Clear Creek IA 03-SSK-956
mouth (S 1/2 S33 T84N R24W Story Co.) to headwaters in NW 1/4 S4 T83N R25W Boone Co.
- Cycle
- 2026
- Current Phase
- Public Comment
- Overall IR
- 3 - Insufficient data exist to determine whether any designated uses are met.
- Trend
- Stable
- Created
- 10/27/2025 3:11:49 PM
- Updated
- 1/8/2026 2:46:37 PM
The Class A1 use was assessed (evaluated) as "WINOFI” due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. All other designated uses were "not assessed."
Data Sources: Data
Source Data
Source ID Data Type Data Age Site ID Site Name Site Description Story Co. 26 WQ CY
2022-2024 99990162 Clear Creek Site monitored by
Prairie River Watershed Group and Story Co. Conservation Site ID Data
Source ID # Samples
per Year (2022/ 2023/2024) 2022
Geometric Mean 2023
Geometric Mean 2024
Geometric Mean Violates
Annual Geometric Mean? # 2022
SSM violations / SSM Violations needed for impairment # 2023
SSM violations / SSM Violations needed for impairment # 2024
SSM violations / SSM Violations needed for impairment Violates
Annual SSM Significantly >10% Rule? Assessment
Type Support
Level 99990162 26 4/7/4 1039 520 1298 YES 3 / NA 5 / 3 4 / NA YES MONITORED NOT The
bacteria samples were collected by the Prairie Rivers Watershed Group and
Story County Conservation with the analyses conducted by the City of Ames.
Since the data were not collected under a DNR-approved quality assurance
plan, the assessment was considered "evaluated" instead of
"monitored." According to Iowa DNR’s assessment/listing
methodology, impairments based on “evaluated” assessments are of lesser
confidence and are not appropriate for Section 303(d) listing (Category 5 of
the Integrated Report). The Iowa DNR does, however, consider these
assessments as appropriate for listing under Category 3b of the Integrated
Report (waters potentially impaired and in need of further investigation).
PresumptiveClass A1 - Indicator Bacteria:
Presumptive Class BWW1 - No Data