Lincoln Flood Map Updates
A FEMA-funded effort to map flood risk more accurately
The City of Lincoln works to keep the community safe from flooding through a variety of flood management projects. The Lincoln Watershed Management division, in partnership with the Federal Emergency Management Agency (FEMA) is working to update flood maps for Lincoln and portions of Lancaster County. This years-long effort will offer up-to-date data that will strengthen the community's understanding and awareness of flood risk.
The City of Lincoln is a cooperating technical partner (CTP) to the Federal Emergency Management Agency (FEMA) to update the flood maps in Lincoln/Lancaster County.
- FEMA is responsible for mapping the country’s flood risks and is providing 100% of the funding for this project.
- The effective flood maps for Lincoln are from the early 2010s; however, some of the underlying data is much older than that, such as rainfall data dating back to 1961.
- The flood maps will be updated using more current topography and rainfall data and improved modeling methodology to map flood risks more accurately.
- Updated flood maps will offer the City additional data to help put flood management projects in place to continue to protect the community from potential flooding.
FEMA flood maps are created through a process called Risk Mapping, Assessment, and Planning, or Risk MAP. This process has four steps:
- 1 In the Discovery step, the project team will collect data and information to develop a thorough understanding of the watershed’s flood risk challenges and concerns.
- 2 In the Analysis & Mapping step, significant engineering analysis results in the development of initial draft maps, called work maps. These maps will undergo technical review. This step may include identification of flood mitigation strategies.
- 3 In the Preliminary Flood Map Release step, work maps are progressed to preliminary flood maps. In this step, community members will be invited to review and comment on the updated maps, which are still considered draft.
- 4 In the Map Adoption step, FEMA finalizes and adopts the flood map, which was developed in accordance with FEMA’s guidance and standards.
The City will complete the data collection and analysis to develop preliminary flood maps (steps 1, 2, and 3), while FEMA provides oversight and performs due diligence prior to map adoption (step 4).
The project includes 13 watersheds within Lincoln and portions of Lancaster County, and each watershed will progress through FEMA’s four-step Risk MAP process. The 13 watersheds are in four phased groups as follows:
- Phase 1: Cardwell Branch, Beal Slough
- Phase 2: Stevens Creek, Southeast Upper Salt Creek, Upper Wagon Train
- Phase 3: Little Salt Creek, Oak Creek, Middle Creek, Haines Branch
- Phase 4: North Salt Creek, Deadmans Run, Antelope Creek, South Salt Creek
Each phase will pause at the end of step three. At which point the City will conduct city-wide floodway modeling and produce a comprehensive floodway map, among other Risk MAP products.
The City of Lincoln will submit its technical work to FEMA for final review and adoption.
Project work began August 1, 2023.
|Risk MAP Step
|1 – Discovery
- Topographic surveying to begin September 2023
- Work anticipated to start in January 2024
- Work anticipated to start in April 2025
- Work anticipated to start in April 2026
|City-wide Flood Maps and Risk MAP products
- Work anticipated to start in October 2027
* Dates after 2023 are approximate and dependent on FEMA funding distribution.
There will be a variety of opportunities for public input throughout the Risk MAP process, notably in Risk MAP steps one and three.
The first opportunity for input will be specific to Phase 1. More information will be provided as soon as it is available.