Green Peter Lake
Linn County, Oregon3,720 acresView mapDirections
Oregon DEQ publishes the water-quality measurements for Green Peter Lake. Here is what has been measured.
- Oligotrophic
- 51 ft max depth
- Public access
- Limited data
Green Peter Lake in Linn County, Oregon has water-quality measurements published by Oregon DEQ, shown here as reported. Chlorophyll-a (algae): 1.4 µg/L. Surface area: 3720 acres.
Green Peter Lake is a 3,720-acre cold, clear oligotrophic lake in Linn County, Oregon with an estimated average depth of about 51 feet. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available with 3 public boat landings. Compared to the 1 other monitored lakes in Linn County, Green Peter Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Oregon DEQ, last sampled 2025-08-06. Methodology: how these readings are compared.
Green Peter Lake covers about 3,700 acres in Linn County. It has 3 public boat landings, so a lakefront rental is not the only way to get a boat on the water. If you are planning to stay, you can search lake houses and cabins around Green Peter Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Green Peter Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch3 documented ramps
- Big water3,720 acres
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Green Peter Lake is safe to swim in today is a call for the Oregon Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Green Peter Lake
These are the measurements Oregon DEQ publishes for Green Peter Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Chlorophyll-a 1.4 µg/L. TSI 34.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | 1.4µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 34 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Green Peter Lake
Answers come straight from the public measurements and survey records on this page.
→ Green Peter Lake water level: the live USGS gauge reading
Lake Details
Max depth
~51 ft est.
Surface area
3,720 acres
Public access
Yes
Listed by Oregon DEQ
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Oregon has not published bathymetry for Green Peter Lake.
Lake Size & Watershed
Watershed (drainage) area
278 sq mi
HydroLAKES / HydroSHEDS
Shoreline
31.2 mi
HydroLAKES / HydroSHEDS
Elevation
955 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Recreation & Access
- Whitcomb Creek County ParkPublic
- Thistle CreekPublic
- Billings ParkPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Green Peter Lake
Compare lakeside cabins, hotels, and vacation rentals near Green Peter Lake in Linn 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 Green Peter Lake
Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a trip? Cabins and lodging at Green Peter Lake → · more Oregon lake trips
Follow Green Peter Lake’s readings
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Fishing Green Peter Lake
Water quality readings over time
2 seasons of samples on record (2024–2025). Calling a direction takes at least 4 years of the same measurement.
Chlorophyll-a
Improving-0.9 µg/L/yr2 years
Reservoir Info (USACE NID)
Green Peter Lake is a man-made reservoir impounded by the Green Peter Dam (completed 1967), built primarily for flood risk reduction on the Middle Santiam River; gravity-type dam, 378 ft tall and 1,517 ft long.
- Surface area
- 3,720 ac
- Normal storage
- 160,000 ac-ft
- Max storage
- 430,000 ac-ft
- Drainage area
- 277 sq mi
- Hazard class
- High
- Owner
- USACE - Portland District
All listed purposes: Flood Risk Reduction;Other;Irrigation;Navigation;Recreation;Hydroelectric.
Source: USACE National Inventory of Dams, NID ID OR00010 · Operator website
Nearby Lakes in Linn County
Frequently asked questions about Green Peter Lake
Where is Green Peter Lake?
- Green Peter Lake is a lake in Linn County, Oregon. Its water-quality measurements are published by Oregon DEQ and shown on this page as reported.
What is the water quality of Green Peter Lake?
- Green Peter Lake in Linn County, Oregon has water-quality measurements published by Oregon DEQ, shown here as reported. Chlorophyll-a (algae): 1.4 µg/L. Surface area: 3720 acres.
Is Green Peter Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Green Peter Lake?
- No published bathymetric survey covers Green Peter Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 51 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 3720 acres.
Are there boat ramps on Green Peter Lake?
- Green Peter Lake has 3 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Whitcomb Creek County Park, Thistle Creek, Billings Park. Public access is listed as yes.
Can I fish at Green Peter Lake?
- Green Peter Lake has 3 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Oregon's fish and wildlife agency, so check its current regulations before you go.
Explore Green Peter Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Species activity outlook by water temperature and season
Where to stay at Oregon's top lakes, each with its readings
Oregon's cleanest lakes, ranked on agency measurements
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Where this data comes from
6 measurements from 1 monitoring station, 2024–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Department of Environmental Quality - State of Oregon
OREGONDEQ6 samples · 2024–2025
Analytical methods
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory