Little Grassy Reservoir
Little Grassy Reservoir in Malheur County, Oregon is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 334 acres.
- Area
- 334 acres
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Why Little Grassy Reservoir 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 Little Grassy Reservoir, 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 Oregon DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Little Grassy Reservoir is a 334-acre lake in Malheur County, Oregon.
Source: EPA Water Quality Portal sampling records, Oregon DEQ, 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 Little Grassy Reservoir
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 Little Grassy Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Little Grassy Reservoir in Malheur County, Oregon — 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 Little Grassy Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 334 acres |
No bathymetric survey has been published for Little Grassy Reservoir, so its depth is not documented here.
Fishing Little Grassy Reservoir
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Frequently asked questions about Little Grassy Reservoir
Where is Little Grassy Reservoir?
- Little Grassy Reservoir is a lake in Malheur County, Oregon. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Little Grassy Reservoir?
- Little Grassy Reservoir in Malheur County, Oregon is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 334 acres.
Is Little Grassy Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Little Grassy Reservoir 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 Little Grassy Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.