Iowa DNR

Water Quality Assessments

Impaired Waters List

2000 305(b) Legacy Assessment Summary

Assessments for cycles prior to 2004 were conducted using a different methodology than those conducted for later cycle. This methodology differed significantly from more recent assessment procedures, and do not contain the same detailed information newer assessments have. Additionally, these assessments were conducted before the introduction of the "integrated report”, which combined both the Section 305(b) report and Section 303(d) list. Therefore, these assessments do not use the familiar "Overall Assessment Category" designations.

Due to the changes that have occurred over the years, a more limited summarization is provided for these assessment cycles.

Additional information for the 2000 assessment cycle

The 2000 assessment cycle was unique in that although the US EPA rules at the time required submittal of 303(d) lists every two years, states were not required to submit a 2000 list due to uncertainty over proposed EPA 303(d) rules. The rule changes were later withdrawn.

Iowa conducted its own 305(b) and 303(d) lists, but the official EPA record does not summary information for the 2000 cycle. The summary information presented here is for informational purposes only.

Assessment Results

The number of assessments the Iowa DNR can make in a given cycle are limited by budgets and staffing resources. The following charts show the proportions to which each waterbody type meets WQ standards, and the percentage that has been assessed in this cycle.

Rivers and Streams
Lakes and Reservoirs