Profound changes in hydrology are occurring in Arctic and sub-Arctic regions.Ìý The Yukon River Watershed, covering 330,000 square miles in Alaska and western Canada, is no exception.Ìý Since 2006 the U.S. Geological Survey (USGS) and the Yukon River Inter-Tribal Watershed Council (YRITWC) have collaboratively managed the Indigenous Observation Network (ION) a community-based monitoring program.Ìý Tribal and First Nation environmental professionals residing in Indigenous communities across the 2,300 mile stretch of the Yukon River collect surface water samples as part of this program.Ìý Surface water samples are then analyzed at the USGS Water Resources Mission Area’s Project Laboratory in Boulder, CO.Ìý Among the many benefits of this program, participation has allowed USGS scientists to form lasting partnerships with Tribal and First Nation environmental professionals and communities that would otherwise have not been possible.Ìý These relationships have led to projects that operate in a co-production framework to incorporate Indigenous Knowledge and Observations into our understanding of changing hydrology in this region and the impacts those changes have on communities.Ìý This presentation focuses water quality results derived from the combination of ION with historic USGS. Results indicate changing surface water/groundwater flowpaths in the Yukon River watershed with results achieved from.Ìý These biogeochemical results will be presented in the context of local knowledge and firsthand observations of changing hydrology as documented in workshops focused on understanding landscape change conducted in 2017 in the Alaska Native Village of Chevak.