Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Cold Springs Lake IA 05-NSH-1420

Cass County S15T75NR37W 1 mi S of Lewis.

Cycle
2020
Release Status
Final
Overall IR
1 - All designated uses are met.
Trophic
Eutrophic
Trend
Stable
Created
8/26/2020 11:21:04 AM
Updated
10/15/2020 7:47:10 AM
Use Support
Class A1
Recreation - Primary contact
Fully Supported
Class BLW
Aquatic Life - Lakes and wetlands
Fully Supported
Class HH
Human Health -
Fully Supported
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

The Class A1 use is assessed (monitored) as “fully supported." The Class BLW use is assessed (monitored) as “fully supported.” Class HH use is assessed (monitored) as “fully supported” based on fish tissue sampling.

Assessment Explanation

Sources of Data:

Data Source

Data Source ID

Data Type

Data Age

Site ID

Site Name

Site Description

Iowa DNR

6

WQ

CY 2014-2018

22150001

Cold Springs Lake

Lake Deep Point

Iowa DNR

FT

See Below

289

Cold Springs Lake


Class A1 - Indicator Bacteria: No Data


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

22150001

6

15 / 5

9.4

8.6

8.7

2

13%

NO

Monitored

Full


Class A1 - Lake TSI's

Site ID

Data Source ID

Parameter Name

# Samples / # Years

Minimum Value

Maximum Value

Median Value

Median TSI Violation

Assessment Type

Support Level

22150001

6

Chlorophyll a TSI

15 / 5

36

76

61

NO

Monitored

Full

22150001

6

Secchi TSI

15 / 5

43

71

62

NO

Monitored

Full

22150001

6

Total Phosphorus TSI

15 / 5

44

71

64

NA

NA

NA

22150001

6

Inorganic suspended solids

15 / 5

0.3

26

2.5

NA

NA

NA


Class BLW - 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

22150001

6

Ammonia

15 / 5

0.293

0.06

0.03

0 / 0

0% / 0%

NO

Monitored

Full

22150001

6

Dissolved oxygen

15 / 5

13.31

8.6

8.3

NA / 1

NA / 7%

NO

Monitored

Full

22150001

6

pH

15 / 5

9.4

8.6

8.7

2 / NA

13% / NA

NO

Monitored

Full

22150001

6

Temperature

15 / 5

29.2

24.98

24.8

0 / 0

0% / 0%

NO

Monitored

Full


Class BLW - Lake Planktonic Cyanobacteria:

Site ID

Data Source ID

# Samples

Maximum Cyanobacteria Wet Mass

Maximum Cyanobacteria % Composition

Median Cyanobacteria Wet Mass

Median Cyanobacteria % Composition

Median Cyanobacteria Wet Mass = 75th Percentile

Assessment Type

Support Level

22150001

6

11

56.178

97.7 %

10.827

50.2 %

NO

Evaluated

NA


Class HH - Fish Tissue Sampling:

Site ID

Date

Species Name

Biopart

# in sample

chlordane result

chlordane violation?

PCBs result

PCBs violation?

Hg result

Hg violation?

Assessment Type

Support Level

289

6/9/17

largemouth bass

plug

3

0.230

No

Monitored

Full

289

8/8/14

largemouth bass

plug

5

0.160

No

Monitored

Full

Note: According to Iowa DNR Fisheries Biologists,the clear water and shallow lake basin of Cold Springs Lakes has been ideal for growing aquatic plants. In 2014, a dye treatment was used to suppress aquatic plant growth. It worked very well reducing plant and algae growth down to an acceptable level. The dye treatment was repeated in 2015 with poor results. In 2016 the dye was applied at a higher rate in hopes to repeat 2014 results and it is working. Curly leaf pondweed an invasive plant showed up in Cold Springs a few years ago. Curly leaf pondweed has been on the increase ever since. In other lakes, curly leaf emerges early, crowds out native plants, and dies off in late June promoting algae blooms.

Monitoring and Methods
Assessment Key Dates
6/18/2014
Fixed Monitoring Start Date
8/26/2018
Fixed Monitoring End Date
6/9/2017
Fish Tissue Monitoring
8/8/2014
Fish Tissue Monitoring
Methods
120
Surveys of fish and game biologists/other professionals
222
Non-fixed-station monitoring (conventional during key seasons and flows)
260
Fish tissue analysis
340
Primary producer surveys (phytoplankton/periphyton/macrophyton)