Challenge
A significant number of maps for New Mexico counties were not modernized during Flood Map Modernization. Only hard copy Flood Insurance Rate Maps (FIRMs) were available, limiting the ability to view the Special Flood Hazard Area (SFHA) data.
Solution
The Earth Data Analysis Center (EDAC) at the University of New Mexico and the New Mexico Department of Homeland Security and Emergency Management (DHSEM), both Cooperating Technical Partners, obtained funding from the Federal Emergency Management Agency (FEMA) to convert hardcopy Flood Insurance Rate Maps (FIRMs) into a digital format and make them available via a publicly accessible website. EDAC, which manages the New Mexico Resource Geographic Information System (RGIS) Program and Clearinghouse, has been in the spatial data business for over 50 years. The New Mexico RGIS is one of the largest state-based programs for digital geospatial data in the nation. DHSEM manages the state’s floodplain management program and leads the state’s response to emergencies and disasters.
Outcome/Results
NMFlood.org is a public website developed and hosted by EDAC in collaboration with DHSEM to provide geospatial support to New
Mexico communities that are at risk of flooding. After obtaining scanned hard copies of FIRMs from FEMA, EDAC georeferenced the scans and generated vector geospatial datasets of the Special Flood Hazard Areas (SFHAs) depicted on these FIRMs. EDAC then developed a web application that allowed these data to be viewed with a variety of geospatial base maps for each of the counties. The web application enables users to view both the georeferenced scanned FIRMs and the geospatial lines representing the extent of inundation related to the SFHA.
Benefit
Benefits associated with developing vector datasets associated with the SFHAs and making them available on a publicly accessible website:
- Allows comparison of currently available flood hazard mapping against locally recognizable base maps
- Provides counties currently relying on hardcopy FIRMs with an easy to use a digital tool to manage development in their county
- Provides the state with a complete geospatial SFHA dataset to help identify at-risk populations and structures
- Provides for a full flood risk profile for all mapped SFHAs in New Mexico
- Provides the base data for the New Mexico Hazard Mitigation Plan
- Provides New Mexico with the data needed to assess current flood risks
- Identifies potentially dangerous low-water crossings
- Offers data points for prioritization of flood hazard mapping updates
- Identifies mitigation activity opportunities for long-term risk reduction
Lessons Learned
Risk Mapping, Assessment, and Planning Program (Risk MAP) Phases
This project involved the following Risk MAP phases:
- Discovery
- Data Development and Sharing
- Risk Awareness and Mitigation Outreach
Risk MAP Goals Advanced
The Risk MAP goals that were advanced through this project included:
- Advancing Action
- Identify Action
- Increasing Awareness
Georeferencing scanned FIRMs causes some warping of the lines associated with SFHAs. Including both the scanned FIRMs and the vector data enables the user to see the source mapping used to generate the vector SFHA data. When visiting the website, the introductory page includes a text box that states, “The maps and data presented are informational only and are not suitable for legal or engineering purposes.” The user must acknowledge their understanding of this limitation before proceeding.
Resources
A set of interactive maps is available at NMFlood.org. The site includes status maps for FEMA flood mapping, new and/or updated mapping being developed under FEMA’s Risk MAP program, and LiDAR topographic mapping initiatives. This is in addition to FEMA’s digital FIRM data and flood maps georeferenced by EDAC for the 10 counties in which FEMA has only provided hard copy FIRMs.
Contact Information
Shawn Penman, PhD, CFM, GISP
New Mexico CTP Coordinator
spenman@edac.unm.edu