Koeneman Park Lake
St. Louis County, MissouriView mapDirections
Missouri DNR publishes the water-quality measurements for Koeneman Park Lake. Here is what has been measured.
- Hypereutrophic
- Limited data
Koeneman Park Lake in St. Louis County, Missouri has water-quality measurements published by Missouri DNR, shown here as reported. Water clarity: 3.1 ft visibility. Phosphorus: 270.8 µg/L. Chlorophyll-a (algae): 35.9 µg/L.
Koeneman Park Lake is a highly nutrient-loaded hypereutrophic lake in St. Louis County, Missouri. Compared to the 4 other monitored lakes in St. Louis County, Koeneman Park Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, Missouri DNR, last sampled 2020-09-19. Methodology: how these readings are compared.
Swimming conditions
Readings onlyLimited data
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 Koeneman Park Lake is safe to swim in today is a call for the Missouri Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Koeneman Park Lake
These are the measurements Missouri DNR publishes for Koeneman Park Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 3.1 ft of visibility. Phosphorus 270.8 µg/L. Chlorophyll-a 35.9 µg/L. TSI 70.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 271µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 35.9µg/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. | 70 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Koeneman Park Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Koeneman Park Lake typically sits around 81°F at the surface in September. Summer average is about 84°F. Usually warmest in Jul (about 85°F) and coldest in Apr (about 69°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (69°F) to its warmest (85°F).
Typical surface water temperature by month, from 62 field readings (2010–2020) via the EPA Water Quality Portal. See the full Koeneman Park Lake water temperature breakdown →
Stays via Stay22
Stays near Koeneman Park Lake
Compare lakeside cabins, hotels, and vacation rentals near Koeneman Park Lake in St. Louis County, Missouri — 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 Koeneman Park Lake are listed below.
Top-rated places to stay near Koeneman Park Lake
Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Missouri’s top lakes →
Follow Koeneman Park Lake’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing Koeneman Park Lake
Regulated Pollution Sources Nearby
16 EPA-permitted facilities operate within about 5 miles of Koeneman Park Lake under Clean Water Act (NPDES) discharge permits.
- Abf Freight System IncSt Louis · 1.5 mi away · NPDES MONX00891
- City Of Bellefontaine NeighborsSt. Louis · 1.8 mi away · NPDES MONX00332
- Stlco Maintenance District OneFlorissant · 3 mi away · NPDES MONX00330
- Performance Foodservice MiddendorfBerkeley · 3.1 mi away · NPDES MONX01042
- Ups Scs St LouisSt Louis · 4.1 mi away · NPDES MONX00582
- Monarch Advanced SciencesBerkeley · 4.1 mi away · NPDES MONX00819
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.
Nearby Lakes in St. Louis County
Frequently asked questions about Koeneman Park Lake
Where is Koeneman Park Lake?
- Koeneman Park Lake is a lake in St. Louis County, Missouri. Its water-quality measurements are published by Missouri DNR and shown on this page as reported.
What is the water quality of Koeneman Park Lake?
- Koeneman Park Lake in St. Louis County, Missouri has water-quality measurements published by Missouri DNR, shown here as reported. Water clarity: 3.1 ft visibility. Phosphorus: 270.8 µg/L. Chlorophyll-a (algae): 35.9 µg/L.
Is Koeneman Park Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Koeneman Park Lake?
- Koeneman Park Lake typically sits around 81°F at the surface in September, from 62 EPA Water Quality Portal field readings (2010–2020). That is a typical value for the month, not a live reading.
Explore Koeneman Park Lake across LakeQuality
Planning a trip around Gateway Arch?
Koeneman Park Lake is about 9 miles from Gateway Arch National Park. Crowds there swing hard by season, so the month you pick changes both how busy the park is and what lodging costs.
Best time to visit Gateway Arch →More lakes in Missouri
Other Lakes in Missouri
Hypereutrophic Lakes in Missouri
Where this data comes from
15 measurements from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Univ. of Missouri, Columbia
UMC15 samples · 2020
Analytical methods
- Depth, Secchi disk in meters
- 4500 P E ~ Phosphorus in Water by Colorimetry- Ascorbic Acid Method
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
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.
Other records on this page
Regulated discharger data from EPA ECHO (ICIS-NPDES)