FEMA flood map notices

Flood map changes in Boulder County, Colorado

FEMA has published 34 flood hazard notices covering Boulder County, Colorado since November 2023. The most recent, map revision flood hazard determinations, was published Sep 10, 2026.

Notices for Boulder County

Sep 10, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 22 other counties
Aug 21, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 19 other counties
Aug 21, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 24 other counties
Jul 9, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 13 other counties
Jul 9, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 29 other counties
Jun 11, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 29 other counties
Jun 11, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 22 other counties
May 18, 2026Map revisionChanges in Flood Hazard DeterminationsAlso covers 29 other counties
Dec 18, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 28 other counties
Dec 8, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 25 other counties
Oct 2, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 18 other counties
Oct 2, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 30 other counties
Aug 20, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 32 other counties
Jul 9, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 9 other counties
Jun 12, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 29 other counties
Jun 11, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 31 other counties
May 12, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 27 other counties
Mar 26, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 27 other counties
Feb 24, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 9 other counties
Feb 24, 2025Map revisionChanges in Flood Hazard DeterminationsAlso covers 27 other counties
Dec 18, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 19 other counties
Oct 24, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 23 other counties
Oct 22, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 24 other counties
Aug 12, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 20 other counties
Aug 1, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 19 other counties
Jun 28, 2024FinalFinal Flood Hazard DeterminationsAlso covers 3 other counties
May 16, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 24 other counties
Apr 29, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 27 other counties
Apr 18, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 24 other counties
Mar 14, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 22 other counties
Feb 15, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 19 other counties
Jan 22, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 27 other counties
Jan 11, 2024Map revisionChanges in Flood Hazard DeterminationsAlso covers 25 other counties
Nov 3, 2023Map revisionChanges in Flood Hazard DeterminationsAlso covers 22 other counties

Also covered by these notices

FEMA often studies whole watersheds, so one notice can span several counties.

What these notices mean

Proposed: FEMA has new draft flood maps. This starts a 90-day window when owners can appeal with technical data. It's the best time to act.
Final: Appeals are resolved. The new maps usually take effect about six months later, when lenders start applying the new zones.
Map revision: A Letter of Map Revision changes one stretch of the map, often after a levee, channel project or new survey.

Notices are organized by county and community, so a notice for your county doesn't mean your property is changing zones. What flood zones mean