South Lake
Johnson County, Kansas5 acresView mapDirections
KDHE publishes the water-quality measurements for South Lake. Here is what has been measured.
- Hypereutrophic
South Lake in Johnson County, Kansas has water-quality measurements published by KDHE, shown here as reported. Phosphorus: 177.2 µg/L. Chlorophyll-a (algae): 72 µg/L. Surface area: 5.2 acres.
South Lake is a 5-acre highly nutrient-loaded hypereutrophic lake in Johnson County, Kansas. Overall water quality is declining over recent sampling years. Compared to the 12 other monitored lakes in Johnson County, South Lake ranks #10 for water quality.
Source: EPA Water Quality Portal sampling records, KDHE, last sampled 2024-09-05. Methodology: how these readings are compared.
Swimming conditions
Readings onlyAlgae risk
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether South Lake is safe to swim in today is a call for the Kansas Department of Health and Environment and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for South Lake
These are the measurements KDHE publishes for South Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Phosphorus 177.2 µg/L. Chlorophyll-a 72 µg/L. TSI 76.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 177µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 72µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 76 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about South Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
5 acres
No bathymetric survey has been published for South Lake, so its depth is not documented here.
Stays via Stay22
Stays near South Lake
Compare lakeside cabins, hotels, and vacation rentals near South Lake in Johnson County, Kansas — 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 readings cover nutrients and algae, not lodging. Cabins and rentals around South Lake are listed below.
Top-rated places to stay near South Lake
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Fishing South Lake
Water Quality Trend: Worsening
Based on 11 years of monitoring (2012–2024).
Phosphorus
Worsening+15.63 µg/L/yr11 years
Chlorophyll-a
Worsening+2.58 µg/L/yr11 years
Reservoir Info (USACE NID)
South Lake is a man-made reservoir impounded by the South Lake Park Dam, built primarily for recreation on the Indian Creek-Tr; earth-type dam, 17 ft tall and 600 ft long.
- Surface area
- 5.2 ac
- Normal storage
- 17.3 ac-ft
- Max storage
- 66 ac-ft
- Drainage area
- 0.3 sq mi
- Hazard class
- High
- Owner
- OVERLAND PARK, CITY OF
Source: USACE National Inventory of Dams, NID ID KS07293 · Operator website · Matched by proximity (0.01 km)
Nearby Lakes in Johnson County
Frequently asked questions about South Lake
Where is South Lake?
- South Lake is a lake in Johnson County, Kansas. Its water-quality measurements are published by KDHE and shown on this page as reported.
What is the water quality of South Lake?
- South Lake in Johnson County, Kansas has water-quality measurements published by KDHE, shown here as reported. Phosphorus: 177.2 µg/L. Chlorophyll-a (algae): 72 µg/L. Surface area: 5.2 acres.
Is South Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Explore South Lake across LakeQuality
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Other Lakes in Kansas
Hypereutrophic Lakes in Kansas
Where this data comes from
91 measurements from 1 monitoring station, 2012–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- EPA R7
EPA_R7_WQX91 samples · 2012–2024
Analytical methods
- Nutrient Analysis
- Total Phosphorus After Block Digestion
- Chlorophyll a
- Fluorometric Analysis of Chlorophyll a (originally 2334.22A)
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- Total Nitrogen Calculation
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.