FEMA Map Revisions
Navigate the FIRM revision process with confidence
Overview
We provide comprehensive support for Letters of Map Change (LOMC), helping property owners and developers obtain official revisions to FEMA Flood Insurance Rate Maps. Our expertise ensures your applications are technically sound, complete, and compliant with FEMA requirements.
Services Include
- LOMA (Letter of Map Amendment): Remove structures from Special Flood Hazard Areas based on elevation data
- LOMR (Letter of Map Revision): Revise flood maps based on new hydrologic/hydraulic studies or physical changes
- LOMR-F (Fill-based revisions): Document fill placement to elevate property above Base Flood Elevation
- Conditional Letters: Obtain pre-construction approval for proposed conditions
- PMR (Physical Map Revision): Update maps to reflect as-built conditions
Our Process
- Initial site evaluation and determination of appropriate LOMC type
- Data collection including surveys, existing studies, and as-built documentation
- Technical analysis and preparation of engineering documentation
- Application assembly with all required forms and supporting materials
- Submittal to FEMA and coordination through review process
- Response to FEMA comments and revisions as needed
Typical Deliverables
Completed FEMA application package, engineering analysis, supporting calculations, annotated FIRMs, technical narratives, and coordination with FEMA throughout the review process.
Hydraulic & Hydrologic Modeling
Advanced flood risk assessment using industry-standard methodologies
Overview
Our modeling services provide detailed analysis of flood behavior for riverine and pluvial systems. Using HEC-RAS, HEC-HMS, and other industry-standard tools, we develop accurate flood models that support regulatory compliance, design decisions, and risk assessment.
Modeling Capabilities
- HEC-RAS Analysis: 1D and 2D hydraulic modeling for riverine systems, channel improvements, and bridge/culvert analysis
- HEC-HMS Modeling: Watershed-scale hydrologic analysis and design storm development
- Floodplain Mapping: Development of regulatory floodplain boundaries and flood depth grids
- Dam Break Analysis: Inundation mapping for dam failure scenarios
- Storm Surge Modeling: Coastal flood analysis and wave effects
- Levee Analysis: Certification studies and accreditation support
Applications
Our modeling services support FEMA map revisions, infrastructure design, development permitting, mitigation planning, and regulatory compliance for projects of all scales.
Quality Standards
All models are developed in accordance with FEMA guidelines, including proper terrain representation, appropriate roughness parameters, calibration to known events where data exists, and documentation meeting FEMA quality assurance standards.
Regulatory Compliance
Expert guidance through complex floodplain regulations
Overview
Navigate federal, state, and local floodplain regulations with expert consulting services. We help ensure your projects meet NFIP requirements, local ordinances, and permitting standards while avoiding costly delays and redesigns.
Compliance Services
- NFIP Compliance Review: Verification that projects meet National Flood Insurance Program requirements
- Permit Support: Preparation of floodplain development permits and variance applications
- No-Rise Certification: Analysis and documentation that development doesn't increase flood elevations
- Substantial Improvement Analysis: Determination of regulatory thresholds for building modifications
- Local Ordinance Review: Interpretation of municipal floodplain management regulations
- Regulatory Interpretation: Clarification of FEMA guidance and technical standards
Who We Help
We assist developers navigating permitting requirements, engineers ensuring design compliance, municipalities administering floodplain programs, and property owners understanding regulatory obligations.
Floodplain Analysis
Comprehensive flood hazard assessment and mapping
Overview
Detailed floodplain studies that characterize flood risk, support development decisions, and provide defensible engineering analysis for regulatory and design purposes.
Analysis Services
- Base Flood Elevation Determination: Calculation of regulatory flood elevations for specific locations
- Floodway Delineation: Definition of regulatory floodway boundaries
- Flood Risk Assessment: Evaluation of site-specific flood hazards and potential impacts
- Freeboard Analysis: Determination of appropriate safety factors above minimum requirements
- Alternative Methods: Zone A analysis and approximate study approaches where detailed models don't exist
- Flood Storage Compensation: Analysis of fill impacts and compensatory storage requirements
Technical Approach
We utilize best available data, appropriate methodologies, and sound engineering judgment to develop analyses that are technically defensible and meet regulatory standards. Our work is documented thoroughly to support permit applications and regulatory review.
Additional Services
White-Label Support
Technical analysis and documentation delivered under your firm's brand. Maintain client relationships while accessing specialized FEMA expertise.
Technical Review & Peer Review
Independent review of flood studies, engineering reports, and regulatory submittals before FEMA submission to ensure technical accuracy and compliance.
Expert Consultation
Project-specific guidance on complex flood risk issues, methodology selection, and regulatory strategy when you need someone who has "seen it all."
Training & Capacity Building
Customized training on FEMA processes, HEC-RAS modeling, and regulatory requirements for engineering teams and municipalities. Learn more
Stormwater Engineering
Drainage design, detention/retention analysis, and stormwater management planning for development projects.
Second Opinions
Review of previous work or FEMA determinations when something doesn't seem right or when projects have stalled.
Our Partnership Approach
BaseFlood Engineering operates as a specialized resource that complements—not competes with—your existing team and local consultants. Whether you need white-label support, technical partnership, overflow capacity, or independent review, we're designed to augment your capabilities when FEMA projects get complex.
Ready to Start Your Project?
Contact us to discuss your flood risk engineering needs and learn how we can support your project.
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