Potential FEMA Flood Map Changes


DURATION 5 minute read

Potential FEMA Flood Map Changes

Harris County, as well as other local jurisdictions, are weighing the possibility of updating FEMA flood maps in their area. Below is an overview of the process as well as some ways to stay involved and informed.

FEMA’s Flood Hazard Mapping Program
Informs communities of flood risk
Helps identify Special Flood Hazard Areas (SFHAs), which helps determine insurance rates through the National Flood Insurance Program (NFIP)
Sets community minimums for floodplain and building standards
Reflects current development patterns in the region

FIRM & FIS Development Process

A Risk MAP (Mapping, Assessment, and Planning) is developed using the best technical data to create flood hazard maps that outline flood risk areas. Flood Insurance Rate Maps (FIRMs) include information such as data for river flow, storm tides, hydrologic/hydraulic analyses, and rainfall and topographic surveys. Any additional, valid information received from property owners and communities is taken into consideration.

A watershed is selected by evaluating the risk, availability of elevation data, regional knowledge of issues, and input from local authorities, the community, and other stakeholders. The watershed is reviewed to determine if a FIRM or other flood risk product, like a Flood Insurance Study (FIS) is needed.

As part of the discovery process, FEMA, state, and local representatives collect current and historic flood-related data including: hydrologic & hydraulic models, infrastructure, land use, and any floodplain or base maps that may already exist. This gives insight into whether a flood risk project is necessary and what the scope of the potential project might be.

Data & Mapping
FEMA, along with mapping partners, will prepare data, maps, and any necessary flood risk products once a flood risk project is initiated. This may include the FIRM and the FIS along with non-regulatory flood risk products.

Flood Risk Review Meeting
A Flood Risk Review Meeting may be organized to give officials opportunity to review and give early feedback on draft versions of the FIRM, FIS, and other flood risk products. With the information provided, community officials may communicate with the public about possible changes to their flood risk and begin to identify mitigation measures.

Resilience Meeting
To help communities prepare for the future, a Resilience Meeting is held. This can take place before or after the preliminary FIRM has been released. During this meeting, FEMA, state and local officials will discuss ways to reduce flood risk, determine factors that may be contributing to flooding in the project area, and ways Risk MAP products may support ongoing risk assessment and planning efforts.

Preliminary FIRM
FEMA will release preliminary versions of the FIRM and the FIS to community officials and online through the Flood Map Service Center. Once put into effect, these products will show new or updated flood hazard data which may affect floodplain development requirements or flood insurance rates.

CCO Meeting & Public Open House
A FEMA Consultation Coordination Officer (CCO) will facilitate a meeting to present the preliminary FIRM and FIS information to local officials and then hold an open house for the public to discuss possible changes.

Appeal Period
After the CCO meeting and a public notification process is complete, there will be a 90-day appeal period for communities with new or updated flood hazards. During this time, communities can submit data to revise the FIRM if they believe it is scientifically or technically incorrect. FEMA will review these appeals and make changes as necessary based on the information given.

Effective FIRM and FIS
Once all appeals have been resolved, FEMA will send local officials a Letter of Final Determination six months prior to the FIRM and FIS becoming effective. It is during this time that communities may adopt or amend their floodplain management ordinance to reflect the new maps.

After the FIRM has taken effect, it will be available through FEMA’s Flood Map Service Center.

Take Initiative
Are you in a flood zone?
The National Flood Insurance Program (NFIP) offers flood insurance to homeowners, renters, and business owners if their community participates in the NFIP. Participating communities agree to adopt and enforce ordinances that meet or exceed FEMA requirements to reduce the risk of flooding.
Do you have helpful information?
Assist in the collaboration process by providing any relevant flooding information to your floodplain officials.
Do you have something to say?
Know the process and submit comments, appeals, or letters of map change (LOMCs) at the appropriate time.
Are you working on a project?
Submit any letters of map revision (LOMRs) within 6 months of project completion for projects that change flood hazards in specified areas.

More Information
For more information on Texas’ Risk MAPs check out

To check out the FIRM in your area, go to

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