Rumsey Slough Mid Lake
Rumsey Slough Mid Lake in Lake County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Chlorophyll-a (algae): 4.6 µg/L.
Why Rumsey Slough Mid Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: 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 Rumsey Slough Mid Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded algae (chlorophyll-a), but not water clarity and phosphorus.
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.
Rumsey Slough Mid Lake is a lake in Lake County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2026-04-30. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Rumsey Slough Mid Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
No clarity data. Chlorophyll-a: 4.6 µg/L. Trophic State Index: 46.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | 4.6 µg/L | Not graded |
| Trophic State Index (TSI) | 46 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Rumsey Slough Mid Lake
Compare lakeside cabins, hotels, and vacation rentals near Rumsey Slough Mid Lake in Lake 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 Rumsey Slough Mid Lake
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Fishing Rumsey Slough Mid Lake
Graded lakes near Rumsey Slough Mid Lake
Rumsey Slough Mid Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Lake County
Frequently asked questions about Rumsey Slough Mid Lake
Where is Rumsey Slough Mid Lake?
- Rumsey Slough Mid Lake is a lake in Lake County, California. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Rumsey Slough Mid Lake?
- Rumsey Slough Mid Lake in Lake County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Chlorophyll-a (algae): 4.6 µg/L.
Is Rumsey Slough Mid Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Rumsey Slough Mid Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Algae concentration (chlorophyll-a) is 4.6 µg/L. Always check local health department advisories before swimming.
Explore Rumsey Slough Mid Lake across LakeGrade
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Other Lakes in California
Mesotrophic Lakes in California
Where this data comes from
37 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- Big Valley Band of Pomo Indians of the Big Valley Rancheria, California (Tribal)
CA_BVR37 samples · 2020–2026
Analytical methods
- Chlorophyll a
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.