Iowa DNR's Twitter Iowa DNR's Flicker Iowa DNR's YouTube Iowa DNR's Pinterest Iowa DNR's Facebook | Iowa Outdoors Magazine | News | Contact Us

Site Search  search button

Iowa's Ambient Watershed Monitoring and Assessment Program

Sunset Lake Lillies


The Water Quality Monitoring and Assessment Section of the Iowa DNR is responsible for the design, implementation and management of Iowa's Ambient Water Monitoring Programs. The purpose of these programs is to provide consistent, unbiased information about the condition of Iowa's surface and groundwater resources so that decisions regarding the development, management, and protection of these resources may be improved.

What we do

Lake Monitoring

The Ambient Lake Monitoring program samples over 130 lakes in Iowa each summer. Each lake is sampled three times throughout between May and September: once in early summer, once in mid-summer, and once in late summer/early fall. Data from this project is used to assess the health of our lakes and target individual lakes for restoration and watershed improvement activities. Monitoring is currently completed through a partnership with the Iowa State University Limnology Laboratory. Monitoring results and mini-reports explaining water quality for individual lakes can be found at:

Shallow Lakes and Wetlands Monitoring

Annual monitoring at many of Iowa’s shallow lakes and wetlands documents water quality and ecosystem health of these important resources. Wetlands are essential wildlife habitats and act as natural filters, trapping excess nutrients and sediment traveling downstream. DNR wetland monitoring is sponsored by a partnership between 3 bureaus within the DNR and several non-profit organizations, such as Ducks Unlimited and Pheasants Forever.

Shallow Lake monitoring is targeted to show changes in water quality after restoration activities. Monitoring has shown dramatic increases in water clarity after restoration. Future monitoring activities will continue to document water quality and target waterbodies for future work.

Beach Monitoring

The Iowa DNR beach monitoring program samples numerous state park and city/county beaches each week throughout the summer for indicator bacteria and algal toxins.  Beach monitoring is targeted at providing up to date information for recreating at our many beaches. Weekly monitoring results are posted at:

Stream Monitoring

Monthly ambient stream monitoring in a fixed network of sites across the state have been sampled for a variety of parameters.  These data are processed into informational products for the public and resource managers, which can be used to develop strategies to protect and improve water quality in Iowa. More information and monitoring results can be found at:

Biological Monitoring

Since 1994, the Iowa Department of Natural Resources and the State Hygienic Laboratory (SHL) have sampled fish and benthic macroinvertebrates across the state to assess the biological integrity of Iowa's streams and rivers. Benthic macroinvertebrates are small animals, such as aquatic insects, crustaceans, leeches, and snails that live on the stream bottom. The numbers and types of aquatic organisms found in a stream are useful indicators of the stream's health because they reflect changes in water quality and habitat.

All data collected as part of the biological assessment program can be found in the online BioNet database.

Water Quality Assessments

Ambient water quality monitoring data and biological assessments are an important part of the 305(b) Water Quality Reporting process, as they provide quantitative data to assess the quality of Iowa's water resources.

These assessments are prepared under guidance provided by the US EPA under Section 305b of the Clean Water Act to estimate the extent to which Iowa's waterbodies meet the goals of the Clean Water Act and attain State water quality standards, and share this information with planners, citizens and other partners in basin planning and watershed management activities.