Assessment Process
Lakes and segments of streams and rivers in Iowa each have specific designated uses based on how they are used—recreation, such as swimming or boating; drinking water; fish consumption; or maintaining a healthy population of fish and other aquatic life. Every two years, Iowa must report on its progress in meeting water quality goals to the U.S. Environmental Protection Agency. The state prepares a report, called the 305(b)/303(d) Integrated Report, that shows how well Iowa waters are meeting those goals. The report includes waters that meet the designated uses, waters in which we need more information and waters that are impaired.
Preparation of Iowa’s 305(b)/303(d) Integrated Report includes the following basic steps:
- Assemble all existing and readily available water quality-related data collected in and around Iowa during the assessment period;
- Identify water quality-related data and information of sufficient quality and quantity for purposes of developing scientifically defensible water quality assessments;
- Compare these water quality-related data and information to state water quality standards to determine the degree to which assessed segments meet these standards;
- Identify Section 303(d) impairments that are based on water quality-related data and information that meet the state’s requirements for data quantity and data quality;
- Place all segments into one of the five categories specified in U.S. EPA’s Integrated Report guidance (2003, 2005) for water quality assessment and listing;
- Prepare the state list of segments in need of further investigation as required by state law;
- Prioritize the waterbody segments on the draft Section 303(d) list (Category 5) for TMDL development;
- Provide the draft Integrated Report, including the draft Section 303(d) list (Category 5), to the public for review and comment;
- Revise and finalize the integrated report based on new information and public input;
- Submit the final Integrated Report, including the Section 303(d) list, to U.S. EPA for approval/disapproval;
- Develop a schedule for development of TMDLs for Section 303(d)-listed (IR Category 5) waterbody segments.
Current and previous Integrated Report methodology documents can be found on the Publications page.