Flood image via FloodSmart.gov


FEMA Flood Maps

Flood insurance is part of living on the coast of Maine. Recently we have heard concerns about changes to FEMA flood maps and insurance rates from island and coastal community residents. Flood insurance represents a growing and significant cost to coastal property owners. Some of the changes in flood insurance maps may also make it more difficult for owners of working waterfront and coastal properties to upgrade their infrastructure or sell their property. 

We have developed a list of resources for communities and residents to answer questions on this issue. Contact information can be found in the Resources section,

If you’re concerned about how mapping changes impact your property, start with this:

  • Compare the former map to the new map to get a sense of the change in base flood elevation or the status of the area such as a new velocity zone. You can see the maps at FEMA's website: https://msc.fema.gov/portal
  • Draw a diagram to show where structures are positioned on your property in relation to the lines on the map.
  • Contact your local government (e.g. board of selectmen, city council) to request changes to the maps, point out inaccuracies, and ask for assistance in remedying errors. 

For more information on the meaning of flood risk statuses (such as VE or AE, B, C, or X) consult FloodSmart.gov

For information on how to request a change to your flood risk designation, visit http://www.fema.gov/change-flood-zone-designation-online-letter-map-change.

To find out where your community is in the process of updating flood maps, contact your local town officials. The Maine Flood Plain Management Program also has a number of valuable resources for communities http://www.maine.gov/dacf/flood/mapping.shtml


The National Flood Insurance Program (NFIP) identifies areas that are at a higher risk for flooding. The NFIP offers subsidized flood insurance for homes and businesses in these areas and fills a gap in the insurance market that private insurers are not participating in because the losses outweigh the premiums generated. For homes and businesses in areas designated as being at a high risk for flooding, flood insurance is required by many lenders. According to FEMA “Lenders are mandated to require the purchase of flood insurance by property owners who acquire loans from federally regulated, supervised, or insured financial institutions for the acquisition or improvement of land, facilities, or structures located within or to be located” within the identified flood plain.

Participation in the NFIP requires a community to adopt and enforce local floodplain management ordinances. These ordinances are designed to help reduce the risk to property owners of building in a flood zone by requiring either modifications to structures or outright prohibiting building or rebuilding in certain areas. The NFIP rates are not based on actuarially sound insurance principles and large storm events over the past decade have driven the program $24 billion into debt. 

Recent Congressional legislation tried to put the program on an actuarially sound basis—meaning that premiums paid in would cover the anticipated losses. Parts of the legislation have been put on hold or slowed down to ease the burden to property owners of significant increases in flood insurance premiums. See the Resources section for more information.

Updating the Flood Maps

Some of Maine’s coastal counties are undergoing an update to the flood insurance rate maps. The maps form the basis for identifying properties that are at risk of flooding and define the “Special Flood Hazard Area” which is “a high-risk area defined as any land that would be inundated by a flood having a 1-percent chance of occurring in a given year.” 

According to FEMA,

"[The SFHA] standard constitutes a reasonable compromise between the need for building restrictions to minimize potential loss of life and property and the economic benefits to be derived from floodplain development. Development may take place within an SFHA, provided that development complies with local floodplain management ordinances, which must meet the minimum Federal requirements. Flood insurance is required for insurable structures within high-risk areas to protect Federal financial investments and assistance used for acquisition and/or construction purposes within communities participating in the NFIP.”

The updates to the flood maps in Maine are occurring because the current maps for many communities were developed in the mid-1970’s or early 80’s. Changes to the maps may mean that property owners are required to purchase flood insurance. There are processes in place to help clarify the risk of a flood to a specific property or community but these processes can be expensive, time consuming, and ultimately the maps will remain risk-based. 

Recent efforts to update the flood maps mean that many coastal residents are seeing new or significantly escalating costs to their exiting flood insurance premiums or are finding themselves squeezed as they go to refinance, upgrade or sell their properties. 

Challenges to FEMA Maps

There are a number of difficulties involved with challenging FEMA’s maps.

First, the maps are risk-based and must be based on the best available science. FEMA is interested only in whether its estimate of flooding risk is accurate or not. Economic impact, hardship, and evidence that the property hasn’t flooded in the last 300 years do not provide a solid (or likely successful) basis for challenging the maps. 

For individual homeowners, there are generally two different questions to ask before requesting that FEMA change a flood status:

  1. Is the map “right”? Does it show water crossing contour lines in ways that water cannot flow?
  2. Does an additional level of detail about the topography of the land clarify whether a home or structure is not in the flood plain? If the structure on a property is safely outside the flood plain, FEMA may reconsider a flood status designation. 

During the process of adopting the maps, some communities have successfully argued to FEMA that the data being put into the model is wrong. For example, if FEMA assumed a high wind speed and a long term data series shows that, in fact, the 1 in 100 year storm would have lower winds (and therefore wave action and coastal flooding would be diminished), FEMA could reconsider its flood status designation. In order for this argument to work, it is necessary to have the underlying data. 

In addition, some communities have successfully challenged the underlying model used by FEMA to determine the maximum wave size in coastal areas. At least some of FEMA’s models ignore offshore reefs and other aspects of bottom topography that can have a significant impact on wave height. Again, this process requires a new model that is grounded in science and can be shown to be more accurate than the model FEMA originally used.