MAPPING HAZARDS AND RISK

FEMA FLOOD MAPPING PROCESS

ICON Engineering, Inc.

Stormwater and Floodplain Management Specialists
- Floodplain Modeling/Mapping
- Hydrologic and Hydraulic Analysis
- Master Plans, Stream Stabilization, Restoration and Water Quality
Locally Based (Centennial, CO)
- Colorado & Front Range Clientele
- Consultant to City of Boulder & CU-Boulder
- Very Active Since 2013 Floods
FEMA DFIRMs & Letters of Map Revision (CLOMR/LOMR)
- FEMA/CWCB DFIRM Contractor
- UDFCD LOMC’s - Over 400+ Cases Reviewed

ICON Engineering, Inc.

Craig Jacobson, PE, CFM

18 Years Consulting Experience
Hydrology and Hydraulics, Master Planning Manager
LOMR/CLOMR, MT2s, Modeling Preparation & Review
Other
- Instructor: ASFPM Certified Floodplain Manager (CFM)
- Instructor: UWRI FEMA Letters of Map Change Course
- CASFM Organization: Outreach and Training Co-Chair

Eben Dennis

GIS Coordinator
Web Mapping Developer
Nerd

National Flood Insurance Program

A voluntary program based on a mutual agreement between the Federal government and the local community.

In exchange for adopting and enforcing floodplain management regulations, Federally-backed flood insurance is made available to property owners throughout the community.

National Flood Insurance Program

1968 National Flood Insurance Act

Transferred costs from the taxpayers to floodplain property owners
Provided financial aid
Guide development away from flood hazard areas

1973 Flood Disaster Protection Act

More encouragement for participation!
Flood insurance required for federally-backed loans
Limited federal disaster assistance for communities without flood insurance

NFIP Participation

National Flood Insurance Program

Biggert-Waters Reform Act 2012 / Homeowners Flood Insurance Affordability Act 2014

Reform ending subsidies for insurance
Mapping on a watershed basis

1994 National Flood Insurance Reform Act

Community Rating System (CRS)
Increased flood coverage maximum
Strengthened mandatory purchase
Mitigation Grant Program

National Flood Insurance Program

MAPPING

INSURANCE

REGULATIONS

Components of a Flood Insurance Study

Flood Insurance Study Report (FIS)

Discussion of Flooding History
Technical Analyses
Flood Discharges & Frequencies
Flood Profiles
Mapping Information

Components of a Flood Insurance Study

Flood Insurance Rate Map (FIRM)

Floodplain Inundation Limits
Flood Insurance Zones
Base Flood Elevations
Hydraulic Cross-sections
Mapping Information

Floodplain Regulation

Basis of Regulation

1% annual chance flood
100-year event
Floodway
- Theoretical boundary

“...means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot {or stricter local standard}.”

Floodplain Mapping Standards

Topography

Aerial Mapping

LiDAR

Survey

Hydrology

The quantity of water that must pass a given point

Hydraulics

The configuration and “roughness” of the channel and adjacent overbank area that must carry that water

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