Gross Reservoir
Boulder County, Colorado415 acresView mapDirections
No nutrient or algae sampling on record from Colorado WQCD for this lake.
- 299 ft max depth
Gross Reservoir in Boulder County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Maximum depth: 298.6 ft. Surface area: 415 acres.
Gross Reservoir is a 415-acre lake in Boulder County, Colorado with a maximum depth of 299 feet.
Source: EPA Water Quality Portal sampling records, CDPHE. Methodology: how these readings are compared.
What Gross Reservoir is good for
From access and monitoring records, not editorial picks.
- Deep water298.6 ft surveyed max depth
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Gross Reservoir is safe to swim in today is a call for the Water Quality Control Division of the Colorado Department of Public Health and Environment and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Gross Reservoir
These are the measurements Colorado WQCD publishes for Gross 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 Gross Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
298.6 ft
Surface area
415 acres
Shoreline
10.6 mi
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Fishing Gross Reservoir
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Frequently asked questions about Gross Reservoir
Where is Gross Reservoir?
- Gross Reservoir is a lake in Boulder County, Colorado. Its water-quality measurements are published by Colorado WQCD and shown on this page as reported.
What is the water quality of Gross Reservoir?
- Gross Reservoir in Boulder County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Maximum depth: 298.6 ft. Surface area: 415 acres.
Is Gross Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Gross Reservoir?
- Gross Reservoir has a maximum depth of 298.6 feet. The lake covers 415 acres.
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Where this data comes from
Measurements for Gross Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.