Where is Avenue of the Saints Lake?

Avenue of the Saints Lake is a lake in Bremer County, Iowa. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.

What is the water temperature of Avenue of the Saints Lake?

Avenue of the Saints Lake typically sits around 72°F at the surface in September, from 31 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.

Avenue of the Saints Lake

Bremer County, IowaView map Directions

Algae-prone

Nutrients and algae run well above the regional average.

Water temp

~72°F

Typical for Sep · EPA WQP

Clarity

1.2 ft

Secchi · sampled 2024

Level

No gauge

Trend

Improving

4 years of samples

Hypereutrophic
Impaired · Algal growth
#1 of 1 in the county
Public access

See the measurements Directions Where to stay

Avenue of the Saints Lake in Bremer County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1.2 ft visibility. Phosphorus: 174.5 µg/L. Chlorophyll-a (algae): 89.7 µg/L.

Clarity: 1.2 ft
Typical in September: 72°F
Type: Hypereutrophic
Phosphorus: 174.5 µg/L
Chlorophyll-a: 89.7 µg/L
Trend: ↑ Improving
Public access: Yes

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Stays via Stay22

Stays near Avenue of the Saints Lake

Compare lakeside cabins, hotels, and vacation rentals near Avenue of the Saints Lake in Bremer County, Iowa — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Avenue of the Saints Lake are listed below.

Top-rated places to stay near Avenue of the Saints Lake

Prices for Sep 11–13, 4 adults. Change dates on the map below.

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Watch Avenue of the Saints Lake’s letter

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Free interactive depth-contour map of Avenue of the Saints Lake, reaching a maximum surveyed depth of 16 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.

Avenue of the Saints Lake is a highly nutrient-loaded hypereutrophic lake in Bremer County, Iowa. Water quality is graded F based on 2 sampling years through 2024. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available.

Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-10-28. Grade methodology: LakeQuality methodology.

Swimming Safety

Grade only

Algae risk

Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.

The F is nutrients and algae, not a swimming clearance. Avenue of the Saints Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for algal growth, pH / acidity, turbidity. Check local advisories before you swim.

Compare the safest swimming lakes near Cedar Rapids →

Get alerts for Avenue of the Saints Lake →

Water Quality Grade: F (Algae-prone)

Very murky, less than 1.2 ft of visibility. Phosphorus 174.5 µg/L. Chlorophyll-a 89.7 µg/L. TSI 76. The letter is not a swimming clearance.

Metric	Value	Grade
Water Clarity (Secchi Depth)	1.2 ft	Not graded
Phosphorus	174.5 µg/L	Poor
Chlorophyll-a (Algae)	89.7 µg/L	Poor
Trophic State Index (TSI)	76	Hypereutrophic

Very high nutrients, dense algae, poor clarity

Water Temperature

Avenue of the Saints Lake typically sits around 72°F at the surface in September. Summer average is about 77°F. Usually warmest in Jul (about 80°F) and coldest in May (about 62°F). These are typical values by month — not a live reading.

Jan

—

Feb

—

Mar

—

Apr

—

May

62°

Jun

74°

Jul

80°

Aug

77°

Sep

72°

Oct

—

Nov

—

Dec

—

Typical surface water temperature by month, from 31 field readings (2010–2023) via the EPA Water Quality Portal. See the full Avenue of the Saints Lake water temperature breakdown →

Fishing Avenue of the Saints Lake

→ Avenue of the Saints Lake fishing regulations (limits, seasons, special rules)

Water Quality Trend: ↑ Improving

Based on 4 years of monitoring data (2020-2025).

Metric	Trend	Change/Year	Years
Water Clarity	↑ Improving	+0.065 m/yr	4
Phosphorus	↑ Improving	-42.6 µg/L/yr	4
Chlorophyll-a	↓ Declining	+7.9 µg/L/yr	4

See year-by-year chart →

EPA Impairment Status

Avenue of the Saints Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).

Causes of impairment

Algal growthpH / acidityTurbidity

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit IA 02-SHL-1790 · Official waterbody report

Regulated Pollution Sources Nearby

7 EPA-permitted facilities operate within about 5 miles of Avenue of the Saints Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 6 facilities have a reported Clean Water Act violation in the past three years.

Waverly City Of Stp
Waverly · 3.8 mi away · NPDES IA0033197
MajorRecent violation
Shell Rock City Of Stp
Shell Rock · 2.3 mi away · NPDES IA0033359
Recent violation
Wartburg College
Waverly · 3 mi away · NPDES IA0071714
Recent violation
Waverly Municipal Fire Department
Waverly · 3.4 mi away · NPDES IA0080268
Recent violation
Poet Biorefining - Shell Rock, Llc
Shell Rock · 4.4 mi away · NPDES IA0081272
Recent violation
Shell Rock Soy Processing Llc
Shell Rock · 4.6 mi away · NPDES IA0053366
Recent violation

Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.

County Ranking

Ranked #1 of 1 lakes in Bremer County

Nearby Lakes With Higher Grades

Avenue of the Saints Lake holds Grade F. 2 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.

CGreen Belt Lake· 17.6 mi CMitchell Lake· 19.7 mi

See full comparison →

Nearby Lakes in Bremer County

FAlice Wyth Lake1.6 ft clear · Hypereutrophic13.7 miView →DFisher Lake2.6 ft clear · Eutrophic13.6 miView →NRGeorge Wyth Beach Lake13.8 miView →FSouth Prairie Lake1.6 ft clear · Hypereutrophic16.5 miView →NRCedar Lake—View →CGreen Belt Lake2.4 ft clear · Eutrophic17.6 miView →

Frequently asked questions about Avenue of the Saints Lake

Where is Avenue of the Saints Lake?: Avenue of the Saints Lake is a lake in Bremer County, Iowa. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Avenue of the Saints Lake?: Avenue of the Saints Lake in Bremer County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1.2 ft visibility. Phosphorus: 174.5 µg/L. Chlorophyll-a (algae): 89.7 µg/L.
Is Avenue of the Saints Lake safe to swim in?: The F is nutrients and algae, not a swimming clearance. Avenue of the Saints Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for algal growth, pH / acidity, turbidity. Check local advisories before you swim.
What is the water temperature of Avenue of the Saints Lake?: Avenue of the Saints Lake typically sits around 72°F at the surface in September, from 31 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.

Explore Avenue of the Saints Lake across LakeQuality

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Other Grade F Lakes in Iowa

Alice Wyth Lake

Black Hawk County · 1.6 ft

South Prairie Lake

Black Hawk County · 1.6 ft

Meyers Lake

Black Hawk County · 1.1 ft

Casey Lake

Tama County · 1.2 ft

Union Grove Lake

Tama County · 1.6 ft

Upper Pine Lake

Hardin County · 1.3 ft

Hypereutrophic Lakes in Iowa

Alice Wyth Lake South Prairie Lake Meyers Lake Casey Lake

Where this data comes from

66 measurements from 1 monitoring station, 2021–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

Iowa DNR Surface Water Monitoring Data21IOWA_WQX66 samples · 2021–2024

Analytical methods

Unknown
Phosphorus by Colorimetry
445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
In-Vitro Determination of Chlorophyll
ISU modification of APHA 2130-B

Monitoring station identifiers (1)

21IOWA_WQX-22090001

Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.