Where is Lake Cassidy?

Lake Cassidy is a lake in Snohomish County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.

How deep is Lake Cassidy?

Lake Cassidy has a maximum depth of 20 feet and an average depth of 11 feet. The lake covers 123 acres.

Are there boat ramps on Lake Cassidy?

Lake Cassidy has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Cassidy. Public access is listed as yes.

Can I fish at Lake Cassidy?

Lake Cassidy 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 Washington's fish and wildlife agency, so check its current regulations before you go.

Lake Cassidy

Snohomish County, Washington123 acresView map Directions

No nutrient or algae sampling on record from Washington Ecology for this lake.

Max depth

20 ft

Bathymetric survey

Area

123 acres

Surface area

Shoreline

1.9 mi

Measured length

Impaired · Nutrients (phosphorus, nitrogen)
20 ft max depth
Public access

See the measurements Directions Where to stay

Lake Cassidy in Snohomish County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Maximum depth: 20 ft. Surface area: 123 acres.

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Lake Cassidy is a 123-acre lake in Snohomish County, Washington with a maximum depth of 20 feet (11-foot average). Limited fish-species data available. Public access is available with 1 public boat landing.

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

What Lake Cassidy is good for

From access and monitoring records, not editorial picks.

Boat launch1 documented ramp

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Lake Cassidy is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.

Whether Lake Cassidy is safe to swim in today is a call for the Washington State Department of Ecology and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Lake Cassidy

These are the measurements Washington Ecology publishes for Lake Cassidy, 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 Lake Cassidy

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

Lake Details

Max depth

20 ft

Average depth

11 ft

Surface area

123 acres

Shoreline

1.9 mi

Public access

Yes

Listed by Washington Ecology

Recreation & Access

Boat Landings

Yes

Public Access

Lake CassidyPublic

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

Stays via Stay22

Stays near Lake Cassidy

Compare lakeside cabins, hotels, and vacation rentals near Lake Cassidy in Snohomish County, Washington — 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 Lake Cassidy

Prices for Oct 16–18, 4 adults. Change dates on the map below.

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Follow Lake Cassidy’s readings

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Fishing Lake Cassidy

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

EPA Impairment Status

Lake Cassidy is officially listed as impaired under Clean Water Act §303(d) in the 2018 EPA reporting cycle (IR category 5).

Causes of impairment

Nutrients (phosphorus, nitrogen)

Designated uses not supporting: Aquatic life.

Source: EPA ATTAINS assessment unit WA17110011000443_001_001 · Official waterbody report

Nearby Lakes in Snohomish County

Lake Stevens3.6 miView →Blackmans Lake8.3 miView →Bosworth Lake5.7 miView →Panther Lake8.3 miView →Ross Lake6.7 miView →Flowing Lake8.7 miView →

Frequently asked questions about Lake Cassidy

Where is Lake Cassidy?: Lake Cassidy is a lake in Snohomish County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Lake Cassidy?: Lake Cassidy in Snohomish County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Maximum depth: 20 ft. Surface area: 123 acres.
Is Lake Cassidy safe to swim in?: Nutrient and algae readings are not a swimming clearance. Lake Cassidy is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
How deep is Lake Cassidy?: Lake Cassidy has a maximum depth of 20 feet and an average depth of 11 feet. The lake covers 123 acres.
Are there boat ramps on Lake Cassidy?: Lake Cassidy has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Cassidy. Public access is listed as yes.
Can I fish at Lake Cassidy?: Lake Cassidy 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 Washington's fish and wildlife agency, so check its current regulations before you go.