Skip to main content
LakeQuality

Western Boundary Lake

D
Grade D — Nutrient-rich
Nutrient-rich · #10 of 36 lakes in the county · 1.5 ft clear · Eutrophic
Eutrophic

Western Boundary Lake in Lake County, California has a water quality grade of D (Nutrient-rich). Water clarity: 1.5 ft visibility. Chlorophyll-a (algae): 13 µg/L.

Clarity
1.5 ft
Type
Eutrophic

Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Western Boundary Lake

Next lake in Lake County

Swipe

ARumsey Slough by the Old Bridge LakeLake CountyView →
Loading map…

Western Boundary Lake is a productive, nutrient-rich eutrophic lake in Lake County, California. Water quality is graded D based on 1 sampling years through 2026. Compared to the 35 other monitored lakes in Lake County, Western Boundary Lake ranks #10 for water quality.

Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2026-04-30. Grade methodology: LakeGrade methodology.

Watch Western Boundary Lake water quality

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Grade only

Elevated 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.

Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum

Get alerts for Western Boundary Lake

Water Quality Grade: D (Nutrient-rich)

Very murky, less than 1.5 ft of visibility. Chlorophyll-a: 13 µg/L. Trophic State Index: 64.

MetricValueGrade
Water Clarity (Secchi Depth)1.5 ftNot graded
PhosphorusNo recent samples
Chlorophyll-a (Algae)13 µg/LPoor
Trophic State Index (TSI)64Eutrophic

High nutrients, frequent algae, reduced clarity

Where to stay near Western Boundary Lake

Compare lakeside cabins, hotels, and vacation rentals near Western Boundary Lake in Lake County, California — 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 Western Boundary Lake are listed below.

Top-rated places to stay near Western Boundary Lake

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Fishing Western Boundary Lake

County Ranking

Ranked #10 of 36 lakes in Lake County

Nearby Lakes in Lake County

Frequently asked questions about Western Boundary Lake

Where is Western Boundary Lake?

Western Boundary Lake is a lake in Lake County, California. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.

What is the water quality grade for Western Boundary Lake?

Western Boundary Lake in Lake County, California has a water quality grade of D (Nutrient-rich). Water clarity: 1.5 ft visibility. Chlorophyll-a (algae): 13 µg/L.

Is Western Boundary Lake safe to swim in?

Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. Western Boundary Lake has a water quality grade of D (Nutrient-rich). Algae concentration (chlorophyll-a) is 13 µg/L. Always check local health department advisories before swimming.

Where this data comes from

160 measurements from 2 monitoring stations, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-21.

Collected and reported by

  • Big Valley Band of Pomo Indians of the Big Valley Rancheria, California (Tribal)CA_BVR160 samples · 2020–2026

Analytical methods

  • Chlorophyll a
Monitoring station identifiers (2)

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.