Regulatory Agency Series: Part 3
FEMA is the Secret Source for Great Flood Maps
Do you know who has the best flood information in the United States?
It’s the Federal Emergency Management Agency (commonly known as FEMA).
You may think of FEMA as the organization that messes up the government’s responses to Hurricane Katrina or Sandy.
What is FEMA?
The Federal Emergency Management Agency (FEMA) is the federal agencies that develops contingency plans for emergency disasters and coordinates and assists other federal, state, and local agencies respond to disasters.
No matter what your opinion is about how they respond to disasters, FEMA does a great job of mapping flood hazard areas in the United States.
Since the 1970s, FEMA has been creating, storing, and updating flood hazard maps for National Flood Insurance Program (NFIP) communities across the United States.
Flood Insurance Rate Maps, known as FIRMs, are the primary tool for state and local governments to identify and mitigate the effects of flooding in their communities.
FEMA produces Flood Insurance Rate Maps that show areas subject to flooding.
The flood risk information presented on the Flood Insurance Rate Map is based on historic, meteorological, hydrologic, and hydraulic data, as well as open-space conditions, flood-control works, and development.
Information on Flood Maps
A variety of information can be found on a Flood Map, including:
- Common physical features, such as major highways, secondary roads, lakes, railroads, streams, and other waterways
- Special Flood Hazard Areas (SFHA)
- Base flood elevation (BFE) or depths
- Flood insurance risk zones
- Areas subject to inundation by the 500-year flood
The Flood Map provides information that allows you:
- To identify Special Flood Hazard Areas (SFHA)
- To identify the location of a specific property in relation to the Special Flood Hazard Areas
- To identify the base (100-year) flood elevation at a specific site.
- To identify the magnitude of flood hazard in a specific area
- To locate regulatory floodways
- To identify undeveloped coastal barriers, where flood insurance is not available
Important Information For Site Inventory
Landscape architects can find a lot of valuable information about a site’s flooding potential on a FEMA flood map. The following items should be recorded during the site inventory process:
These boundaries show the 100-year and 500-year floodplains.
Hazard Area Designation
These areas appear as dark and light tints. Dark tints indicate areas of greater flood hazard; light indicates areas of lesser flood hazard.
Base Flood Elevation (BFE)
For detailed study areas this line and label indicates the water surface elevation of the base flood in relation to a standard set of geographic data in Special Flood Hazard Areas. A wavy line is used to indicate when the base flood elevation varies along a watercourse. When the base flood elevation is uniform across a large area, a label is used.
Flood Insurance Risk Zone Designations
The zone designations indicate the magnitude of the flood hazard in specific areas of a community.
This line identifies the location of a watercourse. Narrower streams are usually shown by a single line, representing the approximate location of the stream centerline. Wider streams are often shown by double lines, representing stream bank locations.
Why is FEMA Important for Landscape Architects?
FEMA is important to landscape architects because they produce the most authoritative and comprehensive series of flood hazard maps.
During the site inventory process, you can use FEMA flood hazard maps to determine if your project site is located within a flood plain.
FEMA maps also may indicate the 100 year flood level elevation. Most municipalities require building finished floors to be located above the 100 year flood elevation.
Flooding and siting landscape features in the flood plain are important safety issues that landscape architects must take into considerations when planning landscapes and planning a site.
Expect a few questions about flooding and flood maps on the California Supplemental Exam (CSE) for landscape architects.
Get FEMA Flood Maps
If you want to check out a real FEMA flood map, you can view and download them from FEMA’s Map Service Center (http://www.msc.fema.gov/).
For More Information on Regulatory Agencies:
- Part 1: Introduction to Regulatory Agencies on the California Supplemental Exam
- Part 2: US Army Corps of Engineers
- Part 3: Federal Emergency Management Agency
If you are looking for a study guide to help you prepare to pass the CSE the first time, check out Pass the California Supplemental Exam for Landscape Architects study guide e-book.