Lake
Thurston County, WashingtonView mapDirections
Nutrients and algae run above the regional average.
↓ down from B at the last regrade
- Eutrophic
- Impaired · Mercury
- #15 of 16 in the county
- 23 ft max depth
- Public access
Lake in Thurston County, Washington has a water quality grade of D (Nutrient-rich). Phosphorus: 26 µg/L. Chlorophyll-a (algae): 7.2 µg/L.
- Max depth
- ~23 ft est.
- Type
- Eutrophic
- Phosphorus
- 26 µg/L
- Chlorophyll-a
- 7.2 µg/L
- Trend
- ↑ Improving
- Public access
- Yes
Stays via Stay22
Stays near Lake
Compare lakeside cabins, hotels, and vacation rentals near Lake in Thurston County, Washington — 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 grade measures nutrients and algae, not lodging — cabins and rentals around Lake are listed below.
Top-rated places to stay near Lake
Prices for Sep 11–13, 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 → · more Washington lake trips
Watch Lake’s letter
Email me if this lake’s grade moves. Grades stay free.
Or email
Lake is a productive, nutrient-rich eutrophic lake in Thurston County, Washington with an estimated average depth of about 23 feet. Water quality is graded D based on 3 sampling years through 2025. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 15 other monitored lakes in Thurston County, Lake ranks #15 for water quality.
Source: EPA Water Quality Portal sampling records, WA Ecology, last sampled 2025-10-22. Grade methodology: LakeQuality methodology.
What Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming Safety
Grade onlyElevated nutrients
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The D is nutrients and algae, not a swimming clearance. Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Water Quality Grade: D (Nutrient-rich)
No clarity data. Phosphorus 26 µg/L. Chlorophyll-a 7.2 µg/L. TSI 51. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 26 µg/L | Fair |
| Chlorophyll-a (Algae) | 7.2 µg/L | Poor |
| Trophic State Index (TSI) | 51 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~23 ft est. |
| Average Depth | ~15 ft est. |
| Public Access | Yes |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Washington has not published bathymetry for Lake.
Lake Size & Watershed
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
- Offutt LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Lake
Water Quality Trend: ↑ Improving
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Phosphorus | ↑ Improving | -16.46 µg/L/yr | 3 |
| Chlorophyll-a | ↑ Improving | -0.29 µg/L/yr | 4 |
EPA Impairment Status
Lake is officially listed as impaired under Clean Water Act §303(d) in the 2018 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit WA17110016000114_001_001 · Official waterbody report
County Ranking
Ranked #15 of 16 lakes in Thurston County
Nearby Lakes With Higher Grades
Lake holds Grade D. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Thurston County
Frequently asked questions about Lake
Where is Lake?
- Lake is a lake in Thurston County, Washington. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Lake?
- Lake in Thurston County, Washington has a water quality grade of D (Nutrient-rich). Phosphorus: 26 µg/L. Chlorophyll-a (algae): 7.2 µg/L.
Is Lake safe to swim in?
- The D is nutrients and algae, not a swimming clearance. Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
How deep is Lake?
- No published bathymetric survey covers Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 23 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Are there boat ramps on Lake?
- Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Offutt Lake. Public access is listed as yes.
Explore Lake across LakeQuality
Species activity outlook by water temperature and season
Where to stay at Washington's top lakes, each with its grade
High nutrients, frequent algae, reduced clarity
Washington's cleanest and most-polluted lakes, ranked
More Washington Lake Rankings
Eutrophic Lakes in Washington
Where this data comes from
49 measurements from 1 monitoring station, 2019–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Thurston County Health Department
THURSTONCOUNTY49 samples · 2019–2025
Analytical methods
- External files contain methodological data
- Total Nitrogen, calculated (TKN + Nitrate/Nitrite)
- Phosphorus/Orthophosphate by Automated Ascorbic Acid Reduction Method
- Fluorometric determination of chlorophyll a in presence of pheophytin
- Nitrogen, Persulfate Method
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.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory