Northbound drivers hauling watercraft past a key entry point into Washington state this Friday will be required to stop so their boats can be checked for aquatic invasive species.

Mandatory checks will take place between 9 a.m. and 3 p.m. Sept. 25 near the Ridgefield weigh station on Interstate 5, not far from the Washington-Oregon border.

The inspections are the latest in a series of more than two dozen check stations set up this year by the Washington Department of Fish and Wildlife (WDFW) in an effort to keep aquatic invasive species, primarily zebra and quagga mussels, out of state waters.

Sgt. Eric Anderson, WDFW enforcement coordinator for the program, said signs will be posted notifying motorists of the inspection at the weigh station at Milepost 18, a key entry point for out-of-state boaters.

The inspections can usually be completed in 10 minutes, Anderson said. But failure to stop for an inspection can result in a citation.

“We need the cooperation of boat owners to keep aquatic invasive species out of Washington waters,” said Allen Pleus, unit lead for WDFW’s Aquatic Invasive Species Prevention and Enforcement program.

“Once species like zebra and quagga mussels become established, they can be extremely destructive to native fish and wildlife while also causing millions of dollars in damage to public water systems.”

Invasive mussels, which attach themselves to boats or other water-based equipment, have spread quickly in recent years, Pleus said. Since the 1980s, when zebra and quagga mussels entered the Great Lakes in ship ballast water, they have shown up in more than 20 states, including California, Nevada, Arizona and Utah.

Neither species has yet been found in Washington waters, although WDFW has intercepted and decontaminated 17 boats infested with the tiny mussels in the past three years, Anderson said.

Like quagga mussels, zebra mussels are a freshwater species alien to North America that reproduces in mass quantities—one mussel can produce a million eggs in a single spawning cycle.

Importation of aquatic invasive species is a gross misdemeanor punishable by up to $5,000 in fines and up to a year in jail. Knowingly bringing such species into Washington is a felony and can result in even greater fines and jail time.

 The emphasis of the check station inspection program is to intercept invasive species, not penalize boat owners, Anderson said.

“Our primary goal is stop these species from entering our state,” he said. “At the same time, we need boat owners to recognize the importance of inspecting and cleaning their vessels before moving them from one body of water to another.”

Because invasive mussels multiply quickly, they can threaten native fish and wildlife by consuming available food and smothering some species, Pleus said. They can also clog water intake systems at power plants, irrigation districts, public water suppliers and other facilities, causing millions of dollars in damage.

Pleus noted that mandatory check stations are just one way WDFW is working to keep invasive species out of Washington’s waters. The department, he said, also works closely with the Washington State Patrol, the U.S. Coast Guard and public agencies in Oregon and Idaho to detect and eradicate the tiny invaders on both recreational and commercial vessels. 

More information on aquatic invasive species is available on WDFW’s website.