Flood Plain Zone

What is a Flood Plain (FP) Zone?

The FP zone protects the public from flood hazards and preserves scenic and natural resources along rivers and streams.  The FP zone includes all areas designated as "Special Flood Hazard Areas" in a study prepared locally using local rainfall and geologic information.  Flood hazard areas are shown on maps prepared by the federal government in 1988 as a result of the county's participation in the National Flood Insurance Program.  Deschutes County is one of many organizations and agencies responsible for development in the flood plain.  For example, lending institutions require property owners to obtain flood insurance before any loan is given for development in a flood plain.  Specific standards for the FP zone in Deschutes County are found in Chapter 18.96 of the Zoning Code.  If you are considering buying a lot or building in the FP zone, you should first consult with a planner so that you are aware of special requirements involved.

What are the Flood Hazard Areas?

Areas which will be inundated by a 100-year flood event, also called the base flood, are the greatest concern.   The 100-year flood plain includes the river channel, the floodway and the "floodway fringe."  Floodway and flood plain boundaries are shown in dark gray on the flood maps; the floodway is cross-hatched.  It is important to note that the flood maps do not identify all areas subject to flooding, particularly from local drainage sources or from flood events larger than a 100-year flood.

Why isn't a house permitted outright?

As stated above, the purpose of the FP zone is to protect the public from flood hazards.  This purpose is two-fold.  While the FP zone seeks to protect individuals from the effects of flooding, the zone also seeks to serve the public good by minimizing the costs of reconstruction after a flood event.  These costs are minimized when the number of buildings permitted in the zone are limited.  This is why a house in the FP zone requires a conditional use permit.

Uses permitted outright include agricultural and forest uses, open space, residential uses that do not require structures and certain road projects. Conditional uses include single-family dwellings, agricultural accessory buildings, hydroelectric facilities, excavation/grading/fill/removal activities, subdividing or partitioning of land, expansion or substantial improvement of existing structures, boat docks and piers, and certain recreational uses.

What uses are prohibited in the FP zone?

Marinas, boat slips and boat houses are not permitted on private property. New construction is prohibited in the flood plain unless the lot is not big enough to build outside the flood plain.   If there is not enough area to build on a parcel outside the floodplain, new dwellings and accessory structures must be outside the floodway.  New parcels cannot be created which would require building within the flood plain.

Are there any special construction standards?

If a new building cannot be placed outside the flood plain, the new construction must meet specific requirements for floodproofing or elevation.  These requirements include anchoring buildings to their foundations, the use of materials and utilities which are resistant to flood damage, and elevating the building at least one foot above the 100-year flood level.  The type of construction determines which requirements apply.  In addition, expect to enlist the services of a registered professional engineer and/or surveyor for a project in the flood plain.

Are there any special setbacks?

River Setbacks :  All sewage disposal installations (septic tanks, drainfields, sand filters, etc.) and all new buildings and structures must be set back at least 100 feet from the ordinary high water mark along streams and lakes.  An exception may be granted for the building setback when a hardship exists and certain design criteria can be met [Chapter 18.120].  The Deschutes County Environmental Health Division can provide more information about setback exceptions for sewage disposal systems.

Front Yard :   A minimum of 20 feet on a local street, 30 feet from a collector and 50 feet from an arterial.

Side Yard :  A minimum of 10 feet.

Rear Yard :  A minimum of 20 feet.

Solar Setback :  The setback from a north lot line must meet solar setback requirements.

Non-farm Use :  A minimum of 100 feet is required for a non-farm use adjacent to a farm use not owned by the applicant.

Parking Facilities :  A minimum of 20 feet from the ordinary high water mark.

Can I build a dock on the river?

Boat docks and piers are allowed only with a conditional use permit in certain areas on the Deschutes River on private property.  These areas are identified by river mile so it is best to consult a planner as to whether your property is eligible for a dock or not.  There are two types of docks:  individual boat docks to serve one property owner and community docks which serve more than one owner.  An individual dock is only allowed on lots with at least 200 feet of river frontage with maximum dimensions of 20 feet by 8 feet, and an area not to exceed 160 square feet.  Community docks require at least 100 feet of frontage and cannot exceed 20 feet in length or 320 square feet in area.  Docks must not interfere with navigation on the river or impede the flow of water.  Section 18.96.080 of the County Code includes all the conditional use criteria applicable to the construction of a dock.  Permission is also required from the Division of State Lands for any work in the bed or banks of a waterway.

How do I apply?

You need to submit the correct fee and application materials in order for your application to be complete.  The Planning Division will not accept incomplete applications until the missing material is provided.

Application fee :    [ Application Forms ]  [ Application Fees ]

Application materials:

1. Completed application form
    
2. Plot Plan: 
   • Property boundaries
   • Road access
   • Setbacks
   • Location and size of existing and proposed buildings, septic system, well, exterior lighting and other improvements;
   • Existing and proposed site contours in relation to the 100-year flood elevationElevation of the lowest habitable floor for any dwelling*
   • Elevation to which floodproofing will occur, if applicable*
   • Special topographic features, including the river or stream
   • Landscape plan showing location, size and species of existing vegetation six inches in diameter or greater and vegetation to be removed
   • North arrow, scale
         * Elevations need to show distance above ground level and be referenced to mean sea level.
      
3. Written statement which explains how the proposal will meet the standards in the FP zone.
   
4. A copy of the deed showing the current ownership.