Public input is a key part of the MAAPnext and FEMA review process. Community engagement ensures that the final maps reflect the most accurate, up-to-date information available for Harris County.

If residents, local governments, or technical experts provide data or documentation showing that a mapped area’s flood risk is inaccurate, FEMA may revise the maps before they become final.

Examples of information that can influence changes include:

• New elevation or survey data 
• Drainage or infrastructure improvements completed after the initial study 
• Verified local flood history or high-water marks 
• Technical corrections identified during review

Actionable comments include data, documentation, or information that could affect how the maps are finalized. General feedback or opinions are welcome but are not considered formal comments under FEMA’s review process.

Learn more about the FEMA review and appeal process

The public review and appeal period lasts 90 days, beginning after FEMA releases the Preliminary Flood Insurance Rate Maps for Harris County. During this time, residents, community groups, and local governments can review the maps, attend virtual public open houses, and submit comments or appeals.

Note: Actionable comments include data, documentation, or information that could affect how the maps are finalized. General feedback or opinions are welcome but are not considered formal comments under FEMA’s review process.

Notices about the start and end of the 90-day period will be posted on this MAAPnext website, shared through social media, and distributed to local jurisdictions across Harris County.

We are currently in the draft stage of the MAAPnext mapping process. Draft maps are shared for informational and educational purposes only and are not open for formal comments or appeals yet.

Once FEMA releases the Preliminary Flood Insurance Rate Maps (FIRMs), Harris County residents will be able to review and submit feedback through this MAAPnext website. Comments collected at that stage will be shared with FEMA for awareness, while formal appeals must be submitted directly to FEMA during the official 90-day appeal period.

Learn about FEMA’s Comment and Appeal Process

Flood maps are released in stages as they move through review and approval:

Draft Maps: These are early versions shared with local officials and Floodplain Administrators for internal review. They help identify technical issues or mapping discrepancies. 

Preliminary Maps: Once FEMA reviews and approves the data, Preliminary Flood Insurance Rate Maps (FIRMs) are released for public review. This is when residents can view their property’s new flood risk and submit comments or appeals during the official 90-day review period.

Note: Actionable comments include data, documentation, or information that could affect how the maps are finalized. General feedback or opinions are welcome but are not considered formal comments under FEMA’s review process.

Final (Effective) Maps: After the public comment and appeal period closes and FEMA incorporates any approved changes, the maps become effective. The effective maps are the official regulatory versions used for flood insurance, permitting, and development decisions.

Understanding which stage the maps are in helps clarify what the data can and cannot be used for. For example, draft and preliminary maps are for education and feedback, while only effective maps determine flood insurance and permitting requirements.

There are different ways flood maps can change, depending on where the maps are in FEMA’s review process.

While maps are still draft or preliminary, residents, communities, and technical partners may have an opportunity to submit comments or appeals during FEMA’s public review process. Appeals generally need to be supported by technical or scientific information showing that the flood hazard information should be revised.

After maps become effective, map changes are generally managed through FEMA’s Letter of Map Change process. A Letter of Map Revision, or LOMR, is an official FEMA revision to an effective Flood Insurance Rate Map. A LOMR may be appropriate when new technical information shows that mapped flood elevations, floodplain boundaries, or floodway boundaries should be changed. This could include updated hydrologic or hydraulic modeling, new survey or topographic information, a completed drainage or flood risk reduction project, or another physical change that affects how floodwater moves through an area.

A LOMR is not typically triggered by general concern, past flooding experience alone, or a request to remove an individual property from a floodplain without supporting technical data. For property-specific questions, residents should contact their local floodplain administrator, insurance provider, lender, or FEMA’s Mapping and Insurance eXchange.