Trillium Lake
Trillium Lake in Clackamas County, Oregon is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 58 acres.
- Area
- 58 acres
- Public access
- Yes
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Why Trillium 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 Trillium 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 Oregon DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Trillium Lake is a 58-acre lake in Clackamas County, Oregon. Limited fish-species data available. Public access is available with 1 public boat landing.
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 Trillium 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 Trillium Lake
Compare lakeside cabins, hotels, and vacation rentals near Trillium Lake in Clackamas 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 Trillium Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 58 acres |
| Public Access | Yes |
No bathymetric survey has been published for Trillium Lake, so its depth is not documented here.
Recreation & Access
- Trillium Lake CampPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Trillium Lake
Nearby Lakes in Clackamas County
Frequently asked questions about Trillium Lake
Where is Trillium Lake?
- Trillium Lake is a lake in Clackamas 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 Trillium Lake?
- Trillium Lake in Clackamas County, Oregon is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 58 acres.
Is Trillium Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Trillium Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Trillium Lake?
- Trillium Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Trillium Lake Camp. Public access is listed as yes.
Explore Trillium Lake across LakeQuality
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Where this data comes from
Measurements for Trillium Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Named boat-access points from the USGS National Boat Ramps inventory