Vernor Lake
Richland County, Illinois45 acresView mapDirections
Illinois EPA publishes the water-quality measurements for Vernor Lake. Here is what has been measured.
- Eutrophic
- Impaired · Algal growth
- 26 ft max depth
- Limited data
Vernor Lake in Richland County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Water clarity: 4.8 ft visibility. Phosphorus: 114 µg/L. Chlorophyll-a (algae): 29.1 µg/L. Surface area: 45 acres.
Vernor Lake is a 45-acre productive, nutrient-rich eutrophic lake in Richland County, Illinois with an estimated average depth of about 26 feet. Compared to the 2 other monitored lakes in Richland County, Vernor Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Illinois EPA, last sampled 2022-10-25. 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. Vernor Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Vernor Lake is safe to swim in today is a call for the Illinois Environmental Protection Agency and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Vernor Lake
These are the measurements Illinois EPA publishes for Vernor Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 4.8 ft. Phosphorus 114 µg/L. Chlorophyll-a 29.1 µg/L. TSI 64.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 4.8ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 114µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 29.1µg/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. | 64 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Vernor Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Vernor Lake typically sits around 59°F at the surface in October. Summer average is about 72°F. Usually warmest in Jul (about 75°F) and coldest in Oct (about 59°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (59°F) to its warmest (75°F).
Typical surface water temperature by month, from 217 field readings (2014–2022) via the EPA Water Quality Portal. See the full Vernor Lake water temperature breakdown →
Lake Details
Max depth
~26 ft est.
Surface area
45 acres
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Illinois has not published bathymetry for Vernor Lake.
Lake Size & Watershed
Watershed (drainage) area
19 sq mi
HydroLAKES / HydroSHEDS
Shoreline
1.2 mi
HydroLAKES / HydroSHEDS
Elevation
456 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Stays via Stay22
Stays near Vernor Lake
Compare lakeside cabins, hotels, and vacation rentals near Vernor Lake in Richland County, Illinois — 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 Vernor Lake are listed below.
Top-rated places to stay near Vernor Lake
Prices for Oct 23–25, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Illinois’s top lakes →
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Fishing Vernor Lake
Reservoir Info (USACE NID)
Vernor Lake is a man-made reservoir impounded by the Vernor Lake Dam (completed 1924), built primarily for recreation on the TRIB FOX RIVER; earth-type dam, 42 ft tall and 820 ft long.
- Surface area
- 45 ac
- Normal storage
- 900 ac-ft
- Max storage
- 972 ac-ft
- Drainage area
- 0.4 sq mi
- Hazard class
- Significant
- Owner
- CITY OF OLNEY
All listed purposes: Recreation;Water Supply.
Source: USACE National Inventory of Dams, NID ID IL00793 · Operator website
EPA Impairment Status
Vernor Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption, Other.
Source: EPA ATTAINS assessment unit IL_RCA · Official waterbody report
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Vernor Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 2 facilities have a reported Clean Water Act violation in the past three years.
- Olney Stp, City OfOlney · 3.2 mi away · NPDES IL0048755MajorRecent violation
- Kincaid Acres Mhp StpOlney · 0.2 mi away · NPDES IL0056146Recent 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.
Nearby Lakes in Richland County
Frequently asked questions about Vernor Lake
Where is Vernor Lake?
- Vernor Lake is a lake in Richland County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Vernor Lake?
- Vernor Lake in Richland County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Water clarity: 4.8 ft visibility. Phosphorus: 114 µg/L. Chlorophyll-a (algae): 29.1 µg/L. Surface area: 45 acres.
Is Vernor Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Vernor Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Vernor Lake?
- Vernor Lake typically sits around 59°F at the surface in October, from 217 EPA Water Quality Portal field readings (2014–2022). That is a typical value for the month, not a live reading.
How deep is Vernor Lake?
- No published bathymetric survey covers Vernor Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 26 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 45 acres.
Explore Vernor Lake across LakeQuality
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Where this data comes from
41 measurements from 3 monitoring stations, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- illinois epa
IL_EPA_WQX41 samples · 2022
Analytical methods
- MEASURED IN FIELD
- Phosphorus by Colorimetry
- 10200 H 2 ~ Chlorophyll a-b-c Determination by spectrophotometer
Monitoring station identifiers (3)
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
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)