Funds added to King County budget for flood protection
October 12, 2009 · Updated 4:11 PM
The King County Flood Control District Board of Supervisors revised the 2009 capital budget and six-year capital improvement plan to provide additional money for emergency flood protection efforts in the Green River Valley.
The Green River Valley is at risk of serious flooding as a result of reduced storage capacity due to concerns about the compromised right abutment of the dam. During heavy rain events, the Corps may be forced to release substantially more water into the Green River, which would result in higher peak flows of longer duration that could exceed the capacity of the levee system.
The Flood District’s action re-allocates approximately $8.4 million for temporary infrastructure to increase the height of the Green River levees to accommodate higher flows. The funding will also make certain that measures have been taken to ensure maximum operational capacity of the Black River Pump Station. The pump station provides critical pumping capacity to drain the lower Green River Valley during a flood.
Green River flooding would affect the entire region as the area is home to tens of thousands of residents, major employers and the region’s largest warehouse and distribution operations. The Burlington Northern Santa Fe Railway’s mainline also runs through the valley, connecting commerce in the Northwest to the rest of the country. A significant amount in economic output would be lost for each day that a flood event shut down those industrial areas.
King County agencies are actively pursuing reimbursement from the federal government for costs associated with the Howard Hanson Dam situation.
Highlights about the uses for funding include:
• Alternatives for temporarily increasing levee protection under consideration include super size sandbags called super sacks that are moved utilizing a forklift, and container units that are sandbags structurally reinforced using collapsible wire mesh.
• Plans to ensure the Black River pump station stays fully operational during a flood event include constructing a temporary embankment around the pump house to keep out floodwaters, possibly utilizing additional pumps to augment the existing capacity at the pump station, and purchasing or renting a backup generator to ensure full electrical power to the pump station’s equipment.
Information about the King County Flood Control District can be found at www.kingcountyfloodcontrol.org.