Buck Creek IA 01-MAQ-45
mouth (S11 T87N R4W Delaware Co.) to Golden Branch in S11 T87N R5W Delaware Co.
- Cycle
- 2026
- Current Phase
- Public Comment
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Improving
- Created
- 10/27/2025 3:08:57 PM
- Updated
- 12/30/2025 12:30:51 PM
The Class BWW2 use was assessed as "not supported" based on information from the report "Statewide Assessment of Freshwater Mussels (Bivalva, Unionidae) in Iowa Streams" by Arbuckle et al. (2000). All other designated uses were "not assessed."
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description Iowa DNR 6 BIO See Below 1029 Buck Creek BK001 – 3.5 miles west of Hopkinton Iowa DNR 6 BIO See Below 1030 Buck Creek BK002 – 3 miles west of Hopkinton BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 47c BMIBI BIT BMIBI Pass/ Fail 1030 8/21/24 27.6 47c MS Hess 70 Good 70 Pass BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage Riffle Stream? FIBI score FIBI Class 47c FIBI BIT FIBI Pass/Fail 1029 8/15/22 45 47c MS Undetermined 65 Good 44 Pass 1030 8/4/22 46 47c MS Undetermined 65 Good 44 Pass 1029 8/3/21 45 47c MS Undetermined 62 Good 44 Pass 1030 8/2/21 46 47c MS Undetermined 59 Good 44 Pass 1029 7/30/20 45 47c MS Undetermined 58 Good 44 Pass 1030 7/28/20 46 47c MS Undetermined 63 Good 44 Pass Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (1/1) Full Assessment was
evaluated because it was based on a single 2024 Fish Monitored Pass (6/6) Full BMIBI sample. Impairment
remains until two passing BMIBI samples are Overall Evaluated Fail Not 5bt collected in a recent five-year
period. Freshwater Mussel Survey # Freshwater Mussel Species # Freshwater Mussel Species Increase/Decrease % Freshwater Mussel Species Increase/Decrease Assessment Type Support Level IR Category 1984-85 (Frest 1987) 6 1998-99 (Arbuckle et
al. 2000) 1 -5 -83% Evaluated Not 5b As presented by
Arbuckle et al. (2000), the potential causes of declines in species richness
of Iowa's freshwater mussels include siltation, destabilization of stream
substrate, stream flow instability, and high instream levels of nutrients
(phosphorus and nitrogen). Their study also suggested the importance of
stream shading provided by riparian vegetation to mussel species richness.
Presumptive Class A1 – No Data
Class BWW2 - Biological Sampling:
Benthic Macroinvertebrates:
Fish:
Overall Assessment:
Class BWW2 – Freshwater Mussel Sampling: