At the conclusion of this lesson, for individual map panels, you will be able to:

• Recognize elements found on most individual Map Panels
• Recognize elements found on some Flood Boundary and Floodway Maps (FBFMs) or Flood Insurance Rate Maps (FIRMs)
• Recognize elements found only on Countywide flood map Panels

When a flood map cannot be presented on one page, it is produced on several pages known as Panels. Flood Map Panels depict the flood hazards in different parts of a community.

Scroll down to see slideshow captions.

There are additional elements that may be found on nearly all flood map Panels. Newer maps may not include all of these elements:

• Floodplain Boundaries
• Hazard Area Designation
• Base Flood Elevation
• Flood Zone Division Line
• Flood Insurance Risk Zone Designations
• North Arrow
• Stream Lines
• Coastal Barrier Symbol
• Area Not Included Label
• Map Scale
• Panel Number
• Notes to User
• Elevation Reference Marks (ERMs)

Each element will be discussed in further detail on the following screens.

Floodplain boundaries show the 1-percent (100 year) annual chance and 0.2-percent (500 year) annual chance floodplains.

The shade and pattern indicate areas of different flood hazard and the flood zone.

*Note - see map legend for listing of all flood map hazard area shades and patterns with appropriate zone designation.

(on newer maps the lighter gray Zone B area below indicating the 0.2% (500 year) floodplain area and the white Zone C area will both be listed as Zone X)

For detailed study Special Flood Hazard Areas (SFHAs) this label indicates the water surface elevation of the base flood, rounded to the nearest foot, in relation to a standard set of geographic data.

A wavy line is used to indicate when this rounded base flood elevation varies along a watercourse (Typically Riverine AE zones).

When the rounded base flood elevation is uniform across a large area, a BFE label below the zone label is used (Typically Ponding AH, Lacustrine (Lake) AE, and Coastal AE and VE zones).

Remember, you must refer to the Flood Insurance Study Profile to get the actual BFE for floodplain management and flood insurance purposes.

This white line separates Special Flood Hazard Areas with different zone designations. It is also used to separate Special Flood Hazard Areas with differing Base Flood Elevations in coastal hazard areas.

*Flood Zone Division Line is also used to indicate the "Limit of Detailed Study" which is the dividing line between Zone AE and Zone A.

This line may also be called the Zone Break Line or Zone Boundary Line.

The zone designations indicate the magnitude of the flood hazard in specific areas of a community.

A Special Flood Hazard Area (SFHA) is defined as the area that will be inundated by the flood event having a 1-percent chance of being equaled or exceeded in any given year.

SFHAs are labeled as:

• Zone A
• Zone AE and Zones A1-30
• Zone AO
• Zone AH
• Zone AR, AR/A1-30, AR/AE, AR/AH, AR/AO, and AR/A
• Zone A99

SFHAs subject to coastal high hazard flooding are designated V Zones:

• Zone V
• Zone VE and Zones V1-30

Moderate Flood Areas

Moderate flood hazard areas, labeled Zone B or in newer FIRMs as Zone X (shaded) are also shown on the FIRM, and are the areas between the limits of the base flood and the 0.2-percent-annual-chance (or 500-year) flood.

Minimal Flood Areas

The areas of minimal flood hazard, which are the areas outside the SFHA and higher than the elevation of the 0.2-percent-annual-chance flood, are labeled Zone C or in newer FIRMs as Zone X (unshaded)

Zone D: Area of undetermined but possible flood hazard.

This arrow orients the flood map to north.

Note: On older map sets the north arrow may not be oriented to the top of the map panel.

Stream lines identify the location of a watercourse.

Narrower streams are usually shown by a single line, representing the approximate location of the lowest elevation of the stream (centerline or thalweg).

Wider streams are shown by double lines, representing the location of the top of the stream banks.

These symbols identify coastal areas in the Coastal Barrier Resources System (CBRS) and Otherwise Protected Areas (OPAs).

CBRS zones are designated by the US Fish and Wildlife Service. No new flood insurance coverage may be provided after specified dates for new or substantially improved structures on any Coastal Flood Hazard Area in the CBRS.

OPAs are a category of coastal barriers within the CBRS. OPAs are undeveloped coastal areas established under Federal, State, or local law, or held by a qualified organization, primarily for wildlife refuge, sanctuary, recreational, for natural resource conservation purposes. Flood insurance is restricted in OPAs, though OPAs may receive other forms of Federal assistance. OPAs are identified on FEMA FIRMs.

Note: New FIRM panels will no longer include designated CBRS zones. However the National Flood Hazard Layer (NFHL) Viewer displays this information.

This label identifies areas that are in the Panel area but are not in the jurisdiction of that community; thus, no flood hazard information is shown in that area

This allows you to relate distances measured on the flood map to actual distances on the ground. The scale shown on a Panel applies only to that Panel. Scale ratios can vary from panel to panel. The most commonly used scales on flood maps are one inch on the map equals 500, 1000, or 2000 feet on the ground.

