Where is Crystal Lake?

Crystal Lake is a lake in McHenry County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.

How deep is Crystal Lake?

Crystal Lake has a maximum depth of 46 feet and an average depth of 13.4 feet. The lake covers 230 acres.

Are there boat ramps on Crystal Lake?

Crystal Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lakeshore Drive.

Can I fish at Crystal Lake?

Crystal 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.

Crystal Lake

McHenry County, Illinois230 acresView map Directions

No nutrient or algae sampling on record from Illinois EPA for this lake.

Max depth

46 ft

Bathymetric survey

Area

230 acres

Surface area

Shoreline

3.2 mi

Measured length

46 ft max depth

See the measurements Directions Where to stay

Crystal Lake in McHenry County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Maximum depth: 46 ft. Surface area: 230 acres.

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Crystal Lake is a 230-acre lake in McHenry County, Illinois with a maximum depth of 46 feet (13-foot average). Public access is available with 1 public boat landing.

Source: EPA Water Quality Portal sampling records, Illinois EPA. Methodology: how these readings are compared.

What Crystal Lake is good for

From access and monitoring records, not editorial picks.

Boat launch1 documented ramp
Deep water46 ft surveyed max depth

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Crystal 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.

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Water quality measurements for Crystal Lake

These are the measurements Illinois EPA publishes for Crystal Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

No clarity data. TSI undefined.

Ask about Crystal Lake

Answers come straight from the public measurements and survey records on this page.

Lake Details

Max depth

46 ft

Average depth

13.4 ft

Surface area

230 acres

Shoreline

3.2 mi

Recreation & Access

Boat Landings

Lakeshore DriveSemi-private

Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps

Stays via Stay22

Stays near Crystal Lake

Compare lakeside cabins, hotels, and vacation rentals near Crystal Lake in McHenry 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 Crystal Lake

Prices for Oct 16–18, 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.

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Follow Crystal Lake’s readings

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Fishing Crystal Lake

→ Crystal Lake fishing regulations (limits, seasons, special rules)

Nearby Lakes in McHenry County

Vulcan Lakes2.9 miView →Woods Creek Lake3.9 ft clear · Eutrophic3.9 miView →Lake in the Hills4 miView →Lake Killarney5 miView →Wold Lake6.9 miView →Silver Lake7 ft clear · Mesotrophic5.5 miView →

Frequently asked questions about Crystal Lake

Where is Crystal Lake?: Crystal Lake is a lake in McHenry County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Crystal Lake?: Crystal Lake in McHenry County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Maximum depth: 46 ft. Surface area: 230 acres.
Is Crystal Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Crystal Lake?: Crystal Lake has a maximum depth of 46 feet and an average depth of 13.4 feet. The lake covers 230 acres.
Are there boat ramps on Crystal Lake?: Crystal Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lakeshore Drive.
Can I fish at Crystal Lake?: Crystal 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.