Washington Lake
Jackson County, MissouriView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- #22 of 23 in the county
- Limited data
Washington Lake in Jackson County, Missouri has a water quality grade of F (Algae-prone). Phosphorus: 116.6 µg/L. Chlorophyll-a (algae): 36.9 µg/L.
- Typical in August
- 77°F
- Type
- Hypereutrophic
- Phosphorus
- 116.6 µg/L
- Chlorophyll-a
- 36.9 µg/L
- Trend
- ↓ Declining
Stays via Stay22
Stays near Washington Lake
Compare lakeside cabins, hotels, and vacation rentals near Washington Lake in Jackson 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 grade measures nutrients and algae, not lodging — cabins and rentals around Washington Lake are listed below.
Top-rated places to stay near Washington Lake
Prices for Sep 11–13, 4 adults. Change dates on the map below.
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Watch Washington Lake’s letter
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Washington Lake is a highly nutrient-loaded hypereutrophic lake in Jackson County, Missouri. Water quality is graded F based on 3 sampling years through 2024. Overall water quality is declining over recent sampling years. Compared to the 22 other monitored lakes in Jackson County, Washington Lake ranks #22 for water quality.
Source: EPA Water Quality Portal sampling records, Missouri DNR, last sampled 2024-09-05. Grade methodology: LakeQuality methodology.
Swimming Safety
Grade onlyBacteria F
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.
Based on E. coli testing, Washington Lake routinely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 54.5% of 11 samples across 4 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Missouri’s current beach and health-department advisories before swimming.
Water Quality Grade: F (Algae-prone)
No clarity data. Phosphorus 116.6 µg/L. Chlorophyll-a 36.9 µg/L. TSI 69. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 116.6 µg/L | Poor |
| Chlorophyll-a (Algae) | 36.9 µg/L | Poor |
| Trophic State Index (TSI) | 69 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
Washington Lake typically sits around 77°F at the surface in August. Summer average is about 78°F. Usually warmest in Jul (about 81°F) and coldest in May (about 70°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 38 field readings (2010–2022) via the EPA Water Quality Portal. See the full Washington Lake water temperature breakdown →
Fishing Washington Lake
Water Quality Trend: ↓ Declining
Based on 3 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Phosphorus | ↓ Declining | +32.47 µg/L/yr | 3 |
| Chlorophyll-a | ↓ Declining | +4.59 µg/L/yr | 3 |
Regulated Pollution Sources Nearby
6 EPA-permitted facilities operate within about 5 miles of Washington Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 1 facility has a reported Clean Water Act violation in the past three years.
- Kc Westside WwtpKansas City · 2.3 mi away · NPDES MO0024929MajorRecent violation
- Holland Company, Dba M-Bar-DKansas City · 1.3 mi away · NPDES MO0127507
- First Transit Inc #55433Kansas City · 1.6 mi away · NPDES MONX00254
- Pbi Gordon Corp Glp And WarehouseKansas City · 1.6 mi away · NPDES MONX00657
- Pbi Gordon Corp R And D OfficeKansas City · 1.6 mi away · NPDES MONX00656
- Faultless BrandsKansas City · 2 mi away · NPDES MONX01050
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 #22 of 23 lakes in Jackson County
Nearby Lakes in Jackson County
Frequently asked questions about Washington Lake
Where is Washington Lake?
- Washington Lake is a lake in Jackson County, Missouri. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Washington Lake?
- Washington Lake in Jackson County, Missouri has a water quality grade of F (Algae-prone). Phosphorus: 116.6 µg/L. Chlorophyll-a (algae): 36.9 µg/L.
Is Washington Lake safe to swim in?
- Based on E. coli testing, Washington Lake routinely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 54.5% of 11 samples across 4 seasons. That works out to a bacteria swim-safety grade of F — a historical summary of past testing, not a current reading. Washington Lake has a water quality grade of F (Algae-prone). Bacteria levels can spike quickly after heavy rain, so always check Missouri's current beach and health-department advisories before you swim.
What is the water temperature of Washington Lake?
- Washington Lake typically sits around 77°F at the surface in August, from 38 EPA Water Quality Portal field readings (2010–2022). That is a typical value for the month, not a live reading.
Explore Washington Lake across LakeQuality
Species activity outlook by water temperature and season
Where to stay at Missouri's top lakes, each with its grade
Very high nutrients, dense algae, poor clarity
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Hypereutrophic Lakes in Missouri
Where this data comes from
29 measurements from 1 monitoring station, 2021–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- EPA R7
EPA_R7_WQX29 samples · 2021–2024
Analytical methods
- Total Phosphorus After Block Digestion
- Nutrient Analysis
- Chlorophyll a
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- Total Nitrogen Calculation
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)