King County farmers would get new flood protection with task force proposals

Farmers on highly productive King County agricultural lands would get additional protection for their livestock and farm supplies while ensuring continued flood protection and preservation of ecologically valuable river habitat through proposals contained in a new report.

"The Snoqualmie Valley is a tremendously valuable natural resource that contains a great wealth of agricultural land," said King County Executive Ron Sims. "At the same time, valley farms face a significant risk from flooding. Our job is to help agriculture thrive, but not at the expense of increasing flood risk or degrading the river's ecological functions for fish and wildlife."

The Snoqualmie Flood Farm Task Force report offers several proposals, including requesting assistance in raising existing farm buildings out of floodwaters, allowing new non-residential agricultural buildings in the Federal Emergency Management Agency (FEMA) floodway and providing protection for farm equipment and supplies.

The task force, authorized by the King County Council, was composed of area farmers and King County staff that worked for three months to assess the impacts of flooding on agriculture and to identify alternative measures for reducing the flood impacts without increasing the flood risk to people and property.

The task force developed recommendations for changes to regulations and additional technical support and funding that will help the agriculture industry in the Snoqualmie Valley and throughout the county.

The task force made 16 recommendations, including creating a "compensatory flood storage bank" within the valley floodplain. King County would track fill as it is removed from the floodplain and then carefully monitor an equal amount of fill placement, such as building an elevated farm pad.

"By tracking increases in flood storage capacity that is created in the valley through fill removal, we can potentially add an equal amount of fill to create pads where farmers can place their equipment, supplies and livestock during flood events," Sims said.

The County Council authorized a pilot project in 2007 to construct elevated farm pads on fill and task force recommendations included an analysis of the 2007 pilot project to determine the impact of that project on flood storage and conveyance.

"During the pilot study, a specific amount of fill was added to create or modify 10 farm pads in different areas of the Snoqualmie Valley," Sims said. "We found no measureable change in the flood elevation across the pilot areas."

Other task force recommendations include:

1. Allowing non-residential, agricultural accessory buildings in the FEMA-defined floodway, including structures on farm pads;
2. Providing $100,000 in annual funding from the King County Flood Control Zone District to help pay for hydraulic analyses and to elevate agricultural buildings in the floodplain. Some level of property owner contribution would be required to complete the elevations.
3. Allowing farm pads to be constructed within the floodway, which is land that is close to the river and more hazardous during flooding. All FEMA floodplain standards would have to be met before construction would be allowed.
4. Completing a hydrologic study in the Snoqualmie River basin to understand any changes to flooding as a result of land-use development within the valley. Sims said the results of this study would help inform future flood reduction strategies.

"These recommendations hold a lot of promise for the future of agriculture in both the Snoqualmie and Green River valleys," he said. "They go far beyond simply addressing the need for protection from potential increases in the magnitude and frequency of flood events we expect to see due to global warming."

The report is available online at
http://dnr.metrokc.gov/wlr/lands/agriculture/farm-flood-task-force-report.htm.

The task force's eight meetings between October 2007 and January 2008 featured presentations on and discussion of potential causes of increased flooding in the Snoqualmie Valley, and on the regulations that provide flood protection and the ways they could be modified to address the needs of agriculture in the floodplain. The report includes the findings from these discussions and the resulting 16 recommendations that emerged.

Sims said the appropriate flood-related changes to county building codes will be transmitted to the County Council by April 30.