This number distinguishes each Panel from others in the same community; each page is given a unique Panel number. On FHBM, the Panel number is a two-digit number. On FBFM/FIRM the Panel number is a four-digit number.

Panel Number/Community – Panel Number/Map Number

Different types of numbers appear on flood map title boxes prepared in different formats. Each type of number identifies the Panel that covers an indicated portion of the community.

On FIRM title boxes, the first set of numbers identifies the community or countywide ID number. The second set of numbers identifies the Panel number. The trailing letter after the panel number corresponds to the number of map revisions.

On Indexes, the second set of numbers corresponds to the range of printed Panels.

The entire 11-digit code for each Panel is required to identify a Map Panel. The Panel number includes the 6-digit CID or the 5 digit CWID followed by the letter "C" and the Panel number, as well as a letter suffix (which indicates the map revision number).

In this FIRM title boxes, the first set of numbers is the countywide ID number. The second set of numbers identifies the Panel number. The trailing letter is the number of map revisions.

These notes provide additional information to clarify zone designations or special notes on the use of the flood map.

Other examples of Notes to User:

• Information on Horizontal and Vertical Datum.
• Certain areas not in the special flood hazard areas (Zone A and V) may be protected by flood control structures.
• This map is for flood insurance purposes only; it does not necessarily show all areas subject to flooding in the community or all planimetric features outside special flood hazard areas.
• For adjoining map panels, see separately printed Index To Map Panels.

Click Datum to open the definition in a new widow.

Elevation Reference Marks (ERMs) identify points where a ground elevation was established by survey. These elevations are usually expressed in feet; elevations in Puerto Rico are expressed in meters. Descriptions of the marks, including their elevations, are provided.

Scroll down to see slideshow captions.

The descriptions of the ERM locations appear in different places, depending on the format of the flood map, as seen in the table below.

Marks included on many FIRMs are temporary in nature and may not be recoverable. To obtain current elevation, description, and/or location information for other bench marks for the FIRM, you can use the National Geodetic Survey Data Explorer available at https://www.ngs.noaa.gov/NGSDataExplorer/ or you may contact the Information Service Branch of the National Geodetic Survey at http://www.ngs.noaa.gov or by telephone at 301-713-3242.

Panel elements that may be found only on some FBFM/FIRM Panels include:

• Alpha-numeric Grid

Elements that will be found on FBFM panels, but not FIRM panels, in the pre-1986 FIRM/FBFM map sets include:

• Cross Section Symbol
• Floodway Boundaries
• Floodway Designation

The Alpha-numeric Grid is the basis of the coordinate systems established for the Floodprone Street Index.

These elements will be found only on FBFM panels in the pre-1986 FIRM/FBFM map sets. They are not on the Pre-1986 FIRMs.

• Floodway Boundary Lines
• Cross Section Symbols
• Floodway Area Designation

The floodway is the channel of a river or other watercourse, plus any adjacent floodplain areas that are reserved, so that the 1-percent annual chance flood discharge can be conveyed without increasing the elevation of the 1-percent annual chance flood more than a designated height.

Elements found only on some FBFM/FIRM Panels include:

• Community Panel Number
• Initial Identification Date
• Flood Hazard Boundary Map (FHBM) Revisions Chronology
• Map Effective Date

Each element will be discussed in further detail on the following screens.

The Community Panel Number identifies the community with the first six digits and the Panel with the last five.

It corresponds to a community Panel number shown on the Index.

On the FIRM, the letter suffix following the panel number indicates the number of times the map panel has been reissued. The number 0038D in the example indicates that panel #0038 has been issued 4 times.

This date appears in the legend and indicates when the flood hazards in the mapped community were first identified.

Flood Hazard Boundary Map (FHBM) Revisions Chronology lists the dates of revised versions of the Flood Hazard Boundary Map (FHBM) for the community.

When the FHBM is updated, it is typically converted to a FIRM format.

The Map Effective Date appears in the legend. It indicates when that specific Flood Map panel became effective.

Elements found only on Countywide Panels include:

• Effective Date on Countywide Map
• Map Number

Each element will be discussed in further detail on the following screens.

This is the date on which the Countywide Flood Map first became effective.

Flood Maps may have been in effect for one or more of the individual communities in the county before the countywide Flood Map was published.

This number identifies the Panel.

It is composed of a five-digit code that identifies the county; a letter "C" that indicates countywide mapping; and a four-digit number corresponding to the Panel number followed by a letter suffix that indicates the number of times a Panel has been revised.

You have just completed Lesson 4, which:

• Floodplain Boundaries
• Hazard Area Designation
• Base Flood Elevation
• Flood Zone Division Line
• Flood Insurance Risk Zone Designations
• North Arrow
• Stream Lines
• Coastal Barrier Symbol
• Area Not Included Label
• Map Scale
• Panel Number
• Notes to User
• Elevation Reference Marks (ERMs)

• Alpha-numeric Grid
• Cross Section Symbol
• Floodway Boundaries
• Floodway Designation

• Initial Identification Date
• FHBM Revisions Chronology
• Map Effective Date

• Effective Date of Countywide Map Panel
• Map Number