Understanding Flood Maps
How do I find out if my property is in a flood zone?
You can check your property's flood zone designation on FEMA's Flood Map Service Center at msc.fema.gov. Enter your address to view the effective Flood Insurance Rate Map (FIRM) for your location. The map will show whether your property is in a Special Flood Hazard Area (zones starting with A or V) or outside the mapped floodplain (zones X or C).
What is a Base Flood Elevation (BFE)?
The Base Flood Elevation is the computed elevation to which floodwater is anticipated to rise during the 1% annual chance flood (formerly called the "100-year flood"). Buildings in Special Flood Hazard Areas must typically be elevated to or above the BFE. The BFE is also used to determine flood insurance premiums.
What's the difference between Zone A and Zone AE?
Both are Special Flood Hazard Areas with a 1% annual chance of flooding. Zone AE has detailed study with established Base Flood Elevations shown on the FIRM. Zone A is an approximate study area without detailed elevation data - the BFE must be determined through additional analysis if needed for permitting or insurance purposes.
My property was recently mapped into a flood zone. What are my options?
If you believe the mapping is incorrect, you may be eligible for a Letter of Map Amendment (LOMA) if your structure's lowest floor is above the Base Flood Elevation. Alternatively, you could pursue a Letter of Map Revision (LOMR) if there are errors in the underlying study or if physical changes to the floodplain have occurred. We can evaluate your situation and recommend the appropriate approach.
Letters of Map Change (LOMC)
What's the difference between a LOMA and a LOMR?
A LOMA (Letter of Map Amendment) removes a structure from the Special Flood Hazard Area based on elevation data, without changing the flood map itself. A LOMR (Letter of Map Revision) revises the actual flood map based on new studies, physical changes, or corrected data, and can affect larger areas beyond a single property.
How long does the LOMC process take?
FEMA's target review time is 60-90 days from receipt of a complete application, though complex cases may take longer. The total timeline also depends on how long it takes to gather required data, prepare the technical documentation, and respond to any FEMA comments. We typically advise planning for 3-6 months from project initiation to final determination.
How much does a LOMA or LOMR cost?
FEMA does not charge a fee for LOMC applications. However, professional fees for engineering services vary based on project complexity, data requirements, and analysis needed. Contact us for a project-specific quote after we review your situation.
Can I apply for a LOMC myself, or do I need an engineer?
While property owners can submit their own LOMA applications for simple cases, most applications require professional engineering support. Engineers licensed in your state must certify elevation data and hydraulic analyses. The technical complexity and FEMA's strict requirements make professional assistance advisable for most applications.
Working with BaseFlood Engineering
What geographic areas do you serve?
We provide services nationwide for FEMA-related flood risk projects. While we're not physically present in every location, modern technology allows us to work effectively on projects across the country. For projects requiring professional engineering seal, we work with licensed engineers in your state as needed.
How do I get started with a project?
Contact us through our contact form or email with information about your project location, the type of service you need, and your timeline. We'll schedule a consultation to discuss your specific situation, evaluate feasibility, and provide a scope and fee proposal.
Do you provide flood insurance?
No, we are an engineering consulting firm and do not sell insurance. However, we provide the technical analysis and documentation that supports flood insurance rate reductions, LOMC applications, and compliance with insurance requirements. We recommend working with a qualified insurance agent for insurance-specific questions.
What information do I need to provide to get started?
At minimum, we need the property address or coordinates, a description of what you're trying to accomplish, and any relevant existing documentation (surveys, previous studies, permits, etc.). The specific data requirements depend on the type of service - we'll provide a detailed checklist during our initial consultation.
Technical Questions
What is a "no-rise" certification?
A no-rise certification documents that proposed development within a regulatory floodway will not increase the Base Flood Elevation by more than a specified amount (typically 0.00 feet). This certification, prepared by a licensed engineer using hydraulic modeling, is required for most development in floodways.
What software do you use for hydraulic modeling?
We primarily use HEC-RAS for hydraulic modeling and HEC-HMS for hydrologic analysis, as these are the industry-standard tools accepted by FEMA. We also work with various GIS platforms, survey processing software, and specialized tools depending on project requirements.
Can you help with coastal flooding or storm surge?
Yes, we have experience with coastal flood hazard analysis, though our primary focus is on riverine and pluvial (rainfall-driven) flooding. For complex coastal projects involving wave modeling or surge analysis, we can coordinate with specialized coastal engineers as needed.
Still Have Questions?
We're here to help. Contact us with your specific questions about flood risk, FEMA requirements, or our services.
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