Portage County, Wisconsin
CW11
1398600
0.00 - 16.01
16.01
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
Mill Creek was added to the Impaired Waters List for phosphorus and low dissolved oxygen in the 1998 assessment cycle. This segment was evaluated every two-year cycle from 2012 to 2024; high phosphorus levels were confirmed. This stream is part of the Wisconsin TMDL, approved in 2019.Pollutant
Total Phosphorus
Listed For
Fish and Aquatic Life
Impairments
Low DO
Current Use
Unsupported Aquatic Life
Listing Status
TMDL Approved
Attainable Use
WWSF - Warmwater Sport Fishery
Priority
Not Applicable
Designated Use
WWSF - Warmwater Sport Fishery
303(d) ID
286
Listing Date
4/1/1998
Impaired Water Notes
Synoptic surveys completed in the winter of 2000 documented dissolved oxygen concentrations below 5 mg/l at several sites in the WWSF reach. Dissolved oxygen concentrations did not fall below 5 mg/l at CTH P, the furthest downstream road crossing.
Continuous dissolved oxygen monitoring conducted in the winter of 2001 documented dissolved oxygen concentrations below 5 mg/l at sites in the WWSF reach.
Date
3/20/2002
Impaired Water Notes
This water was assessed during the 2014 listing cycle; total phosphorus sample data overwhelmingly exceed 2014 WisCALM listing thresholds for the Fish and Aquatic Life use, however, no biological data (i.e. no macroinvertebrate or fish Index of Biotic Integrity (IBI) scores) were available to assess biological impairment).
Date
2/26/2014
Impaired Water Notes
This water was assessed during the 2016 listing cycle; total phosphorus sample data overwhelmingly exceed 2016 WisCALM listing thresholds for the Fish and Aquatic Life use, however, available biological data do not indicate impairment (i.e. no macroinvertebrate or fish Index of Biotic Integrity (IBI) scored in the "poor" condition category).
Date
9/23/2015
Impaired Water Notes
This water is part of the 2019 approved Wisconsin River TMDL addressing Total Phosphorus and Total Suspended Solids.
Date
6/6/2019
Impaired Water Notes
This water was assessed during the 2022 listing cycle; total phosphorus sample data overwhelmingly exceed 2022 WisCALM listing thresholds for the Fish and Aquatic Life use.
Date
5/24/2021