Round Lake
Lake County, Illinois242 acresView mapDirections
Illinois EPA publishes the water-quality measurements for Round Lake. Here is what has been measured.
- Eutrophic
- 32 ft max depth
- Public access
- Limited data
Round Lake in Lake County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Water clarity: 7.4 ft visibility. Phosphorus: 20.5 µg/L. Chlorophyll-a (algae): 7.1 µg/L. Surface area: 242 acres.
Round Lake is a 242-acre productive, nutrient-rich eutrophic lake in Lake County, Illinois with an estimated average depth of about 32 feet. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 18 other monitored lakes in Lake County, Round Lake ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, Illinois EPA, last sampled 2022-10-12. Methodology: how these readings are compared.
Round Lake covers about 240 acres in Lake County. It has one public boat landing. If you are planning to stay, you can search lake houses and cabins around Round Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Round Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
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 Round 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 Round Lake
These are the measurements Illinois EPA publishes for Round Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 7.4 ft. Phosphorus 20.5 µg/L. Chlorophyll-a 7.1 µg/L. TSI 49.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7.4ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 20.5µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 7.1µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 49 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Round Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Round Lake typically sits around 60°F at the surface in October. Summer average is about 72°F. Usually warmest in Jul (about 75°F) and coldest in May (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 380 field readings (2012–2022) via the EPA Water Quality Portal. See the full Round Lake water temperature breakdown →
Lake Details
Max depth
~32 ft est.
Surface area
242 acres
Public access
Yes
Listed by Illinois EPA
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Illinois has not published bathymetry for Round Lake.
Lake Size & Watershed
Watershed (drainage) area
3 sq mi
HydroLAKES / HydroSHEDS
Shoreline
2.3 mi
HydroLAKES / HydroSHEDS
Elevation
768 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.
Recreation & Access
- Lakefront ParkPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Round Lake
Compare lakeside cabins, hotels, and vacation rentals near Round Lake in Lake 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.
Top-rated places to stay near Round Lake
Prices for Oct 23–25, 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 trip? Cabins and lodging at Round Lake → · more Illinois lake trips
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Fishing Round Lake
Reservoir Info (USACE NID)
Round Lake is a man-made reservoir impounded by the Round Lake Dam (completed 1945), built primarily for recreation on the TRIB SQUAW CREEK; earth-type dam, 9 ft tall and 140 ft long.
- Surface area
- 242 ac
- Normal storage
- 976 ac-ft
- Max storage
- 1,484 ac-ft
- Drainage area
- 2.5 sq mi
- Hazard class
- Significant
- Owner
- VILLAGE OF ROUND LAKE BEACH
Source: USACE National Inventory of Dams, NID ID IL00593 · Operator website
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Round Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Fonks Home Center, Inc. - Hickory HavenKansasville · 3.4 mi away · NPDES WI0030660Recent 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 Lake County
Frequently asked questions about Round Lake
Where is Round Lake?
- Round Lake is a lake in Lake County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Round Lake?
- Round Lake in Lake County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Water clarity: 7.4 ft visibility. Phosphorus: 20.5 µg/L. Chlorophyll-a (algae): 7.1 µg/L. Surface area: 242 acres.
Is Round 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 Round Lake?
- Round Lake typically sits around 60°F at the surface in October, from 380 EPA Water Quality Portal field readings (2012–2022). That is a typical value for the month, not a live reading.
How deep is Round Lake?
- No published bathymetric survey covers Round Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 32 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 242 acres.
Are there boat ramps on Round Lake?
- Round Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lakefront Park. Public access is listed as yes.
Can I fish at Round Lake?
- Round Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Illinois's fish and wildlife agency, so check its current regulations before you go.
Explore Round Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Species activity outlook by water temperature and season
Top lakes and where to stay in the Chain O'Lakes area
Where to stay at Illinois's top lakes, each with its readings
Illinois's cleanest lakes, ranked on agency measurements
More lakes in Illinois
Other Lakes in Illinois
Eutrophic Lakes in Illinois
Where this data comes from
42 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_WQX42 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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory