This dataset describes site location information for samples collected within the western National Parks, USA, (Arches National Park (NP), Bryce Canyon NP, Canyonlands NP, Capitol Reef NP, Dinosaur National Monument (NM), Hovenweep NM, Timpanogos Cave NM, and Zion NP) for water chemistry analyses. Water-quality and bed-sediment samples were analyzed for contaminants of emerging concern at the National Water Quality Laboratory, Denver, Colorado, and Region 8 U.S. Environmental Protection Agency laboratory in Golden, Colorado. Additionally, quality assurance and quality control results are summarized.