What is the water quality grade for Port Perry Lake South Arm?

Port Perry Lake South Arm in Perry County, Wisconsin received a water quality grade of B (Good). Water clarity: 9.5 ft visibility. Phosphorus: 8.3 µg/L. Chlorophyll-a (algae): 2.3 µg/L. Surface area: 187 acres.

Is Port Perry Lake South Arm safe to swim in?

Good for swimming, clear water with low algae levels. Port Perry Lake South Arm has an overall water quality grade of B. Algae concentration (chlorophyll-a) is 2.3 µg/L. Always check local health department advisories before swimming.

Port Perry Lake South Arm

Perry County, WisconsinOligotrophic

Port Perry Lake South Arm is a 187-acre cold, clear oligotrophic lake in Perry County, MO. Water quality is graded B based on 3 sampling years through 2024. Compared to the 2 other monitored lakes in Perry County, Port Perry Lake South Arm ranks #3 for water quality.

Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-09-17. Grade methodology: LakeGrade methodology.

Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

Moderate clarity, visible to about 9.5 ft. Phosphorus level: 8.3 µg/L. Chlorophyll-a: 2.3 µg/L. Trophic State Index: 39.

Metric	Value	Grade
Water Clarity (Secchi Depth)	9.5 ft	C
Phosphorus	8.3 µg/L	A
Chlorophyll-a (Algae)	2.3 µg/L	A
Trophic State Index (TSI)	39	Oligotrophic

Low nutrients, clear water, excellent for swimming

Lake Details

Characteristic	Value
Surface Area	187 acres

Location

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County Ranking

Ranked #3 of 3 lakes in Perry County

Cleaner Lakes Within 30 Miles

Port Perry Lake South Arm holds Grade B. 2 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Perry County

Port Perry Lake

Perry County

Port Perry Lake North Arm

Perry County

Goose Creek Lake

Ste. Genevieve County

Shepard Mountain Lake Intake

Iron County

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Top 25 by overall water quality score

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Other Grade B Lakes in Wisconsin

Table Rock Lake

Taney County · Clarity: 10 ft

Whippoorwill Lake

Warren County · Clarity: 5 ft

Lake Taneycomo @ Rockaway Beach

Taney County · Clarity: 8.7 ft

Forest Lake

Adair County · Clarity: 4.1 ft

Fox Valley Lake

Clark County · Clarity: 8.5 ft

Sherwood Lake Nr. Dam

Warren County · Clarity: 5.9 ft

Oligotrophic Lakes in Wisconsin

Lake Taneycomo @ Rockaway Beach Lake Wauwanoka Nr. Dam Lake Marseilles-Terre du Lac Lakes Lake Shayne-Terre du Lac Lakes

Reservoir Info (USACE NID)

Port Perry Lake South Arm is a man-made reservoir impounded by the Port Perry Dam (completed 1973), built primarily for recreation on the TR NATIONS CREEK; earth-type dam, 70 ft tall and 900 ft long.

Surface area: 187 ac
Normal storage: 828 ac-ft
Max storage: 6,506 ac-ft
Drainage area: 3.11 sq mi
Hazard class: High

Source: USACE National Inventory of Dams, NID ID MO30030 · Operator website · Matched by proximity (0.73 km)

Data Sources

Water quality data from the EPA Water Quality Portal

Grading methodology based on Metropolitan Council standards

Most recent sample: 2024-09-17

Monitoring stations: 1