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Development in Many Areas Severely Restricted by New Floodplain Maps

Owners of billions of dollars worth of property in Washington State will see severe curbs on development once the revision of the countrys floodplain maps is completed by the Federal Emergency Management Agency (FEMA).

FEMA is revising the floodplain maps in support of the National Flood Insurance Program (NFIP). The intent of the NFIP is to reduce future flood damage through community floodplain management and to provide protection for property owners against potential flood related losses through insurance rather than relying solely on emergency relief programs. FEMA considers the floodplain to be the area expected to be underwater during a 100-year flood.

While few argue with the programs intentions there is much disagreement over where exactly the floodplain lines should be drawn and what data and formula should be used to determine the placement of those lines. In Washington the effort has become particularly contentious in King and Skagit Counties. There is much at stake since as with the Growth Management Act and its urban growth areas many property owners will find themselves on the restricted-development side of the line with decreased property values to match.

About 60 percent of Skagit Countys commercial economic activity could be in the floodplains says Mike Woodmansee of Fisher and Sons in Burlington. Its like a ticking clock. Having property in the floodplain may not affect you for years but once you want to develop redevelop or sell the restrictions and diminished value becomes real. It creates a high potential for economic decay in an area.

In Skagit County the dispute has been over the use of data. Woodmansee and local groups argue that FEMA which relies on the USGS and Army Corps of Engineers is inappropriately using flood data from 1921 and earlier. While the survey data may be accurate the modeling computations used by the federal agencies to create estimated river volumes significantly overstate those volumes.

Because of the challenge of implementing solutions local agencies are correct to put forth a great deal of effort toward making sure the threat is accurately quantified Woodmansee says.

FEMA is at least giving some consideration to the local groups point-of-view as it has yet to release draft maps for Skagit County although they are expected within 6 months.

For King County FEMA has released a proposed floodplain that would hamper development in the states largest industrial area along the Green River including much of downtown Kent and parts of Renton and Auburns commercial districts. The draft plan would double the floodplain along the river from 2000 properties and $4 billion in assessed value to 4100 properties with $7.5 billion in value according to a Seattle Times article.

The key issue there is the existing levees. In creating the floodplain maps FEMA considers levees as non-existent if they do not meet specific requirements. King County scrambled to approve a property tax increase for a new flood-control district that will fix Green River levees and get large parts of Renton Kent and Auburn out of the expanded floodplains. But updating the levees could take years and it is unclear how the floodplain maps would be affected in the short term.

In the meantime King County has appealed the proposed maps which if finalized would mean most new construction in this industrial area would have to be raised four to 13 feet off the ground.

Pre-existing buildings in floodplains are grandfathered; no structure has to come down due to the floodplain mapping. But if an owner wants to construct a new structure or substantially improve an existing one the owner will be required to comply with federal and state flood hazard construction standards. Local governments develop the ordinances regarding development in order to participate in NFIP. These ordinances must meet State requirements and include minimum requirements including:

• New construction and substantial improvement of any structure shall have the lowest floor including basement elevated to or above the base flood elevation (BFE);

• All new construction and substantial improvements shall be anchored to prevent flotation collapse or lateral movement of the structure;

• All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.

Substantial improvement means any repair reconstruction or improvement of a structure the cost of which equals or exceeds 50 percent of the market value of the structure.

There are additional restrictions and even more for property in the floodway the section of the floodplain such a stream and adjacent areas through which the bulk of the floodwater is expected to drain out of the area. Local jurisdictions may choose to adopt more than the minimum restrictions such as larger setbacks from the floodways.

Flood hazard insurance is not mandatory for property within the floodplain but it is virtually so. Flood insurance is a prerequisite for receiving federal disaster relief after a flood and lenders may require it.

Another aspect of the floodplain mapping effort is its affect on other laws. The new maps should they expand the floodway and adjoining floodplain will expand the areas subject to the Shoreline Management Act (SMA). Also should the maps designate an area as floodplain that was previously designated as an urban growth area counties will have to re-think their plans under the Growth Management Act (GMA).

A thorough white paper on the floodplain map issue was recently completed by attorneys at the GordonDerr firm on behalf of Washington Realtors. That paper is available by clicking here. The authors state that unlike drawing urban growth area boundaries local jurisdictions have had relatively little control over FEMAs floodplain remapping efforts. Both King County and Skagit County have made significant efforts to influence the process and resulting maps with yet indeterminate results. Consequently like the property owners themselves many of the jurisdictions are also likely to find the new floodplain maps difficult to accept.

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