New "L" Series FEMA Flood Insurance Rate Maps

Table of Contents

• Overview
• When will the new FIRMs become effective?
• What is the 100-year floodplain?
• Flood Insurance
• Locally Mapped Flood Hazards
• Viewing FIRMs and DFIRMs
• What it means if your property has been removed from the mapped 100-year floodplain: Flooding is still a possibility.

Overview:

Periodically, the Federal Emergency Management Agency (FEMA) issues new Flood Insurance Rate Maps (FIRMs) and a new Flood Insurance Study (FIS) for a community. This is done to incorporate changes in political boundaries, Letters of Map Revision (LOMRs) and Letters of Map Amendment (LOMAs) that have been added to the existing FIRMs, and add new information that is available. The individual FIRM maps, called panels, are what lenders use to determine if a structure is in a Special Flood Hazard Area (SFHA). They are used to determine whether flood insurance is required, and how much flood insurance coverage will cost.

FEMA is preparing to make new FIRM panels effective for all of Pima County. The "K" series FIRMs will be replaced by the new "L" series of Digital Flood Insurance Rate Maps (DFIRMS).

The Preliminary DFIRM data presented here is subject to modifications based on the review comments and data that FEMA receives and the continual processing of map revisions that will occur prior to the Preliminary DFIRMs becoming effective. Changes resulting from the comments and appeals FEMA recieves will not be known until one to two months before the effective date of the Preliminary dFIRMS. Local floodplain jurisdictions have already had a chance to submit comments on the Preliminary DFIRMS to FEMA. It is not known which of those comments, if any, FEMA will accept and incorporate into the Preliminary DFIRMs.

The Preliminary DFIRMS incorporate a number of updates and corrections, namely:

• Most LOMRs that were attached to the "K" series FIRMS will be incorporated into the Preliminary DFIRMs. the Summary of Map Actions (SOMA) tables show which map actions are being incorporated into the preliminary maps.
• The vertical datum for elevation data has been updated from the National Geodetic Vertical Datum of 1929 (NGVD29) to the North American Vertical Datum of 1988 (NAVD88).
• An aerial photograph background has been added to the DFIRM panels to assist in determining whether structures are located in or out of the floodplain.
• Minor corrections have been made in some locations where better topographic data has revealed obvious errors in floodplain delineations.
• Incorporation of the concept of "Provisionally Accredited Levees" (PALs). PALs are levees that are expected to conform to FEMA minimum standards of flood protection, but for which there wasn't enough readily available data to demonstrate conformance, and for which there was not enough time prior to the creation of the maps for the entity maintaining the levee to obtain the necessary information to demonstrate conformance. These areas are indicated on the DFIRMs, and are not considered a SFHA at this time, but will be considered as a SFHA if FEMA does not accept the the levee as meeting the minimum standards for flood protection.
• The Town of Marana submitted a map revision application to FEMA to address the flooding impacts form the Tortolita Fan, Interstate 10, the Union Pacific Railroad and the Central Arizona Project aqueduct.   The majority of the changes are within the Town of Marana, but some unincorporated areas of Pima County are also impacted.  For more information on this floodplain re-mapping visit Marana's website http://www.marana.com/index.aspx?NID=592

To aid understanding of how the Preliminary DFIRMs may affect you, the District has developed a Frequently Asked Questions brochure (PDF format). Please see the Relevant Links section in the right column for links to other important information.

FEMA projects that the effective date for the new DFIRMs will be August 29, 2010. However, there are multiple factors that may delay the effective date for printing and publishing the DFIRMs. These include map appeals, map protests and Federal Register timing issues. Since the projected date could change, check back to this website for updates to the effective date of the DFIRMs.

The DFIRMs primarily show what is often called the 100-year flood, a misleading term for a flood that has a 1 (one) percent chance of occurring during any given year. A more appropriate term is the 1-percent chance flood, also known as the base flood, because the "100-year" flood can occur two years in a row, or even twice in the same year. FEMA calls areas subject to the 1-percent chance flood "Special Flood Hazard Areas" (SFHA). Be aware the DFIRMs do not show all the “100-year” floodplains in Pima County.  Contact your Local Floodplain Jurisdiction for additional floodplain information in your area.

FEMA designates different types of floodplains with different identifiers. Please see the FEMA flood zone descriptions page for more information.

