Merlo Lake
Merlo Lake in Sonoma County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 44 acres.
- Area
- 44 acres
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Why Merlo Lake 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 Merlo Lake, 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 your state environmental agency and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Merlo Lake is a 44-acre lake in Sonoma County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency, 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 Merlo Lake
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 Merlo Lake
Compare lakeside cabins, hotels, and vacation rentals near Merlo Lake in Sonoma County, California — 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 Merlo Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 44 acres |
No bathymetric survey has been published for Merlo Lake, so its depth is not documented here.
Fishing Merlo Lake
Nearby Lakes in Sonoma County
Frequently asked questions about Merlo Lake
Where is Merlo Lake?
- Merlo Lake is a lake in Sonoma County, California. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Merlo Lake?
- Merlo Lake in Sonoma County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 44 acres.
Is Merlo Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Merlo Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Merlo Lake across LakeQuality
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Where this data comes from
Measurements for Merlo Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.