Lake Isabelle
Lake Isabelle in Boulder County, Colorado is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 31 acres.
- Area
- 31 acres
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Why Lake Isabelle has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Lake Isabelle, no water-quality sampling on record for this lake.
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by CDPHE and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lake Isabelle is a 31-acre lake in Boulder County, Colorado.
Source: EPA Water Quality Portal sampling records, CDPHE, last sampled recent years. Grade methodology: LakeQuality methodology.
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Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lake Isabelle
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Lake Isabelle
Compare lakeside cabins, hotels, and vacation rentals near Lake Isabelle 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.
Top-rated places to stay near Lake Isabelle
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 31 acres |
No bathymetric survey has been published for Lake Isabelle, so its depth is not documented here.
Fishing Lake Isabelle
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Frequently asked questions about Lake Isabelle
Where is Lake Isabelle?
- Lake Isabelle is a lake in Boulder County, Colorado. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Lake Isabelle?
- Lake Isabelle in Boulder County, Colorado is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 31 acres.
Is Lake Isabelle safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Isabelle is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
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Where this data comes from
Measurements for Lake Isabelle come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.