Fresno Reservoir
Hill County, Montana5,007 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
- Impaired · Habitat alterations
- 50 ft max depth
Fresno Reservoir in Hill County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Maximum depth: 50 ft. Surface area: 5007 acres.
Fresno Reservoir is a 5,007-acre lake in Hill County, Montana with a maximum depth of 50 feet.
Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.
What Fresno Reservoir is good for
From access and monitoring records, not editorial picks.
- Deep water50 ft surveyed max depth
- Big water5,007 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Fresno Reservoir is listed impaired under Clean Water Act §303(d) (IR 4C) for habitat alterations, hydrologic alteration. Check local advisories before you swim.
Whether Fresno Reservoir is safe to swim in today is a call for the Montana Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Fresno Reservoir
These are the measurements Montana DEQ publishes for Fresno Reservoir, 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 Fresno Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
50 ft
Surface area
5,007 acres
Shoreline
55.5 mi
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Fishing Fresno Reservoir
EPA Impairment Status
Fresno Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2021 EPA reporting cycle (IR category 4C).
Causes of impairment
Designated uses not supporting: Aquatic life.
Source: EPA ATTAINS assessment unit MT40F005_010 · Official waterbody report
Nearby Lakes in Hill County
Frequently asked questions about Fresno Reservoir
Where is Fresno Reservoir?
- Fresno Reservoir is a lake in Hill County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Fresno Reservoir?
- Fresno Reservoir in Hill County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Maximum depth: 50 ft. Surface area: 5007 acres.
Is Fresno Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Fresno Reservoir is listed impaired under Clean Water Act §303(d) (IR 4C) for habitat alterations, hydrologic alteration. Check local advisories before you swim.
How deep is Fresno Reservoir?
- Fresno Reservoir has a maximum depth of 50 feet. The lake covers 5007 acres.
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Where this data comes from
Measurements for Fresno Reservoir 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