Assessment Summary
The Class A1 use was assessed as "fully supported" based on the results of routine monitoring for indicator bacteria (E. coli). The Class BWW1 use was assessed as "fully supported" based on water quality monitoring data. The Class HH use was assessed as "fully supported" based on fish tissue sampling data.
Assessment Explanation
Data Sources:
|
Data
Source
|
Data
Source ID
|
Data
Type
|
Data
Age
|
Site
ID
|
Site Name
|
Site
Description
|
|
USACE
|
12
|
WQ
|
CY
2018-2020
|
17630001
|
Des Moines
River at Howell Station Landing
|
|
|
USACE
|
12
|
FT
|
See
Below
|
17630001
|
Des Moines
River at Howell Station Landing
|
|
Class A1 - Indicator
Bacteria:
|
Site
ID
|
Data
Source ID
|
#
Samples per Year (2018/ 2019/2020)
|
2018
Geometric Mean
|
2019
Geometric Mean
|
2020
Geometric Mean
|
Violates
Annual Geometric Mean?
|
# 2018
SSM violations / SSM Violations needed for impairment
|
# 2019
SSM violations / SSM Violations needed for impairment
|
# 2020
SSM violations / SSM Violations needed for impairment
|
Violates
Annual SSM Significantly >10% Rule?
|
Assessment
Type
|
Support
Level
|
|
17630001
|
12
|
10/10/10
|
11
|
8
|
14
|
NO
|
0 / 3
|
0 / 3
|
0 / 3
|
NO
|
Monitored
|
Full
|
Class A1 – pH:
|
Site
ID
|
Data
Source ID
|
#
Samples / # Years
|
Minimum
Value
|
Maximum
Value
|
Mean
Value
|
#
Violations
|
Violations
needed for impairment
|
Violates
Significantly >10% Rule?
|
Assessment
Type
|
Support
Level
|
|
17630001
|
12
|
60 / 3
|
6.79
|
8.98
|
8.02
|
0
|
10
|
NO
|
Monitored
|
Full
|
Class BWW1 -
Conventional Parameters:
|
Site
ID
|
Data
Source ID
|
Parameter
Name
|
#
Samples / # Years
|
Minimum
Value
|
Maximum
Value
|
Mean
Value
|
#
Violations
|
#
Acute / Chronic Violations
|
Violations
needed for impairment
|
Violates
Significantly >10% Rule?
|
Assessment
Type
|
Support
Level
|
|
17630001
|
12
|
Ammonia
|
60 / 3
|
0.02
|
1.02
|
0.18
|
NA
|
0 / 1
|
10
|
NO
|
Monitored
|
Full
|
|
17630001
|
12
|
Dissolved
Oxygen
|
60 / 3
|
6.64
|
19.62
|
11.1
|
0
|
NA /
NA
|
10
|
NO
|
Monitored
|
Full
|
|
17630001
|
12
|
pH
|
60 / 3
|
6.79
|
8.98
|
8.02
|
0
|
NA /
NA
|
10
|
NO
|
Monitored
|
Full
|
|
17630001
|
12
|
Temperature
|
60 / 3
|
0.6
|
28.6
|
15.1
|
0
|
NA /
NA
|
10
|
NO
|
Monitored
|
Full
|
Class BWW1 - Toxic
Parameters:
|
Site
ID
|
Data
Source ID
|
Parameter
Name
|
#
Samples / # Years
|
Maximum
Value
|
Mean
Value
|
Median
Value
|
#
Acute / Chronic Violations
|
>1
Acute / Chronic Violation
|
Assessment
Type
|
Support
Level
|
|
17630001
|
12
|
Lead
|
5 / 3
|
0.4
|
0.1
|
0.05
|
0 / 0
|
NO
|
Evaluated
|
Full
|
Class HH - Fish Tissue Sampling: 2012-2014 at
site 17630001
Fish contaminant monitoring showed low levels of
contaminants (dieldrin, heptachlor epoxide, chlordane, alachlor, and
trifuluralin) in composite samples of whole fish common carp. Levels of PCBs in
composite whole-fish carp samples for all Aroclors analyzed in from 2012 to
2014 (1016, 1221, 1232, 1242, 1248, 1254, and 1260) were all below levels of
detection. Detection levels for PCB were high in all three years; thus, data
for PCBs are inconclusive. The history of low levels of PCBs in fish from this
river segment, however, suggest that PCB levels are below the one meal per week
advisory trigger of 0.20 ppm for total PCBs (sum of Aroclors 1248, 1254, and
1260).
Composite samples of
fillets from a predator species were analyzed for mercury in all three years.
In 2012, the composite sample of largemouth bass fillets had low levels of
mercury (0.14 mg/kg). The average levels of mercury in the composite sample of
smallmouth bass fillets in 2013 was 0.10 ppm. Results were not reported for
levels of mercury in the 2014 composite sample of predator fish. Levels of
mercury in the samples from this river segment from 2012 and 2013 were below
the one meal per week advisory threshold for mercury (0.30 ppm). Based on this
information, fish consumption uses are assessed (evaluated) as "fully
supported."