Flood Insurance:

Although the Flood Disaster Protection Act of 1973 requires federally insured lenders to have flood insurance on loans with structures in a federally map floodplain, all property owners are encouraged to review the existing FIRMs and Preliminary DFIRMs to determine if and how any changes might impact them. It is important for property owners who are affected by the current and/or proposed flood hazard mapping to review the maps carefully, as potential changes can have serious ramifications. For example, if a house is currently not mapped in a FEMA Special Flood Hazard Area (SFHA) but will be mapped in an SFHA on the DFIRMs, the property owner can purchase flood insurance BEFORE the new mapping becomes effective (date unknown) and pay much less for the flood insurance than would be required if the policy is obtained AFTER the new mapping becomes effective.

In other words, if the policy is purchased before the new mapping becomes effective, the pre-SFHA insurance rate would apply even after the house or business has been mapped into the floodplain, potentially saving the property owner hundreds or thousands of dollars a year. Moreover, it is possible to transfer the insurance rate in escrow to a new owner, making the property more affordable to potential buyers. For more information on flood insurance, please visit the "Relevant Links" in the right side-bar of this page.

Visit FloodSmart.gov or talk to an insurance agent to obtain flood insurance premium estimates for your property. You may also wish to read the FEMA Frequently Asked Questions sheet on how revised flood hazards effect existing structures.

Locally Mapped Flood Hazards:

It is important to note that the FIRMs do NOT show locally determined flood or erosion hazard areas. If your property is not in a FEMA floodplain as shown on the FIRMS, it may be in a locally regulated floodplain or erosion hazard area. Please contact your local jurisdiction to determine your local floodplain status. Within unincorporated Pima County, you may view a Flood Hazard Map which shows all currently mapped floodplains. This map does not show erosion hazard areas, and is not a guarantee that your property isn't subject to flood and/or erosion hazards, as there are hazards that have not yet been identified and mapped by the District.

In order to provide the greatest level of accessibility to the public, the District has made the current "K" series FIRM and Preliminary "L" series DFIRM panels available for review in a number of ways.

• Hardcopies (FIRMs and DFIRMs) are available through each local jurisdiction, which is the local map repository for flood maps in that jurisdiction (i.e. City of Tucson, Town of Marana, Unincorporated Pima County, etc.)
• FIRM Panel Review Parcel Information. The search function below will take you to a page that contains your parcel information and provides the following information:
• Existing and Preliminary FEMA Flood Hazard Area. Please note that these results are for the entire property, while insurance requirements are based on the flood hazard zone(s) impacting the insurable structure(s) on the property. It is possible for a property to be partially in a floodplain while the structure is outside of the floodplain. Only a review of the maps can be used to determine if your structure is in the floodplain or not.
• DFIRM panel number, which includes a link to the official FEMA PDF of the L-Series DFIRM panels.
• Link to a MapGuide map, zoomed to your parcel, showing the existing and preliminary floodplain information.

Street Address Number Search	Enter just the street number. Then pick a button by the desired street address in the search results.
Parcel Code Search	Enter 8 digit numeric and last digit alpha/numeric for a total of 9 places in the parcel code {BookMapParcelSplit}. An 11 character formatted value with dashes may also be used. For example: 11711001B or 117-11-001B

 

• Digital PDF files (DFIRMs only). NOTE: These files are reachable through the search function above, the use of which is recommend if you don't know which DFIRM Panel your property is on.
• FIRM Panel Index, DFIRMs of 2010 Compared to 1999 FIRMs (3.5 megabytes)
• DFIRM Map Index (1.2 megabytes)
• DFIRM Maps - Web friendly file sizes (Each 1.5 to 3 megabytes)
• DFIRM Maps - Original LARGE files (Best quality. Large files, 10 to 50 megabytes each.)
• Floodplain Review MapGuide Map application with side-by-side comparison and search functions (FIRMs and DFIRMs). Read the Disclaimer and Using Autodesk MapGuide.
• The map shows two map frames with the current data on the left and the preliminary data on the right. The maps are "geo-linked". That is, zooming and panning the left map changes both map views. For best viewing maximize your browser window to fill your screen. If you have two monitors, we suggest stretching the browser window to fill both screens. If you have a little screen space to spare, you may want to expand the legends by dragging the right legend edge to make it easier to see the layer names. You can always see full legend layer names by hovering the mouse cursor over the names.
• To have the yellow map tip information display FEMA flood hazard zone information instead of showing parcel information when the mouse is hovered over the map, turn the parcel layer off using the checkbox in the legend or the checkboxes above the map windows. The parcel layer (as well as all other layers) on each map frame can be controlled independently.
• FEMA designates different types of floodplains with different identifiers. Please see the FEMA flood zone descriptions page for more information.
• Aerial photo coverage - The DFIRMs utilize a mixture of three different aerial photo coverages. Most of eastern Pima County is covered by 2002 aerial photographs which was the most up to date coverage when this process was started. Most of the rest of Pima County is covered by 2006 aerial photographs, except for areas around the Town of Ajo, which utilize 2005 aerial photographs. These layers are on automatically on the MapGuide map, but other aerial photography layers are available and more recent aerial photography may be useful in areas that are recently developed. However, it is important to note that the aerial photographs noted above are what are used on the official DFIRMs and are therefore the regulatory standard.
  

