitive Loss Area Analyses so that the statewide hazard mitigation plan can be updated and improved.