Floodplain regulations update
for consistency with the National Flood Insurance Program

Notice of determination of non-significance under the State Environmental Policy Act (SEPA)

King County Water and Land Resources Division has issued a determination of non-significance (DNS) under the State Environmental Policy Act Rules (Chapter 197-11 WAC) for the following project: an ordinance amending floodplain regulations for consistency with the National Flood Insurance Program proposed by the River and Floodplain Management Section. After review of a completed environmental checklist and other information on file with the agency, the Water and Land Resources Division has determined this proposal will not have a probable significant adverse impact on the environment. View the Determination of Non-Significance and Environmental Checklist online (Acrobat pdf) or request copies  by calling 206-296-6519.

The public is invited to comment on this determination of non-significance by submitting written comments no later than Monday, June 8 at 5:00 PM to wlrfloodc@kingcounty.gov or by mail to:

King County Water and Land Resources Division
River and Floodplain Management Section
201 South Jackson Street, Room 600
Seattle, WA 98104-3855

The Washington State Department of Ecology, acting on behalf of the Federal Emergency Management Agency (FEMA), conducted a Community Assistance Visit (CAV) in January 2009 and found deficiencies relating to performance standards for the AO (shallow flooding) flood zone. In addition, King County flood regulations allow a professional engineer to prepare a FEMA Elevation Certificate but should only allow a Professional Land Surveyor to prepare Elevation Certificates. View the draft ordinance online (Acrobat pdf) or request copies by calling 206-296-6519.

The amendments contained in the draft ordinance are summarized as follows:

Section 1, lines 59-60 – this would allow King County to exclude the costs to elevate a residential structure when determining if the project is considered a substantial improvement. This section may be dropped based on a pending decision from the FEMA Headquarters.

Section 2, lines 99-100 – this change would allow King County to use whatever data accurately classifies and delineates flood hazard areas or base flood elevations. This is added to allow King County to utilize underlying data used in creating flood hazard maps for determining a base flood elevation for the AO (shallow flooding) flood zone. The AO flood zone does not establish a base flood elevation like other flood zones, and the data needed to establish a base flood elevation, such as the topography, is not be included in the preliminary or adopted maps or studies or any of the other sources of flood hazard data listed in this section of code.

Section 3, lines 115-117 – this would allow fill to be placed within the foundation of an existing residential building to the level of the lowest adjacent grade without providing compensatory storage. This area below the lowest adjacent grade is considered “dead storage” so fill placed there will not have an impact on the storage capacity of the floodplain. Relief from compensatory storage will facilitate the ability to eliminate sub-grade crawl spaces, which are not allowed under King County code and which were one of the more common floodplain development violations identified through the CAV.

Section 3, lines 291-295 – this provision related to uses not allowed during the flood season was located in the zero-rise floodway (K.C.C. 21A.24.250) but is being relocated to the zero-rise flood fringe (K.C.C. 21A.24.240) to assure the provisions apply to the AO flood zone.

Section 4, lines 323-327 – this is the section relocated to the zero-rise flood fringe. See above.

Section 5, line 376 – this removes the ability for a civil engineer to prepare an Elevation Certificate. The Washington State Board of Registration for Professional Engineers and Land Surveyors has determined that only Land Surveyors should be able to prepare FEMA Elevation Certificates.

Section 5, line 381 – this change simply moves the requirement for the surveyor to identify if a structure has a basement up to subsection A of this section that specifies what the land surveyor must document.

Comments on this draft ordinance must be received no later than Monday, June 8, 2009 at 5:00 PM. For additional information, please contact Priscilla Kaufmann, Project Manager at (206) 205-0598 or Priscilla.kaufmann@kingcounty.gov, or by mail: Water and Land Resources Division, 201 S. Jackson St., Suite 600, Seattle, WA 98104.