The Iowa Department of Natural Resources (DNR) maintains a network of sites to monitor ambient water quality in the state. The sites in this statewide ambient stream network have been monitored since October 1999 for a variety of parameters. The total number of stations monitored each year has varied. The highest number of sites monitored was 84 stream sites and 1 spring site from 2003 to 2006. DNR currently monitors
60 sites in the ambient stream network on a monthly basis.
Water quality data collected from the ambient stream network is available in AQuIA - Iowa DNR's online water quality monitoring results database. The water quality data is used to determine status and trends, determine if Iowa's rivers support beneficial uses for which they are designated, calculate nutrient loads, and support the development of new or revised water quality standards. The water quality data from the 60 monthly sites are summarized in AQuIA on a moving 10 year period (e.g., 2013-2022, 2014-2023, etc.).
Previous annual and cumulative stream summaries are available at http://publications.iowa.gov/. Enter “Stream water quality” in the Search option to retrieve these summaries.