What it means if your property has been removed from the mapped 100-year floodplain: Flooding is still a possibility.

Being outside of a Special Flood Hazard Area on a FIRM panel is absolutely NOT a guarantee that your house or property will not flood.

To begin with, the DFIRMs do not show all areas subject to the 1 percent chance ("100-year") flood. The DFIRMs only reflect major floodplains. Some properties are adversely impacted by tributary flow or by local drainage not reflected on the federal maps. Your local jurisdiction likely has mapped flood hazards that FEMA does not show on the DFIRMs.

It is also very important to realize that the floodplain delineations on the DFIRMs are lines on a map, and, just as floods don't look at calendars to know when to occur (see "What is the 100-year floodplain?"), floods don't read maps. While FEMA uses the best available data in creating the maps, variations in the intensity or duration of rainfall, small variations in ground topography, and other factors can have significant impacts on whether a house near the mapped floodplain boundary will be safe from flooding or not.

In addition, storms do occur that have intensities greater than the 1-percent chance event. In addition, changes in river or watershed characteristics could increase flood depths and discharges. The Shaded Zone X designation may also represent areas of shallow flooding (less than one foot) during a 1-percent chance event.

Just because your house or business is outside of the mapped floodplain does not mean your house will not flood, even during the base flood that FEMA and local jurisdictions regulate to, let alone during the larger flood events that they do not regulate to.

For these reasons, the District recommends flood insurance for all properties in or near floodprone areas. For those properties outside of the SFHA, flood insurance is inexpensive, and while it is a bit more expensive in SFHAs, flood insurance is invaluable if disaster strikes.

It is important to realize that your homeowners or renters insurance will NOT cover your property or belongings in the event of a flood.

Explanation of Floodplain Change Areas layer in MapGuide application:

The MapGuide application contains a layer called Flood Hazard Zone Difference Areas and a layer called Floodplain Change Areas. The Flood Hazard Zone Difference Areas layer shows the locations where there is any kind of difference between the effective FIRMs and the Preliminary DFIRMs. The Floodplain Change Areas layer shows not only the locations where there is any kind of difference between the effective FIRMs and the Preliminary DFIRMs, but also describes what type of change is occurring. Below is an explanation of terminology used in the Floodplain Change Areas layer.

• ADDED-SFHA - Areas shown in red are areas that are within a Special Flood Hazard Area (SFHA) on the Preliminary DFIRM that are not in an SFHA on the effective FIRM. This includes areas of new mapping and areas where the floodplain boundary has expanded.
• CHANGE-NONSFHA - Areas shown in light green are areas in which there has been a change from one non-SFHA zone to a different non-SFHA zone, for example a change from Zone X (Shaded) to Zone X (unshaded).
• CHANGE-SFHA - Areas shown in blue are areas in which there has been a change from one SFHA zone to a different SFHA zone, for example a change from Zone A to Zone AO1
• NO CHANGE - Areas shown in yellow are areas in which there has been a change from one SFHA AO zone to a different SFHA AO zone, for example a change from Zone AO1 to Zone AO2.
• REMOVED-SFHA - Areas shown in green are areas in which there has been a change from an SFHA zone to a non-SFHA zone, for example a change from Zone AE to Zone Shaded X. It is important to note that while a change of this type may remove the federal insurance requirement, the resulting floodplain may still be regulatory according to the local jurisdiction, and you should check with your jurisdiction to determine whether any restrictions to development exist.