Ish Reservoir
Boulder County, Colorado317 acresView mapDirections
No nutrient or algae sampling on record from Colorado WQCD for this lake.
Ish Reservoir in Boulder County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Surface area: 317 acres.
Ish Reservoir is a 317-acre lake in Boulder County, Colorado.
Source: EPA Water Quality Portal sampling records, CDPHE. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Ish 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 Ish Reservoir
These are the measurements Colorado WQCD publishes for Ish 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 Ish Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
317 acres
Shoreline
3.6 mi
No bathymetric survey has been published for Ish Reservoir, so its depth is not documented here.
Stays via Stay22
Stays near Ish Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Ish Reservoir in Boulder County, Colorado — 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.
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Frequently asked questions about Ish Reservoir
Where is Ish Reservoir?
- Ish 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 Ish Reservoir?
- Ish Reservoir in Boulder County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Surface area: 317 acres.
Is Ish Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Ish Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.