Little Turkey River IA 01-TRK-163
from south line of S11 T90N R3W (Delaware Co.) to confluence with unnamed tributary in the S 1/2 of S15 T90N R3W Delaware Co.
- Cycle
- 2018
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 7/31/2019 1:20:05 PM
- Updated
- 7/31/2019 1:20:16 PM
The presumptive Class A1 (primary contact recreation) uses remain assessed (monitored) (IR 5p) as “not supported” due to violations of Iowa water quality criteria for indicator bacteria. The Class B(WW2) aquatic life uses remain assessed (monitored) as “fully supported” (IR 2a). The source of data for this assessment remains the results of monitoring from March to July 2010 at IDNR TMDL station LTR2 near Colesburg, IA (STORET station 11280003). The Iowa STORET database suggests that monitoring has not been conducted at station 11280003 since July 2010.
The presumptive Class A1 (primary contact recreation) uses remain assessed (monitored) as "not supported" based on levels of indicator bacteria that exceeded state water quality criteria. The geometric mean of indicator bacteria (E. coli) in the eight samples collected during the recreational season of 2010 at Site LTR2 (914 orgs/100 ml) exceeded the Iowa water quality criterion to protect primary contact recreation uses (126 orgs/100 ml). Seven of the eight samples (88%) exceeded Iowa’s single-sample maximum criterion of 235 orgs/100 ml. According to U.S. EPA guidelines for Section 305(b) reporting and DNR’s assessment/listing methodology, if the geometric mean is greater than 126 orgs/100 ml., the primary contact recreation uses are "not supported" (see pgs 3-33 to 3-35 of U.S. EPA 1997b).
The Class B(WW2) aquatic life uses remain assessed (monitored) as “fully supported”. No violations of Class B(WW2) water quality criteria for ammonia, dissolved oxygen, pH, or chloride occurred in the nine samples analyzed from March to July 2010.