Floodplain maps are updated in periodic intervals by an act of Congress in order to reflect changing conditions and priorities.
Creating digital floodplain maps is complex and challenging. The process overlays floodplain maps onto an ortho-photo base map. Each layer of information must be registered to the base map and go through a quality control process to ensure that the data have been accurately compiled before it is published.
The State undertook a project to collect elevation using LiDAR (Light Detection and Ranging). The two-foot elevation contour lines are more accurate and are now used for floodplain mapping.
The following are the active and recent flood map updates relevant to the state of Maine.
FEMA Risk Map
Flood risk can change over time because of new development, weather patterns, and other factors. FEMA works with federal, state, tribal, and local partners to identify flood risk and help reduce that risk through the Risk Mapping, Assessment and Planning (Risk MAP) program.
Risk MAP provides flood maps and information, tools to manage flood risk, and planning and outreach support to communities to help them take action to reduce or mitigate flood risk. Each Risk MAP project is tailored to the needs of each community and may involve different products and services.
- Map Update Status (PDF), last updated Sept. 16, 2026
- Map Updates Timeline (XLSX, CSV), last updated Sept. 16, 2026
- Moving to Digital Flood Hazard Information (PDF)
- Sample field survey Surveyor Letter (PDF)
FEMA currently has several remapping projects underway in Maine. The accuracy of flood maps is important for determining flood insurance rates, local and state permitting, and lending institutions rely on them when deciding to grant loans for structures located in the floodplain. The goal is to use local knowledge to help create a more accurate product.