Lake Owyhee
Malheur County, OregonView mapDirections
Oregon DEQ publishes the water-quality measurements for Lake Owyhee. Here is what has been measured.
- Eutrophic
- Impaired · Mercury
- Public access
- Limited data
Lake Owyhee in Malheur County, Oregon has water-quality measurements published by Oregon DEQ, shown here as reported. Chlorophyll-a (algae): 15 µg/L.
Lake Owyhee is a productive, nutrient-rich eutrophic lake in Malheur County, Oregon. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 2 other monitored lakes in Malheur County, Lake Owyhee ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, Oregon DEQ, last sampled 2025-10-28. Methodology: how these readings are compared.
What Lake Owyhee is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Camping1 public campground nearby
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. Lake Owyhee is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, metals (other than mercury), pH / acidity, temperature, toxic inorganics. Check local advisories before you swim.
Whether Lake Owyhee 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 Lake Owyhee
These are the measurements Oregon DEQ publishes for Lake Owyhee, 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 15 µg/L. TSI 57.
| 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) | 15µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 57 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lake Owyhee
Answers come straight from the public measurements and survey records on this page.
Recreation & Access
- Leslie GulchPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Public campgrounds near Lake Owyhee
- Slocum Creek Campground0.6 km
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Lake Owyhee
Compare lakeside cabins, hotels, and vacation rentals near Lake Owyhee 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Lake Owyhee are listed below.
Top-rated places to stay near Lake Owyhee
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 Lake Owyhee → · more Oregon lake trips
Follow Lake Owyhee’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing Lake Owyhee
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
Worsening+6.5 µg/L/yr2 years
EPA Impairment Status
Lake Owyhee is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Drinking water, Aquatic life, Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit OR_LK_1705011006_05_100541 · Official waterbody report
Nearby Lakes in Malheur County
Frequently asked questions about Lake Owyhee
Where is Lake Owyhee?
- Lake Owyhee is a lake in Malheur County, Oregon. Its water-quality measurements are published by Oregon DEQ and shown on this page as reported.
What is the water quality of Lake Owyhee?
- Lake Owyhee in Malheur County, Oregon has water-quality measurements published by Oregon DEQ, shown here as reported. Chlorophyll-a (algae): 15 µg/L.
Is Lake Owyhee safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Owyhee is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, metals (other than mercury), pH / acidity, temperature, toxic inorganics. Check local advisories before you swim.
Are there boat ramps on Lake Owyhee?
- Lake Owyhee has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Leslie Gulch. Public access is listed as yes.
Can I fish at Lake Owyhee?
- Lake Owyhee has 1 documented boat landing 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.
Are there campgrounds on Lake Owyhee?
- Lake Owyhee has 1 public campground from USGS The National Map within 5 km, including Slocum Creek Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
Explore Lake Owyhee across LakeQuality
22.8 mi away · 55 ft
3.2 mi away · recorded at 106°F
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
More lakes in Oregon
Other Lakes in Oregon
Eutrophic Lakes in Oregon
Where this data comes from
7 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
OREGONDEQ7 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
Impairment status from EPA ATTAINS 303(d) database
Named boat-access points from the USGS National Boat Ramps inventory
Public campgrounds from USGS The National Map Structures, within about 3 miles