Microplastic concentrations in Nevada’s Truckee River increased nearly tenfold during spring runoff, according to new research that offers a glimpse into how plastic pollution moves through some western waterways. Researchers with the Desert Research Institute sampled the river, which flows from Lake Tahoe through Reno and eventually to Pyramid Lake, during low flows in fall 2022 and again during unusually high spring flows in 2023. On average, they detected 0.4 microplastic particles per liter in the fall and 3.7 per liter in the spring. … [T]he new research highlights how much concentrations can change depending on river conditions — something the authors say water managers and researchers should consider when deciding when to sample.