Lake Combie
Lake Combie in Nevada County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 360 acres.
- Area
- 360 acres
Why Lake Combie has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Lake Combie, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by your state environmental agency and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lake Combie is a 360-acre lake in Nevada County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2021-06-15. Grade methodology: LakeGrade methodology.
Watch Lake Combie water quality
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lake Combie
These readings exist but do not meet the evidence bar for an A–F grade — see why.
No clarity data.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples |
Where to stay near Lake Combie
Compare lakeside cabins, hotels, and vacation rentals near Lake Combie in Nevada 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.
Top-rated places to stay near Lake Combie
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 360 acres |
No bathymetric survey has been published for Lake Combie, so its depth is not documented here.
Fishing Lake Combie
Reservoir Info (USACE NID)
Lake Combie is a man-made reservoir impounded by the Lake Combie (completed 1928), built primarily for irrigation on the Bear River; concrete-type dam, 100 ft tall and 762 ft long.
- Surface area
- 360 ac
- Normal storage
- 5,555 ac-ft
- Drainage area
- 135.6 sq mi
- Hazard class
- High
- Owner
- Nevada Irrigation District
All listed purposes: Irrigation;Hydroelectric;Water Supply.
Source: USACE National Inventory of Dams, NID ID CA00249 · Operator website
EPA Impairment Status
Lake Combie is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit CAL5163301120020111100904 · Official waterbody report
Nearby Lakes in Nevada County
Frequently asked questions about Lake Combie
Where is Lake Combie?
- Lake Combie is a lake in Nevada County, California. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Lake Combie?
- Lake Combie in Nevada County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 360 acres.
Is Lake Combie safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Combie is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Lake Combie across LakeGrade
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Where this data comes from
9 measurements from 1 monitoring station, 2020–2021. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- USGS California Water Science Center
USGS-CA9 samples · 2020–2021
Analytical methods
- YSI EXO turbidity sensor, FNU
- YSI Environmental, sensor 6136
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