Lake Konstanz
Warren County, Missouri19 acresView mapDirections
Clarity, phosphorus, and algae all sit in the cleanest band for this region.
↑ up from B at the last regrade
- Oligotrophic
- #2 of 16 in the county
Lake Konstanz in Warren County, Missouri has a water quality grade of A (Excellent). Water clarity: 7.7 ft visibility. Phosphorus: 7 µg/L. Chlorophyll-a (algae): 1.6 µg/L. Surface area: 19 acres.
- Clarity
- 7.7 ft
- Typical in September
- 78°F
- Area
- 19 acres
- Type
- Oligotrophic
- Phosphorus
- 7 µg/L
- Chlorophyll-a
- 1.6 µg/L
- Trend
- ↑ Improving
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Watch Lake Konstanz’s letter
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Lake Konstanz is a 19-acre cold, clear oligotrophic lake in Warren County, Missouri. Water quality is graded A based on 2 sampling years through 2024. Overall water quality is improving over recent sampling years. Compared to the 15 other monitored lakes in Warren County, Lake Konstanz ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Missouri DNR, last sampled 2024-09-19. Grade methodology: LakeQuality methodology.
Swimming Safety
Grade onlyLow algae
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 A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: A (Excellent)
Moderate clarity, visible to about 7.7 ft. Phosphorus 7 µg/L. Chlorophyll-a 1.6 µg/L. TSI 38. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 7.7 ft | Not graded |
| Phosphorus | 7 µg/L | Good |
| Chlorophyll-a (Algae) | 1.6 µg/L | Good |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water. The letter is not a swimming clearance.
Water Temperature
Lake Konstanz typically sits around 78°F at the surface in September. Summer average is about 82°F. Usually warmest in Jul (about 85°F) and coldest in Apr (about 63°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 148 field readings (2010–2024) via the EPA Water Quality Portal. See the full Lake Konstanz water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 19 acres |
No bathymetric survey has been published for Lake Konstanz, so its depth is not documented here.
Fishing Lake Konstanz
Water Quality Trend: ↑ Improving
Based on 4 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.254 m/yr | 4 |
| Phosphorus | ↑ Improving | -1.17 µg/L/yr | 4 |
| Chlorophyll-a | ↑ Improving | -0.27 µg/L/yr | 4 |
Reservoir Info (USACE NID)
Lake Konstanz is a man-made reservoir impounded by the Lake Konstanz Dam (completed 1999) on the TRIB. CHARRETTE CREEK; earth-type dam, 90 ft tall and 525 ft long.
- Surface area
- 19 ac
- Normal storage
- 86 ac-ft
- Max storage
- 103 ac-ft
- Drainage area
- 0.14 sq mi
- Hazard class
- High
- Owner
- INNSBROOK CORPORATION
Source: USACE National Inventory of Dams, NID ID MO32048 · Operator website
Regulated Pollution Sources Nearby
3 EPA-permitted facilities operate within about 5 miles of Lake Konstanz under Clean Water Act (NPDES) discharge permits. 3 facilities have a reported Clean Water Act violation in the past three years.
- Dogwood Lake CampgroundWarrenton · 3.8 mi away · NPDES MO0085863Recent violation
- Oak Grove MhpWarrenton · 4.3 mi away · NPDES MO0088111Recent violation
- Oak Ridge Estates WwtfWarrenton · 4.7 mi away · NPDES MO0123391Recent 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 #2 of 16 lakes in Warren County
Nearby Lakes in Warren County
Frequently asked questions about Lake Konstanz
Where is Lake Konstanz?
- Lake Konstanz is a lake in Warren County, Missouri. LakeQuality grades it A for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Lake Konstanz?
- Lake Konstanz in Warren County, Missouri has a water quality grade of A (Excellent). Water clarity: 7.7 ft visibility. Phosphorus: 7 µg/L. Chlorophyll-a (algae): 1.6 µg/L. Surface area: 19 acres.
Is Lake Konstanz safe to swim in?
- The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Lake Konstanz?
- Lake Konstanz typically sits around 78°F at the surface in September, from 148 EPA Water Quality Portal field readings (2010–2024). That is a typical value for the month, not a live reading.
Explore Lake Konstanz across LakeQuality
Species activity outlook by water temperature and season
Where to stay at Missouri's top lakes, each with its grade
Low nutrients, clear water. The letter is not a swimming clearance.
Missouri's cleanest and most-polluted lakes, ranked
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Other Grade A Lakes in Missouri
Oligotrophic Lakes in Missouri
Where this data comes from
66 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Univ. of Missouri, Columbia
UMC66 samples · 2020–2024
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)
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.
Other records on this page
Regulated discharger data from EPA ECHO (ICIS-NPDES)