Upper Mystic Lake
Middlesex County, Massachusetts176 acresView mapDirections
No nutrient or algae sampling on record from MassDEP for this lake.
- Impaired · Algal growth
- 89 ft max depth
Upper Mystic Lake in Middlesex County, Massachusetts has water-quality measurements published by MassDEP, shown here as reported. Maximum depth: 88.6 ft. Surface area: 176 acres.
Upper Mystic Lake is a 176-acre lake in Middlesex County, Massachusetts with a maximum depth of 89 feet.
Source: EPA Water Quality Portal sampling records, MassDEP. Methodology: how these readings are compared.
What Upper Mystic Lake is good for
From access and monitoring records, not editorial picks.
- Deep water88.6 ft surveyed max depth
Swimming conditions
No readingBacteria advisory
Nutrient and algae readings are not a swimming clearance. Upper Mystic Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, nutrients (phosphorus, nitrogen), oxygen depletion (low DO), pathogens (E. coli, fecal). Check local advisories before you swim.
Whether Upper Mystic Lake is safe to swim in today is a call for the Massachusetts Department of Environmental Protection and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Upper Mystic Lake
These are the measurements MassDEP publishes for Upper Mystic 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 Upper Mystic Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
88.6 ft
Surface area
176 acres
Shoreline
3.7 mi
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Fishing Upper Mystic Lake
EPA Impairment Status
Upper Mystic Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Aquatic life, Recreation.
Source: EPA ATTAINS assessment unit MA71043 · Official waterbody report
Nearby Lakes in Middlesex County
Frequently asked questions about Upper Mystic Lake
Where is Upper Mystic Lake?
- Upper Mystic Lake is a lake in Middlesex County, Massachusetts. Its water-quality measurements are published by MassDEP and shown on this page as reported.
What is the water quality of Upper Mystic Lake?
- Upper Mystic Lake in Middlesex County, Massachusetts has water-quality measurements published by MassDEP, shown here as reported. Maximum depth: 88.6 ft. Surface area: 176 acres.
Is Upper Mystic Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Upper Mystic Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, nutrients (phosphorus, nitrogen), oxygen depletion (low DO), pathogens (E. coli, fecal). Check local advisories before you swim.
How deep is Upper Mystic Lake?
- Upper Mystic Lake has a maximum depth of 88.6 feet. The lake covers 176 acres.
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Where this data comes from
Measurements for Upper Mystic Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database