Floodplain Remapping Project

Floodplain Remapping Project

VIEW MAPS & PROVIDE FEEDBACK

OFFICIAL FLOODPLAIN MAP

The interactive webmap (use the button above) shows detailed flood risk zones and related FEMA map amendments or revisions 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 map was updated on Aug. 1, 2018 to reflect changes to the Floodplain Overlay District based on Colorado Hazard Mapping Program (CHAMP) Phase II DRAFT floodplain mapping adopted by the BOCC through Land Use Docket Z-17-0002:

  • Stream Reaches Effective Aug. 1, 2018
    • North St. Vrain (Longmont Dam Road)
    • Geer Canyon
    • James Creek
    • Left Hand Creek
    • Lower Fourmile Canyon Creek
    • Gold Run
    • Little Thompson River
    • St. Vrain Creek Floodway
  • Stream Reaches Effective Oct. 1, 2018
    • CHAMP Phase II DRAFT floodway mapping for lower Boulder Creek (Kenosha Road/115th Street to East County Line Road)

NEW INFORMATION

Floodplain Remapping Project Reach map

Phase I Waterways (2017)

  • Cabin Creek
  • North-South-Middle St. Vrain Creek(s)
  • St. Vrain Creek
  • Boulder Creek
  • North Boulder Creek
  • Middle Boulder Creek
  • South Boulder Creek
  • Dry Creek #2
  • Two Mile Canyon Creek
  • Coal Creek
  • Rock Creek
  • New Dry Creek Ditch
  • Upper Fourmile Canyon Creek

Phase II Waterways (2018)

  • North St. Vrain (Longmont Dam Road)
  • Geer Canyon
  • James Creek
  • Left Hand Creek
  • Lower Fourmile Canyon Creek
  • Gold Run
  • Little Thompson River
  • Lower Boulder Creek Floodway
  • St. Vrain Creek Floodway

ABOUT THE MAPS

Map data from Phase I of the CHAMP and related flood studies was adopted by the BOCC through Docket Z-17-0001 and became effective on June 1, 2017. Phase II of CHAMP was adopted by the BOCC through Docket Z-17-0002 and became effective on Aug. 1, 2018 (excluding the lower Boulder Creek floodway from Kenosha Road/115th Street to East County Line Road, which became effective date on Oct. 1. 2018). Map layers in the Phase II were updated as of Aug. 1, 2018 and Oct. 1, 2018, respectively, to reflect these regulatory changes.

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

Contact Us

Floodplain Administrator Contact

Floodplain Administrator

303-441-3900
Email

Floodplain Remapping Program Contact

720-564-2866
Email

Location

2525 13th Street
Boulder, CO 80304

Map & Directions

Hours: 8 a.m. - 4:30 p.m. M-F

Mailing Address

P.O. Box 471
Boulder, CO 80306