Meadow Lake IA 04-LDM-1089

Adair County S17T76NR31W 5 mi N of Greenfield.

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: 8/13/2020 8:58:47 AM
Updated: 10/14/2020 11:43:19 AM

Use Support

Class A1

Recreation - Primary contact

Not Supported

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

Narrative criteria violation: aesthetically objectionable conditions

Cycle Delisted

2020

Delisting Rationale

TMDL preparation and approval

Data Source

Ambient monitoring: Iowa DNR-lakes

Class BLW

Aquatic Life - Lakes and wetlands

WINOFI

Algal Growth: Cyanobacteria

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

Low

Cycle Added

2002

Impairment Rationale

Adverse impacts on plant/animal communities

Data Source

Ambient monitoring: Iowa DNR-lakes

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 uses are assessed (monitored) as “not supported” due to aesthetically objectionable conditions caused by poor water transparency caused by algae blooms. The Class BLW uses are assessed (evaluated) as “partially supported” based on information from the IDNR Fisheries Bureau and results from the ISU lake surveys due to a large population of cyanobacteria. Class HH uses are assessed (monitored) as "fully supported" based on results of fish tissue monitoring. Note: A TMDL for Algae and Turbidity at Meadow Lake was prepared by DNR and approved by EPA in 2020. Because all Section 303(d) impairments identified in this assessment/listing cycle (algal and Turbidity) are addressed by the TMDL, Meadow Lake is placed in IR Category 4a (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	22010003	Meadow Lake	Lake Deep Point
Iowa DNR		FT	See Below	269	Meadow 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
22010003	6	15 / 5	9	8.4	8.4	0	0%	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
22010003	6	Chlorophyll a TSI	29 / 5	36	78	70	YES	Monitored	Not
22010003	6	Secchi TSI	15 / 5	51	83	73	YES	Monitored	Not
22010003	6	Total Phosphorus TSI	29 / 5	57	81	75	NA	NA	NA
22010003	6	Inorganic suspended solids	15 / 5	0.3	21	4	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
22010003	6	Ammonia	15 / 5	0.253	0.05	0.02	0 / 0	0% / 0%	NO	Monitored	Full
22010003	6	Dissolved oxygen	15 / 5	14.17	8.88	8.9	NA / 1	NA / 7%	NO	Monitored	Full
22010003	6	pH	15 / 5	9	8.4	8.4	0 / NA	0% / NA	NO	Monitored	Full
22010003	6	Temperature	15 / 5	29.4	24.19	23.9	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
22010003	6	11	273.254	99.7 %	29.225	85.9 %	YES	Evaluated	3b

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

269

6/19/17

largemouth bass

plug

0.230

Monitored

Full

269

8/8/14

largemouth bass

plug

0.050

Monitored

Full

NOTE: Meadow Lake was drawn down in the winter of 2008-2009 and sediment and nutrient retention structures were built in the watershed in 2010.

Monitoring and Methods

Assessment Key Dates

6/16/2014

Fixed Monitoring Start Date

8/30/2018

Fixed Monitoring End Date

6/19/2017

Fish Tissue Monitoring

8/8/2014

Fish Tissue Monitoring

3/25/2020

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)