Big Bear Lake
San Bernardino County, CaliforniaView mapDirections
SWRCB publishes the water-quality measurements for Big Bear Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Biotoxins
- Limited data
Big Bear Lake in San Bernardino County, California has water-quality measurements published by SWRCB, shown here as reported. Phosphorus: 50 µg/L.
Big Bear Lake is a highly nutrient-loaded hypereutrophic lake in San Bernardino County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2021-07-27. Methodology: how these readings are compared.
What Big Bear Lake is good for
From access and monitoring records, not editorial picks.
- Camping1 public campground nearby
Swimming conditions
Readings onlyBacteria advisory
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. Big Bear Lake is listed impaired under Clean Water Act §303(d) (IR 5) for biotoxins, mercury, pesticides, pCBs. Check local advisories before you swim.
Whether Big Bear Lake is safe to swim in today is a call for the California State Water Resources Control Board and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Big Bear Lake
These are the measurements SWRCB publishes for Big Bear 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. Phosphorus 50 µg/L. TSI 71.
| 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 | 50µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 71 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Big Bear Lake
Answers come straight from the public measurements and survey records on this page.
Recreation & Access
Public campgrounds near Big Bear Lake
- Serrano Cg1.1 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 Big Bear Lake
Compare lakeside cabins, hotels, and vacation rentals near Big Bear Lake in San Bernardino 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 readings cover nutrients and algae, not lodging. Cabins and rentals around Big Bear Lake are listed below.
Top-rated places to stay near Big Bear Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Fishing Big Bear Lake
EPA Impairment Status
Big Bear Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Drinking water, Aquatic life, Fish consumption, Recreation, Other.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit CAL8017100019990208151909 · Official waterbody report
Nearby Lakes in San Bernardino County
Frequently asked questions about Big Bear Lake
Where is Big Bear Lake?
- Big Bear Lake is a lake in San Bernardino County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Big Bear Lake?
- Big Bear Lake in San Bernardino County, California has water-quality measurements published by SWRCB, shown here as reported. Phosphorus: 50 µg/L.
Is Big Bear Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Big Bear Lake is listed impaired under Clean Water Act §303(d) (IR 5) for biotoxins, mercury, pesticides, pCBs. Check local advisories before you swim.
Are there campgrounds on Big Bear Lake?
- Big Bear Lake has 1 public campground from USGS The National Map within 5 km, including Serrano Cg. 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.
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Where this data comes from
2 measurements from 2 monitoring stations, 2021. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- California State Water Resources Control Board
CEDEN2 samples · 2021
Analytical methods
- SM 4500-P BE
Monitoring station identifiers (2)
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
Public campgrounds from USGS The National Map Structures, within about 3 miles