Floodplain Mapping – FEMA Appeals

The Boulder County Community Planning & Permitting office at 2045 13th St., Boulder is open to the public on Monday, Wednesday, and Thursday from 8 a.m. to 3 p.m., and on Tuesday from 10 a.m. to 3 p.m. Appointments are available on Tuesday but are not required. Schedule an appointment.

Floodplain Remapping Project - Making appeals to FEMA for map amendments

FEMA is no longer accepting appeals

In 2020 and 2021, FEMA ran 90-day appeal periods where anyone could appeal or comment on the Preliminary Flood Insurance Rate Maps (Preliminary FIRMs) that had been released in 2019. Boulder County received and submitted to FEMA ten appeals and four comments over the course of the appeal periods. As a result of the appeals, the Preliminary FIRMs were revised in the eight areas described below. The revised Preliminary FIRMs were released in July 2023 and we expect them to become the effective FIRMs in 2024.

Approved appeals:

  1. Private access bridge at 7871 Lefthand Canyon Drive. This bridge replacement was funded with Community Development Block Grant Disaster Recovery (CDBG-DR) funds and FEMA agreed to incorporate the bridge into the floodplain mapping via the appeal process.
  2. Private access bridge at 618 Apple Valley Road. This bridge replacement was funded with Community Development Block Grant Disaster Recovery (CDBG-DR) funds and FEMA agreed to incorporate the bridge into the floodplain mapping via the appeal process.
  3. Private access bridge at 28328 South Saint Vrain Drive. This bridge replacement was funded with Community Development Block Grant Disaster Recovery (CDBG-DR) funds and FEMA agreed to incorporate the bridge into the floodplain mapping via the appeal process.
  4. Private access bridge at 38148 Boulder Canyon Drive – modified ineffective flow areas based on additional or more accurate information.
  5. 69 Hover Road – changed a small area from Zone AE to Zone AO based on topographic information.
  6. Highway 119 in the City of Longmont – eliminated highway overtopping based on additional topographic information and more detailed hydraulic analysis.
  7. Town of Erie planning area on Kenosha Road – showed additional Floodway encroachment based on more detailed hydraulic analysis.
  8. Lefthand Creek downstream of US 36 and upstream of 49th Street – this appeal was resolved through a third-party Scientific Resolution Panel. Based on the panel’s recommendation, the CHAMP mapping will not become the effective FIRMs in this area of Lefthand Creek only. Instead, this area will be re-studied using a different hydraulic modeling technique. The re-study is expected to take several years.

Archive Appeal Information

FEMA ran a 90-day appeal period from March to June, 2020. Due to the pandemic and the need for most appellants to submit additional information, FEMA ran a second appeal period from February to May 2021.

Before the floodplain mapping from the Colorado Hazard Mapping Program (CHAMP) is incorporated into the effective FEMA Flood Insurance Rate Maps (FIRMs), there will be a 90-day appeal period. During the appeal period, anyone can submit and appeal or comment to the Boulder County Floodplain Administrator. All submissions must be accompanied by the county’s Comment and Appeal Form, to be completed by the applicant. The county will then forward all submissions to FEMA for their review. FEMA will not accept appeals or comments that are not first submitted to the county.

What is an Appeal?

An Appeal is a formal request to have a FIRM amended based on an additional engineering study, which must include data that proves the proposed flood hazard information is scientifically or technically incorrect; contains an indisputable mathematical or measurement error; or, reflects that a changed physical condition has occurred. All Appeals must be certified by a registered professional engineer or licensed land surveyor and must include the required revisions to the FIRM and/or the Flood Insurance Study (FIS) report.

What is a Comment?

A Comment is any submittal that does not meet the requirements outlined for an appeal (above). Comments may include: feedback regarding road names, jurisdictional boundaries and other base map features; concerns regarding proposed flood hazard information; or, any technical submittal that does not meet the full requirements for appeals.

What happens after an appeal is submitted?

FEMA will review the submitted information and prepare an acknowledgement that will state one of the following:

  • The appeal is valid and a change to the Preliminary FIRM and/or FIS is warranted
  • Additional data or information is needed to complete the review. The appellant will have 30-days to provide additional information
  • The information is considered a Comment and will not be incorporated

Should I consider a LOMA instead of an Appeal?

Due to map scale limitations, making flood zone changes at the individual lot or structure level impossible to show on the FIRM. The appeals process typically cannot be used to remove a structure or property from the floodplain. Instead, FEMA’s Letter of Map Amendment (LOMA) process is the avenue to follow for this purpose. Because LOMAs officially change the flood zone designation for a structure or property on an effective FIRM, not a Preliminary FIRM, it is recommended that applicants submit their CHAMP-related LOMA application directly to FEMA through their online Letter of Map Change application portal 30 to 60 days prior to the effective date for the Preliminary FIRMs (likely in 2021). Once approved, an official amendment to an effective map is sent out by letter to the property owner. Please note that LOMAs apply to individual structures or properties and do not change the flood zone boundaries on the FIRM.

Contact Us

Community Planning & Permitting - Floodplain Administration

Email: floodplainadmin@bouldercounty.gov


2045 13th St.
Boulder, CO 80302

Map and Directions


8 a.m. to 3 p.m. Monday, Wednesday, Thursday
10 a.m. to 3 p.m. Tuesday

Mailing Address

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