Avenue Of The Saints Lake IA 02-SHL-1790

Bremer Co. approximately 2 miles E of Shell Rock in S7 T91N R14W

Open Data Collection Period Modal

For purposes of developing stream/river water quality assessments for integrated reporting, three years of water quality data are typically used for both conventional pollutant parameters (e.g., indicator bacteria) and the less frequently monitored toxic parameters (e.g., toxic metals). Since the 2004 IR cycle, DNR has used a three-year data gathering period for streams, rivers, and beaches. For most assessments, the use of three years of data increases the number of samples upon which the decision on use support is based and helps address the problem of weather-related year-to-year fluctuations in water quality.

Due to the lower sampling frequency in Iowa’s ambient lake, biological, fish kill, and fish tissue monitoring programs, five years of data are used for developing IR assessments and for identifying Section 303(d) listings.

Data Type	Data Timeframe
Beach Sampling Data	CY 2016 - 2018
Stream/River Water Quality Data	CY 2016 - 2018
Lake Water Quality Data	CY 2014 - 2018
Biological Sampling Data	CY 2014 - 2018*
Fish Kill Data	CY 2014 - 2018
Fish Tissue Sampling Data	CY 2014 - 2018
Continuous Dissolved Oxygen Sampling Data	CY 2014 - 2018
*Biological sites sampled in both 2013 and 2017 were also assessed.

Open Segment Map
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Cycle: 2020
Release Status: Final
Overall IR: 4 - Water is impaired or threatened and a TMDL has been completed or is not needed.
Trophic: Hypereutrophic
Trend: Stable
Created: 9/1/2020 2:30:06 PM
Updated: 10/15/2020 11:12:03 AM

Use Support

Class BLW

Aquatic Life - Lakes and wetlands

Not Supported

Support Level

Not Supported

Impairment Code

4a - Pollutant-caused impairment. TMDL has been completed.

Cause Magnitude

Moderate

Status

Delisted

Source

Natural: Internal Nutrient Recycling (Primarily Lakes)

Source Confidence

Low

Cycle Added

2016

Impairment Rationale

Adverse impacts on plant/animal communities

Cycle Delisted

2020

Delisting Rationale

TMDL preparation and approval

Data Source

TMDL monitoring: Iowa DNR

Algal Growth: Chlorophyll a

Support Level

Not Supported

Impairment Code

4a - Pollutant-caused impairment. TMDL has been completed.

Cause Magnitude

Moderate

Status

Delisted

Source

Agriculture

Source Confidence

Moderate

Cycle Added

2004

Impairment Rationale

Adverse impacts on plant/animal communities

Cycle Delisted

2020

Delisting Rationale

TMDL preparation and approval

Data Source

TMDL monitoring: Iowa DNR

Turbidity

Support Level

Not Supported

Impairment Code

4a - Pollutant-caused impairment. TMDL has been completed.

Cause Magnitude

Moderate

Status

Delisted

Source

Hydromodification: Erosion and Sedimentation

Source Confidence

Moderate

Cycle Added

2004

Impairment Rationale

Adverse impacts on plant/animal communities

Cycle Delisted

2020

Delisting Rationale

TMDL preparation and approval

Data Source

TMDL monitoring: Iowa DNR

Fish Kill: Due To Natural Causes

Support Level

Further Investigation Needed

Impairment Code

3b - Use potentially impaired based on an evaluated assessment.

Cause Magnitude

Slight

Status

Continuing

Source

Natural: Natural Sources

Source Confidence

Low

Cycle Added

2016

Impairment Rationale

Potential Impairment

Data Source

Fish kill investigation: Iowa DNR

Class HH

Human Health -

WINOFI

Metals: Mercury

Support Level

Further Investigation Needed

Impairment Code

3b - Use potentially impaired based on an evaluated assessment.

Cause Magnitude

Slight

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2016

Impairment Rationale

Potential fish consumption advisory; additional sampling needed

Data Source

Fish contaminant monitoring: Iowa DNR

General Use

General Use water -

Not Assessed

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

This lake is not designated for Class A1 primary contact recreation uses. The Class BLW uses are assessed (monitored) as "not supported." Information from the IDNR Fisheries Bureau suggests poor water transparency due to algae and inorganic turbidity (suspended solids) have led to a poor fishery that suggests an impairment of the aquatic life uses. In addition, a fish kill occurred at this lake thus suggesting a potential impairment of the Class BLW uses. Class HH uses are assessed as "partially supporting" due to the potential of a fish consumption advisory. Note: A TMDL for algae, turbidity, and pH at Avenue of the Saints Lake was prepared by DNR and approved by EPA in 2019. Because all Section 303(d) impairments identified for the current assessment/listing cycle (algal growth, turbidity, and pH) are addressed by the TMDL, this waterbody is placed in IR Category 4a (impaired; TMDL approved).

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	22090001	Avenue of the Saints Lake	Lake Deep Point
Iowa DNR		FT	See Below	282	Avenue of the Saints Lake

Class BLW - 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
22090001	6	Chlorophyll a TSI	15 / 5	44	85	68	YES	Monitored	Not
22090001	6	Secchi TSI	15 / 5	67	77	73	YES	Monitored	Not
22090001	6	Total Phosphorus TSI	15 / 5	69	96	81	NA	NA	NA
22090001	6	Inorganic suspended solids	15 / 5	2	23.5	9	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
22090001	6	Ammonia	15 / 5	0.47515	0.1	0.01	0 / 0	0% / 0%	NO	Monitored	Full
22090001	6	Dissolved oxygen	15 / 5	15.1	8.87	8.4	NA / 1	NA / 7%	NO	Monitored	Full
22090001	6	pH	15 / 5	10.1	8.9	8.9	7 / NA	47% / NA	YES	Monitored	Not
22090001	6	Temperature	15 / 5	27.2	23.9	23.8	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
22090001	6	11	643.909	100 %	66.761	93 %	YES	Evaluated	3b

Class BLW - Fish Kill:

The Class BLW uses are assessed (evaluated) as “partially supported” due to fish kills that occurred in May of 2015. Because the cause of the fish kill was not identified, or the fish kill was attributed to a non-pollutant cause (e.g., winterkill), the assessment type is “evaluated.” Segments assessed using “evaluated” assessments are placed in Category 3b and are added to the state list of waters in need of further investigation. If no additional fish kills are reported in the segment for a 10 year period, the Category will be changed from 3b to 3a (water not assessed).

Details about the 2015 fish kill can be found here: https://programs.iowadnr.gov/fishkill/Events/902

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

282

8/29/13

common carp

fillet

<0.2

<0.6

0.1

Evaluated

Full

282

8/29/13

largemouth bass

plug

0.786

Yes

Evaluated

Partial

According to DNR’s assessment methodology, the single occurrence of contaminant above an advisory trigger level neither warrants issuance of an advisory nor indicates impairment of the fish consumption uses: two consecutive samplings that show contaminant levels are above the trigger level in fillet samples are needed to justify issuance of an advisory. Thus, follow-up monitoring is needed at Avenue of the Saints Lake

Monitoring and Methods

Assessment Key Dates

6/9/2014

Fixed Monitoring Start Date

9/16/2018

Fixed Monitoring End Date

8/29/2013

Fish Tissue Monitoring

10/15/2019

TMDL Completed

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)