Text Size:   A+ A- A   •   Text Only
Site Image

Floods: Property Owners and Developers
This section covers how to read a flood hazard map, how to obtain a flood hazard map, floodplain insurance, permits for work in the floodplain, determinations that property is in or outside the floodplain, avoiding and limiting flood damages, and technical guidance on various floodplain management issues.

Reading a Flood Map/Obtaining A Flood Map
FEMA has created flood hazard maps for all communities (cities and counties) in Oregon that are potentially affected by flooding. These FEMA maps are called "Flood Insurance Rate Maps (FIRMS)" and Floodway maps.
FIRMs and floodway maps are used by local communities and state agencies to identify areas subject to floodplain regulations. Insurance agents and lending institutions also use FIRMS to determine flood insurance needs and rating. The flood hazard information contained on these maps is based on historic flooding, hydraulic and hydrologic data, flood control projects, and other factors that impacting flooding.
FEMA maps contain a variety of information such as:
  • Boundaries of the 100-year floodplain (i.e., the area in which there is a 1% risk of flooding in any given year)
  • Flood water elevations (i.e. depth) for the 100 year flood
  • Floodways (i.e., area reserved to carry high velocity flood waters)
  • Physical Features such as highways, streams, etc.
  • Flood Insurance risk zones
To learn about how to read a FEMA Map, you may want to try FEMA’s on-line tutorial.
FEMA maps for your community should be available for review at your local planning department and perhaps also at your local library. You can also obtain copies of FEMA maps through the FEMA Flood Map Store.
Please be advised that digital maps, known as DFIRMS, have been created for some Oregon communities. DFIRMS provide the same basic information as the paper FIRMS, and sometimes more, but in a digital format.

Floodplain Insurance
Your city or county’s agreement to adopt and enforce floodplain management regulations, particularly with respect to new construction in the floodplain, is the key to making flood insurance available to home and businesses owners in your community. Without local government participation in the NFIP, flood insurance would essentially not be available to those in your community. Private insurance companies tend to only offer flood insurance under the umbrella of the NFIP.
Information on flood insurance can be obtained from FEMA or your local insurance agent. Or you can click here for background information on flood insurance.
Please be aware that neither state or local government is directly involved with flood insurance, i.e. selling of policies, determination of risk, setting of rates, requiring purchase, etc. However, your lender may require purchase of flood insurance if you have or are requesting a federally-backed mortgage or for other reasons. Any disputes with your lender about flood insurance requirements will need to be taken up directly with the lender.

Permits and Other Approvals in Flood Hazard Areas
Local governments participating in the NFIP are required to regulate development in floodplains. Under the NFIP, the term development is defined broadly and includes:
"Any man-made change to improved or unimproved real estate, including but not limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations located within the area of special flood hazard."
There are minimum standards that local regulations must include. To learn more about what local governments must require in flood hazard areas, see also the Floods-Local Government section . Communities can adopt more stringent standards if needed to address flood hazards in that area.
You will need to consult with your city or county planning department prior to conducting any development activities in the floodplain to determine if a local permit is needed. If a local permit is required, your planning department will advise you of the information, application forms, and fees that must be submitted to process the permit. The planning department can also point you to the applicable floodplain regulations. If you are having difficultly finding the appropriate local contact, then please contact the department, and we will assist you.
Remember that in addition to a local permit, you may also need a state and/or federal permit if your proposed work will involve a waterway or wetland.

Determination that Your Property is Within a Flood Hazard Area
Siletz River Flood (1999)
Your lender or local government has notified you that your property (land or structure) is within a mapped, flood hazard area. Perhaps you have reviewed the flood hazard maps for your community and disagree. In such cases, many property owners call DLCD or their local governments to ask how they can challenge the determination that their property is within a flood hazard area. Since neither the state nor local government can modify NFIP flood hazard maps, the answer is that you will likely need to request review of your situation by FEMA.
FEMA has procedures in place for their review of requests to determine that a property (land or structure) is outside a flood hazard area. You may want to look into the FEMA procedures for requesting a Letter of Map Amendment (LOMA) or Letter of Map Revision based on Fill (LOMR-F). FEMA has information available on its website about these procedures:
Again, remember that neither DLCD nor your local government has authority to approve LOMAs or LOMR-Fs.

Avoiding and Limiting Flood Damages
There are a number of things that you can do to avoid and limit flood damages to your property.
If you have an existing home or business in the floodplain, you may want to review the Emergency Preparedness section of DLCD’s Natural Hazards website to learn about what to do before, during, and after a flood.
If you are looking to purchase land and/or build a new home or business, then you may want to check with your local government to determine if the property is within the floodplain.
You should also talk with your local government, DLCD or your developer about ways new development can be located or designed to avoid potential impacts from flood hazards.
If you are looking to purchase an existing residence or other building, you should check with your local government to determine if it is within the floodplain and inquiry with the current owner about any measures taken in the construction or repair of the building to address flood hazards (e.g. is the structure elevated, flood-proofed, has it experienced past flood damages.).
For existing structures within the floodplain, you may also want to hire a reputable building inspector to check for signs of past flood damage prior to purchase.