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Floodplain Remapping Project

Floodplain Remapping Project



The interactive web map (use the button above) shows detailed flood risk zones and related FEMA map amendments that are currently regulated throughout unincorporated Boulder County as Floodplain Overlay Zoning District. This map will update as new FEMA maps become effective throughout Boulder County and as the Boulder County Board of County Commissioners (BOCC) adopts best available information.

The Boulder County Regulatory Flood Risk Zones were updated on Jan. 10, 2020 to reflect changes to the Floodplain Overlay District based on FEMA’s Preliminary Flood Insurance Rate Maps (FIRMs) for stream reaches studied by the Colorado Hazard Mapping Program (CHAMP). The Preliminary FIRMs were adopted by the BOCC via Docket Z-19-0001.


Visit the interactive web map (use button above) to view FEMA’s Preliminary Flood Insurance Rate Maps (FIRMs) for stream reaches studied by CHAMP. We expect the CHAMP Preliminary FIRMs will become effective FIRMs in 2021, pending any appeals received by FEMA. At that time, the updated CHAMP mapping will be used for flood insurance rating.



Floodplain remapping stream reaches for 2019-2020 effort

Following the 2013 Flood, the Colorado Water Conservation Board (CWCB) initiated a program to re-map the predicted 1% annual chance flood zone (100-year floodplain) of the most affected waterways (shown in the image above). The program was called the “Colorado Hazard Mapping Program,” or CHAMP. Draft map data and related flood studies for the CHAMP– studied reaches were adopted by the Board of County Commissioners (BOCC) through Docket Z-17-0001 and Docket Z-17-0002. In September 2019, FEMA released Preliminary Flood Insurance Rate Maps (FIRMs) for the same CHAMP reaches, refining the draft maps. The Preliminary FIRMs were adopted by the BOCC, replacing the draft map data via Docket Z-19-0001 to allow the county to base floodplain regulations on the best available data. In 2022, upon final FEMA approval and adoption, the floodplain mapping will become for flood insurance purposes.

Please contact the Floodplain Management Team (info below) with questions or to learn more about the floodplain mapping changes.

Contact Us

Community Planning & Permitting - Floodplain Administration



2045 13th Street
Boulder, CO 80302

Map & Directions

Hours are Monday, Wednesday, and Thursday from 8 a.m. to 3 p.m., and on Tuesday from 10 a.m. to 3 p.m.

Mailing Address

Community Planning & Permitting
Floodplain Administration
P.O. Box 471
Boulder, CO 80306