English Creek IA 04-LDM-1057
mo to Long Branch S16T74NR20W MarionCo
- Cycle
- 2022
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 12/28/2021 9:50:47 AM
- Updated
- 12/28/2021 9:57:24 AM
The Class BWW2 use was assessed as “not supported” based on biological sampling data. 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 507 English Creek Knoxville – REMAP #160 Benthic
Macroinvertebrates: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/Thermal BM Sample Gear BMIBI score BMIBI Class 40a BMIBI BIT BMIBI Pass/ Fail 507 8/14/14 74 40a MS/WW ArtSub 24 Poor 41 Fail 507 9/11/13 74 40a MS/WW ArtSub 22 Poor 41 Fail 507 8/1/13 74 40a MS/WW ArtSub 17 Poor 41 Fail BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/Thermal Riffle Stream? FIBI score FIBI Class 40a FIBI BIT FIBI Pass/ Fail 507 8/14/14 74 40a MS/WW NA 17 Poor 33 Fail 507 9/11/13 74 40a MS/WW NA 0 Poor 33 Fail Community Assessment Type Assessment Result Support Level IR Category Reason Benthic Macroinvertebrates Evaluated Fail (0/3) Not Fish Evaluated Fail (0/2) Not Overall Evaluated Fail Not 5bv Assessment was evaluated because it included samples
not collected in the last five years. Continuous monitoring data from 2013 and 2014 were
examined for DO and stream temperature criteria violations. The lowest DO
concentration recorded in 53 days of continuous monitoring was 2.3 mg/L. The
daily DO minimum concentration failed to meet the 24-hour DO criterion (4 mg/L)
in 4 of 53 days and the 16-hour DO criterion (5 mg/L) in 2 of 53 days. The 2013
and 2014 combined percentage exceeding the 24-hour DO criterion (7.5) was
slightly less than (passing) the 10% impairment threshold used to assess
conventional water quality parameters; however, the associated statistical
analysis confidence level was not high (<90%). The 2013 and 2014 combined
percentage exceeding the 16-hour DO criterion (3.8%) was less than (passing)
the 10% impairment threshold; however, the associated statistical analysis
confidence level was not high (<90%). The maximum stream temperature recorded
during the sensor deployment period was 31.2 degrees (C). The temperature
criterion for warmwater interior streams (32 C) was exceeded in 0 of 53 days.
The percentage exceeding (0%) was less than (passing) the 10% impairment
threshold with high statistical confidence (>90%). Based on these data, the
BWW1 aquatic life use was assessed as not impaired by DO and temperature. The
DNR’s continuous monitoring assessment methodology specifies that the frequency
of violations must exceed the 10% threshold with greater than 90% statistical
confidence in order to assess the aquatic life use as impaired. The assessment
type is considered as “monitored” because the data meet the minimum
requirements of the DNR’s continuous monitoring assessment methodology. Because
of the contradictory results showing DO violations in the first year (2013) and
not the second year of monitoring (2014), additional continuous monitoring of
DO and temperature is strongly recommended.
Presumptive Class A1 - No Data
Class BWW2 - Biological Sampling:
Fish:
Overall:
Class BWW2 – Continuous Monitoring Assessment: