The Class A1 (primary contact recreation) uses are assessed (monitored) as "not supported" based on levels of indicator bacteria that exceed state water quality criteria.  The Class A1 use designation was added to this river segment by the state of Iowa in March 2006; this change in use classification was approved by U.S. EPA in February 2008.  The Class A1 (primary contact recreation) uses are assessed as “not supported” due to violations of Iowa’s water quality criteria for indicator bacteria.  Results of IDNR monitoring from 2012 through 2014 showed that recreation season (March-November) geometric means based on the approximately eight samples collected per year were above Iowa’s Class A1 water quality criterion of 126 orgs/100 ml:  The annual recreation season geometric means for 2012, 2013 and 2014 are as follow:  293, 271, and 1,131 E. coli orgs/100 ml., respectively.  These geometric means exceed the Class A1 criterion of 126 E. coli orgs/100 ml.  Fourteen of the 24 samples (58%) exceeded Iowa’s single sample maximum criterion of 235 E. coli orgs/100 ml.  According to U.S. EPA guidelines for Section 305(b) reporting and IDNR’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).  Results of USGS monitoring near Fulton were consistent with results of Iowa DNR monitoring:  the 2013 recreation season geometric mean was 1,811 orgs/100 ml and the 2014 geometric mean was 1,644 orgs/100 ml.  

The Class B(WW1) aquatic life uses are assessed as “fully supporting” based on results of IDNR/SHL chemical/physical monitoring at the IDNR/SHL ambient monitoring station near Hurstville.  Results of this monthly ambient water quality monitoring show no violations of Class B(WW1) water quality criteria for pH, dissolved oxygen, or ammonia-nitrogen in the approximately 36 samples analyzed for conventional pollutants during the 2012-2014 period.  These results suggest "full support" of the Class B(WW1) aquatic life uses. 

Results of USGS monitoring near Fulton also suggest full support of the Class B(WW1) aquatic life uses.  None of the approximately 40 samples collected from April 2012 to October 2014 violated Class B(WW1) criteria for ammonia, dissolved oxygen or pH. 

The Class B(WW1) aquatic life uses also remain assessed (evaluated) as “fully supporting” based on biological sampling.  This biological assessment was based on data collected in 2006, 2012, 2013 and 2014 as part of the IDNR/SHL stream sampling projects.  A series of biological metrics that reflect stream water quality and habitat integrity were calculated from the biocriteria sampling data.  The biological metrics are based on the numbers and types of benthic macroinvertebrate taxa and fish species collected in the stream sampling reach.  The biological metrics were combined to make a fish community index of biotic integrity (FIBI) and a benthic macroinvertebrate index (BMIBI).  The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum).  The 2006 FIBI score was 61 (good).  The 2012 BMIBI score was 53 (fair), the 2013 BMIBI score was 48 (fair) and the 2014 BMIBI score was 59 (good).  The aquatic life use support was assessed (evaluated) as fully supporting (=FS), based on a comparison of the FIBI and BMIBI scores with biological impairment criteria (BIC) established from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2008.  The FIBI BIC for this ecoregion is 36 and the BMIBI BIC for this ecoregion is 51.  This segment passed the FIBI BIC 1/1 times in 2006 and passed the BMIBI BIC 2/3 times in the last five years.  This assessment is considered evaluated because the drainage area (563 mi2) above the sampling site was greater than the maximum limit (500 mi2) that was used to calibrate the Iowa wadeable stream impairment criteria.  Even though this site passed both the FIBI and BMIBI BICs, it is uncertain as to whether or not this segment is meeting the aquatic life criteria because the site used for the assessment doesn't fall in the calibrated watershed size.

Monitoring data collected from the IDNR/SHL ambient fixed station near Maquoketa/Hurtsville (10490001) during the 2010-2014 data assessment period were sufficient to complete a Nutrient Impact Assessment (NIA). Data analysis methods and screening benchmark values for nutrient stressor and response parameters described in the IDNR’s 2016 NIA methodology were used to examine for nutrient impacts often associated with low biotic index scores and violations of dissolved oxygen (DO) criteria. Nutrient stressor: The median concentration of total phosphorus (TP) was 0.22 mg/L among samples collected during the June 15- October 15 index period. The TP benchmark (0.10 mg/L) was exceeded in 18 of 20 samples. The percentage exceeding (90%) was greater than (failing) the 50% threshold with high statistical confidence (> 90%). Nutrient response parameter: The median concentration of algal chlorophyll A suspended in water (WCHLA) was 11 ug/L. The WCHLA benchmark (20 ug/L) was exceeded in 2 of 20 samples. The percentage exceeding (10%) was less than (passing) the 50% threshold with high statistical confidence (> 90%). The median rating of filamentous algae coverage (FLMA) on hard substrates was 0 (absent). The FLMA benchmark (3; 50%-75%) was exceeded in 0 of 8 observations. The percentage exceeding (0%) was less than (passing) the 50% threshold with high statistical confidence (> 90%).

The results of this “evaluated” assessment indicate the presence of elevated levels of the nutrient stressor parameter (TP) and low levels of the nutrient response parameters, WCHLA and FLMA. This combination of results is interpreted as representing a moderate risk of aquatic life use impairment due to nutrient enrichment. Continuous monitoring data were not available to examine for violations of DO criteria; however, the benthic macroinvertebrate index (BMIBI) results described suggest full attainment of aquatic life uses. Based on the assessed risk level, the stream segment is considered a moderate priority for follow-up nutrient impact monitoring.

The fish consumption uses remain "not assessed" due to lack of fish contaminant monitoring in this river reach.