All Runoff Science group runs are detailed below. These runs will pair citizen science observations and sampling of water bodies with an epic adventure. Each set of observations is designed to be completed in less than 5 minutes, allowing enough time for the group to refuel and regroup before continuing on the trail. These runs are for any outdoor-loving trail runners who might want to learn more about their natural environment and ways they can protect it.
Cronan Ranch
When: September 20, 2026 at 8:00 am
Where: Pilot Hill, CA
This run is designed for runners of any level, who are curious about participating in a Runoff Science adventure but are looking to “get their feet wet” before diving into something bigger. We’ll run a 4.4 mile loop from the parking lot at Cronan Ranch. Along the way, we’ll collect surface water samples and visual observations at the South Fork of the American River.
Loch Leven
When: October 17, 2026 at 8:30 am
Where: Big Bend, CA
We’ll run a 7.4 mile out-and-back from the Loch Leven Trailhead parking lot to High Loch Leven Lake. Along the way, we’ll collect surface water samples and visual observations at Loch Leven Lakes and Little Granite Creek. These water bodies feed the North Fork of the American River, which we will sample in the more downstream reaches during our Stevens Trail run on November 1.
Stevens Trail
When: November 1, 2026 at 8:00 am
Where: Colfax, CA
We’ll run a 7.5 mile out-and-back from the Stevens Trailhead parking lot to the North Fork of the American River. Along the way, we’ll collect surface water samples and visual observations at the North Fork of the American River and the following tributaries: Robbers Ravine and Secret Ravine.
Lake Spaulding & Fordyce Creek
When: November 21, 2026 at 8:00 am
Where: Emigrant Gap, CA
We’ll run a 14.7 mile out-and-back from the Emerald Pools Trailhead Parking to Fordyce Creek. Along the way, we’ll collect surface water samples and visual observations at Jordan Creek, Fordyce Creek, and the South Yuba River. We’ll also sample the South Yuba in the more downstream reaches during our South Yuba run on December 5.
South Yuba
When: December 5, 2026 at 8:00 am
Where: Washington, CA
This run is designed for runners of any level, who are curious about participating in a Runoff Science adventure but are looking to “get their feet wet” before diving into something bigger. We’ll run a 4.5 mile out-and-back from the South Yuba Trailhead at Poorman Creek. Along the way, we’ll collect samples and visual observations at the South Yuba River and the following tributaries: McKilligan Creek, Poorman Creek, and any ephemeral streams.
Thank you to Zaubercactus for the incredible flyer for our Fall Sampling Runs! Check out more of their work on their website and Instagram.