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Sierra Mac River Trips: Pioneers on the Wild and Scenic Tuolumne River

Chamber members since 1979, Sierra Mac’s Marty McDonnell served on the Yosemite | Hwy 120 Chamber board in 1982 when it voted to support Wild and Scenic status for the Tuolumne River, leading the way for Federal legislation to protect the Tuolumne River from the threat of three dams proposed by San Francisco, Modesto, and Turlock.

“This stretch of river now has the reputation of having the best rapids in the country for rafting and kayaking,” said Marty “Mac.” According to Marty, the Tuolumne River, or the “T” as it’s known in the trade, has an especially unique run of rapids through the wilderness that sets it apart from other runs that have extended stretches of flat water. Two side canyons (Clavey and the North Fork of the T) have great natural swimming holes, and are fun for exploring.

In the 1960’s, Marty’s father led family trips that included kayaking and rafting. His older sister, Candy, became one of the first female whitewater kayakers in the world. She passed on this passion to Marty, who started building fiberglass kayaks, renting and selling them to the fine people of the San Francisco Bay Area in the mid 60’s.

Through his sister, Marty became known to Bryce Whitmore, who ran trips on the Stanislaus, the birthplace of commercial rafting in the West. Bryce’s company “Wilderness Water Ways” began exploring the Tuolumne in the late sixties as an option to expand. Marty worked with others to pioneer and sort out the run in 1969 and in 1970, he led the first commercial trip on the Tuolumne.

Marty subsequently took over Wilderness Water Ways and after exploring all over the state, decided to focus on the Stanislaus and Tuolumne Rivers. Following a controversial and political attempt to save the Stanislaus, the Tuolumne became the main focus for what is now Sierra Mac River Trips.

Marty on the "T" 1977.

True pioneers of the sport, no rafts had run the Upper Tuolumne (also known as Cherry Creek) until Marty and three others navigated it in 1973. They had so much fun, they did it the next day as well. Until that point, Cherry Creek was considered unrunnable. But with a craft Marty designed now known as the cataraft, they were able to run the granite gorge of the Cherry Creek/Upper Tuolumne, rated as a Class V rapid. (The International Scale of River Difficulty is the most widely used whitewater grading system. In this system, whitewater–either an individual rapid, or the entire river–is classed in six categories from Class I (the easiest and safest) to Class VI (the most difficult and most dangerous).

“Families should plan to raft on the Main Tuolumne from mid-June through the rest of the season,” Marty advises. “For the Merced River, families should go whenever there is water, avoiding Spring if the water is high. We’re always happy to answer questions about the conditions.”

The 18-mile stretch on the Main Tuolumne makes for great single or multiple-day adventures. Sierra Mac offers one, two, and three-day trips with options like the 9-mile Cherry Creek section for some extra adventure. They also offer a Gourmet food and wine trip called the “California Roll,” another pioneering effort heralded as the first of its kind in the whitewater industry in 1984. Sierra Mac also offers charter trips for everything from bachelor parties to family reunions. If you fancy a wet-and-wacky wedding, Sierra Mac will run you down the Wild and Scenic Tuolumne. You bring the organ. And, anyone with a fishing license is invited to bring their gear along on Sierra Mac trips.

The river runs in the blood of the McDonnell family. Getting people on a raft to experience this beautiful natural playground is what gets Marty, his son Tom and daughter-in-law Liza (pronounced Leeza) out of their bedrolls every morning. “Living in Groveland is a blessing,” says Marty. “There is so much right here that we love…Hiking, Biking, Rafting, Yosemite. We also like working hard in the summer to have extended free time in the ‘off’ season.”

In addition to eventually taking over the rafting business, Tom and Liza recently became the new lodge owners and operators of Lillaskog Lodge, continuing the vision of original owner Bill Charlson, who recently passed. Lillaskog is currently acting as a wedding venue, vacation rental and off-site retreat space. Located across the street from Sierra Mac, Lillaskog Lodge is a natural extension to Sierra Mac’s business portfolio. Ask them about combining whitewater rafting with a stay at Lillaskog.

Sierra Mac’s base camp overlooks the Tuolumne River Canyon with stunning views, beautiful restrooms, hot showers, and plenty of parking. They now also offer a camping option at their home base.You can find out more on Canyon Ridge Camp on Hipcamp.

Over the course of a half century, Marty McDonnell has built a thriving business for himself and his family, but more importantly, his history of advocating for the environment through their connection to the Tuolumne River Trust and his lobbying efforts have protected this valuable natural resource for the benefit of our community and our visitors. His pioneering work and dedication to the Wild and Scenic Tuolumne River has helped increase the appeal of the greater Groveland area as a destination for nature lovers and fun seekers.

Marty plans to continue his dedication to preserving our Wild and Scenic rivers for the enjoyment of all, and he credits the shared vision of the business community for making it possible. “I will be forever grateful for the insight this chamber (of commerce) had to protect a treasure for our local tourism industry and for generations of whitewater boaters to come.”

So are we, Marty. So are we.

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