Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Dry Run IA 02-CED-554

mouth (S18 T89N R13W Black Hawk Co.) to confluence with unnamed tributary in S23 T89N R14W BlackHawk Co

Cycle
2020
Release Status
Final
Overall IR
5 - Water is impaired or threatened and a TMDL is needed.
Trend
Unknown
Created
8/31/2020 2:08:33 PM
Updated
10/16/2020 9:23:22 AM
Use Support
Class A1
Recreation - Primary contact
Partially Supported
Support Level
Partially Supported
Impairment Code
5a - Pollutant-caused impairment. TMDL needed.
Cause Magnitude
Moderate
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
N/A
Cycle Added
2008
Impairment Rationale
Geometric mean criterion exceeded
Data Source
Special project/study
TMDL Priority
Tier III
Class BWW2
Aquatic Life - Warm Water Type 2
Partially Supported
Support Level
Partially Supported
Impairment Code
5b-v - Biological - verified
Cause Magnitude
Slight
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
Low
Cycle Added
2004
Impairment Rationale
Low Biotic Index
Data Source
Biological monitoring: Iowa DNR WQMA
TMDL Priority
Tier IV
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

The Class A1 use remains assessed as "partially supported” due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. The Class BWW2 use was assessed as "partially supported" based on biological sampling data.

Assessment Explanation

Sources of Data:

Data Source

Data Source ID

Data Type

Data Age

Site ID

Site Name

Site Description

Iowa DNR

6

WQ

CY2012-2014

11070006

Dry Run Creek

DRC-1

Iowa DNR

6

WQ

CY2012-2014

11070007

Dry Run Creek

DRC-4

Iowa DNR

6

WQ

CY2012-2014

15070002

Dry Run Creek

DRC-3

Iowa DNR

6

BIO

See Below

215

Dry Run Creek

DS of Waterloo RD – DRC1

Iowa DNR

6

BIO

See Below

455

Dry Run Creek

US of University AVE near UNI Campus – DRC4


Class A1 - Indicator Bacteria:

Site ID

Data Source ID

# Samples / # Years

2012 Geometric Mean

2013 Geometric Mean

2014 Geometric Mean

Annual Geometric Mean Violation

# Violations

% Violations

Significantly >10% Violations

Assessment Type

Support Level

11070006

6

23 / 3

513

1114

320

Yes

15

65%

Yes

Evaluated

Not

11070007

6

24 / 3

170

435

238

Yes

11

46%

Yes

Evaluated

Partial

15070002

6

24 / 3

317

921

232

Yes

11

46%

Yes

Evaluated

Partial


Class A1 - pH:

Site ID

Data Source ID

# Samples / # Years

Maximum Value

Mean Value

Median Value

# Violations

% Violations

Significantly >10% Violations

Assessment Type

Support Level

11070006

6

17 / 2

8.4

8.1

8.2

0

0%

No

Evaluated

Full

11070007

6

17 / 2

8.3

7.9

8

0

0%

No

Evaluated

Full

15070002

6

16 / 2

8.4

8.1

8.2

0

0%

No

Evaluated

Full


Class BWW2 - Conventional Parameters:

Site ID

Data Source ID

Parameter Name

# Samples / # Years

Maximum Value

Mean Value

Median Value

# Acute / Chronic Violations

% Acute/ Chronic Violations

Significantly >10% Violations

Assessment Type

Support Level

11070006

6

Chloride

16 / 2

76

42

38

0 / 0

0% / 0%

No

Evaluated

Full

11070006

6

Dissolved oxygen

19 / 2

13

10.2

10.2

NA / 0

NA / 0%

No

Evaluated

Full

11070006

6

pH

17 / 2

8.4

8.1

8.2

0 / NA

0% / NA

No

Evaluated

Full

11070006

6

Temperature

19 / 2

19.5

15.3

16.2

0 / 0

0% / 0%

No

Evaluated

Full

11070007

6

Chloride

19 / 2

76

43

41

0 / 0

0% / 0%

No

Evaluated

Full

11070007

6

Dissolved oxygen

19 / 2

18.4

9.8

8.8

NA / 0

NA / 0%

No

Evaluated

Full

11070007

6

pH

17 / 2

8.3

7.9

8

0 / NA

0% / NA

No

Evaluated

Full

11070007

6

Temperature

19 / 2

19.3

14.4

14.9

0 / 0

0% / 0%

No

Evaluated

Full

15070002

6

Chloride

18 / 2

63

46

47

0 / 0

0% / 0%

No

Evaluated

Full

15070002

6

Dissolved oxygen

18 / 2

17.8

10.8

10.2

NA / 0

NA / 0%

No

Evaluated

Full

15070002

6

pH

16 / 2

8.4

8.1

8.2

0 / NA

0% / NA

No

Evaluated

Full

15070002

6

Temperature

18 / 2

19.8

15.8

15.9

0 / 0

0% / 0%

No

Evaluated

Full


Class BWW2 - Biological Sampling:

Benthic Macroinvertebrates:

BioNet Site ID

Date

Drainage Area (mi2)

Ecoregion

Major Drainage

BM Sample Gear

BMIBI score

BMIBI Class

47c BMIBI BIT

BMIBI Pass/ Fail

455

8/16/18

9

47c

MS/WW

Hess

53

Fair

70

Fail

455

7/26/16

9

47c

MS/WW

Hess

55

Fair

70

Fail

Fish:

BioNet Site ID

Date

Drainage Area (mi2)

Ecoregion

Major Drainage

Riffle Stream?

FIBI score

FIBI Class

47c FIBI BIT

FIBI Pass/ Fail

455

8/16/18

9

47c

MS/WW

Yes

24

Poor

65

Fail

215

8/16/18

24

47c

MS/WW

No

77

Excellent

44

Pass

455

7/26/16

9

47c

MS/WW

Yes

46

Fair

65

Fail

455

7/30/15

9

47c

MS/WW

Yes

55

Good

65

Fail

Overall:

Community

Assessment Type

Assessment Result

Support Level

Earned IR Category

Actual IR Category

Reason

Benthic Macroinvertebrates

Monitored

Fail (0/2)

Partial

Fish

Monitored

Fail (1/4)

Partial

Overall

Monitored

Fail

Partial

5bv

5bv

Assessment is monitored because it used samples collected in the last five years.

Monitoring and Methods
Assessment Key Dates
7/26/2016
Biological Monitoring
8/27/2012
Non-fixed Monitoring Start Date
10/28/2014
Non-fixed Monitoring End Date
8/16/2018
Biological Monitoring
7/30/2015
Biological Monitoring
Methods
150
Monitoring data more than 5 years old
220
Non-fixed station physical/chemical monitoring (conventional pollutant only)
315
Regional reference site approach
320
Benthic macroinvertebrate surveys
330
Fish surveys
420
Indicator bacteria monitoring