As the spring weather continues to warm, most boaters are starting the process of dusting off the boat or personal watercraft to begin a new season on the area lakes and rivers.
This is also the time when state officials in Idaho, Washington and Montana begin the inspections necessary to keep out invasive species such as zebra and quagga mussels, which can turn any fresh body of water into a new breeding ground.
Native to Russia, zebra mussels are a small mollusk with sharp shells. Many of the organisms have a striped pattern on the shell, which gave them their name.
The non-native species was released in the Great Lakes some 30 years ago from the ballast of a Russian ship, and the zebra mussels have spread throughout the Northeast, Upper Midwest and Southeast. They have also been discovered in Arizona’s lakes Mead, Powell and Havasu.
“Zebra and quagga mussels are the most invasive and destructive to the environment, as well as the economic infrastructure,” said Allen Pleus, who leads the aquatic invasive species unit for the Washington Department of Fish and Wildlife.
The mussels colonize on any underwater hard surface, including the hulls of boats and dam locks, and often push out native species of mussels. Their shells can also cut swimmers feet at beaches and from colonizing the ladder steps of boats.
“They can be particularly damaging to dams and fish ladders,” Pleus said. “They can clog them up and it could take thousands and up to millions of dollars a year to mitigate them.”
In some cases, states have been forced to install chlorine drips to keep them away. In extreme cases, officials have had to hire divers to scrape the mollusks from clogged water intakes.
As a result, several states began mandatory boat inspections to prevent their spread. The Idaho Department of Parks and Recreation opened one on Interstate 90 just east of the Idaho border in 2009 to inspect Washington boaters heading into Gem State waterways.
Last year alone, Montana inspectors searched 35,000 watercraft and found 57 fouled by zebra mussels or other invasive species.
While the number of Idaho check stations will eventually grow to 16, the only one currently open is set up near Rose Lake, which is one of the chain lakes attached to the Coeur d’Alene River system. The I-90 check station will open prior to Memorial Day, according to the Idaho Department of Parks and Recreation.
Unless the boat is filthy, inspectors typically are not targeting those people who are getting their old fishing boat out of the barn for the first time of the year.
But zebra mussels have survived as long as 30 days out of water. And their tiny young, called veligers, can survive weeks in standing water located anywhere in the boat.
In addition to animals, invasive plants can be spread in the same way. Just a chunk of a leaf from Eurasian milfoil can start a new colony if transported into a new body of water, Pleus said.
“Some of these species, we don’t know how long they can persevere out of water,” Pleus said. “If somebody didn’t clean their boat and it has a lot of gunk on it – even if it’s a year old – it’s impossible to tell how old that is.”
Officials in all three states want boaters to think “clean, dry, drain,” as in clean the hull, make sure the boat is dry and drain anything that may hold liquid.
Of particular risk are wake boats, which suck in hundreds of gallons of water as ballast. Only one wake boat trip to Arizona’s Lake Havasu could bring thousands of juvenile zebra mussels in the hull of the boat if it is not properly drained, Pleus said.
“It’s not only the (mussels) that attach that are the danger,” he said. “In that raw water that comes in could be diseases and parasites and other small creatures, like spiny water fleas. We want them to wash their boats to prevent what was in the last water from spreading.”
Boaters must stop
Motorists in Washington, Idaho and Montana are required to stop at a boat check station if they are transporting any type of water craft.
Unlike Montana and Idaho, which have several semi-permanent check stations, Washington typically sets up “pop-up stations,” Pleus said.
“They typically are around Spokane or other border locations or at boat launches, based on our risk assessment,” he said. “Our resources are limited so we have to be very strategic about how we apply them.”
The stations are well marked and set up in a place that makes it easy for motorists to pull over, he said.
If a motorist pulling a boat passes the check station, the inspectors work with law enforcement to get compliance.
“Their primary role is that if people don’t stop, they can chase them down and tell them that they need to be inspected,” Pleus said. “It’s rare that they get a ticket unless they are very noncompliant with our request.”
The Associated Press contributed to this report.
Local journalism is essential.
Give directly to The Spokesman-Review's Northwest Passages community forums series -- which helps to offset the costs of several reporter and editor positions at the newspaper -- by using the easy options below. Gifts processed in this system are not tax deductible, but are predominately used to help meet the local financial requirements needed to receive national matching-grant funds.
Subscribe to the sports newsletter
Get the day’s top sports headlines and breaking news delivered to your inbox by subscribing here.