Changing Planet

Searching for Micro-Trash in a Wild Western River

Nearly 60 outdoor enthusiasts from southwest Montana come together four times a year to study, enjoy, and protect the Gallatin River as it washes the mountains down to the Missouri.

These volunteers visit assigned locations within the Gallatin watershed, collecting water samples to be analyzed for presence and quantity of microplastics—minuscule pieces that scratch, flake, fall, or otherwise wear off any number of plastic-containing products we use every day.

Photographer Louise Johns joined two groups of volunteers recently as they headed out to their assigned sampling sites in the middle of winter. Her images give you a sense of what it means to be a volunteer for the ASC Gallatin Microplastics Initiative.

Volunteers Kirra Paulus and Gerrit Egnew use kayaks to access their sample site in the Gallatin River. Photo byLouise Johns


Volunteer Claire Hood chops through the surface ice to access the river below. Photo by Louise Johns


Gerrit transports 1-liter Klean Kanteen sample bottles to the site. Photo by Louise Johns


Claire snowshoes to access her group’s sampling site. Photo by Louise Johns


Gerrit rinses the bottle prior to sampling to decrease the risk of contamination. Photo by Louise Johns

See the full slideshow here.

Note: Even though participants may wear synthetic clothing to stay safe in the winter weather or sample from plastic kayaks, ASC takes specific precautions to limit sample contamination including documenting what is worn in the field and filling bottles on the upstream side of the collector. For more detailed information please read the Microplastics FAQs.

Learn more about our work with Microplastics on our website, the Field Notes blog, and by following us on FacebookTwitterInstagram, and Google+. Find more work by Lousie Johns on her website.

Gregg Treinish founded Adventure Scientists in 2011 with a strong passion for both scientific discovery and exploration. National Geographic named Gregg Adventurer of the Year in 2008 when he and a friend completed a 7,800-mile trek along the spine of the Andes Mountain Range. He was included on the Christian Science Monitor's 30 under 30 list in 2012, and the following year became a National Geographic Emerging Explorer for his work with Adventure Scientists. In 2013, he was named a Backpacker Magazine "hero", in 2015, a Draper Richards Kaplan Entrepreneur and one of Men's Journal's "50 Most Adventurous Men." In 2017, he was named an Ashoka Fellow. Gregg holds a biology degree from Montana State University and a sociology degree from CU-Boulder. He thru-hiked the Appalachian Trail in 2004.

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