By Hayley Williamson

Tahoe’s boat inspectors delivered some excellent news this month. This boating season, we experienced one of the lowest years on record of boats detected with dangerous quagga and zebra mussels—this following several years of troubling increases. Even better news is that since mandatory watercraft inspections began in 2008, there have been no new aquatic invasive species (AIS) detected in Lake Tahoe. Additionally, nearly 60 percent of boats and trailers arriving to the inspection stations are Clean, Drained, and Dry, which shows that boaters are increasingly aware of the program mantra and the most important way to prevent AIS from being transported.

Program managers with the Tahoe Regional Planning Agency (TRPA) and the Tahoe Resource Conservation District credit an additional focus on boater education and strengthened partnerships with other states as among the reasons for the positive report.

The threat to Lake Tahoe from aquatic invasive species is ever-present and, for nearly 15 years, our region has benefited greatly from one of the most comprehensive watercraft inspection programs in the nation.

Growing up in Wisconsin, I understand the broad impacts invasive species can have on ecosystems and economies. Wisconsin’s over 15,000 lakes shape the state’s landscape and outdoor culture.  The health of these lakes contributes significantly to the state’s recreation and tourist economy. However, over time, nearly 200 aquatic invasive species have been introduced into Wisconsin’s waters. These non-native species proliferate and disrupt the natural ecosystem, causing negative impacts to recreation, property values, native species, and water infrastructure. While many Wisconsin lakes are still free from AIS, the state is in a battle to stop the spread. Resource managers there and across the nation are looking to watercraft inspection programs like Tahoe’s to serve as a model for new prevention efforts.

Managing the Risk

The Lake Tahoe Watercraft Inspection Program substantially reduces the risk of AIS through boater education, mandatory inspections and decontamination services, and early detection and monitoring programs. The program protects Lake Tahoe, Fallen Leaf Lake, and Echo Lake from new introductions of invasives.

However, during the pandemic, a trend played out here and nationally that started increasing the risk and the number of AIS interceptions at Tahoe. A manufacturing shortage of new vessels coupled with increased interest in boating brought boats to Tahoe from distant waters. Many of these vessels belonged to newer boaters with less knowledge of the importance of arriving Clean, Drained, and Dry.

As a result, inspectors intercepted a record 28 boats with mussels in 2021, and 20 the year prior.

Improvements to the Program

To reverse the trend, staff went to work well ahead of the boating season to better educate boaters about the risk of aquatic invasive species before they arrive at Lake Tahoe. This was done by promoting the new watercraft inspection appointment system, advertising Tahoe’s program in national magazines, and strengthening partnerships with other programs throughout the West. The agencies joined a new, nationwide “Call Before You Haul” hotline that puts boat transporters in contact with watercraft inspectors wherever they are headed.

Even with steep gas prices this summer, boating activity remained strong. Our collective actions helped reduce the number of mussel-fouled boats intercepted to seven—one of the lowest years on record.

These are the kind of actions that continue to make Lake Tahoe’s boat inspection program a model for others. Managers are constantly looking for ways to improve customer service and efficiency while maintaining high standards based on sound science. And more improvements are coming. Funding from the State of Nevada and the Federal Bipartisan Infrastructure Law are supporting the program’s first permanent inspection station to be located on Spooner Summit.

Our inspectors can’t do it alone. It takes all of us knowing how to stop the spread of invasives to protect our waters, our recreation resources, and our regional economy. I encourage you to join us in the work to stop the spread of aquatic invasive species in the Tahoe Region and elsewhere. Find out more at

— Hayley Williamson is Vice Chair and Nevada At-Large Member of the Tahoe Regional Planning Agency Governing Board.