Keswick Reservoir
Keswick Reservoir in Shasta County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 640 acres.
- Area
- 640 acres
- Public access
- Yes
Why Keswick Reservoir 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 Keswick Reservoir, 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.
Keswick Reservoir is a 640-acre lake in Shasta County, California. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2022-04-10. Grade methodology: LakeGrade methodology.
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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 Keswick Reservoir
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 Keswick Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Keswick Reservoir in Shasta 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 Keswick Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 640 acres |
| Public Access | Yes |
No bathymetric survey has been published for Keswick Reservoir, so its depth is not documented here.
Recreation & Access
- Keswick BoatPublic
Named access points from the USGS National Boat Ramps inventory, snapped within 5 km. More lakes with boat ramps
Fishing Keswick Reservoir
Reservoir Info (USACE NID)
Keswick Reservoir is a man-made reservoir impounded by the Keswick Dam (completed 1950), built primarily for flood risk reduction on the Sacramento River; concrete-type dam, 157 ft tall and 1,046 ft long.
- Surface area
- 640 ac
- Normal storage
- 7,470 ac-ft
- Max storage
- 25,132 ac-ft
- Drainage area
- 6,032.87 sq mi
- Hazard class
- High
- Owner
- BUREAU OF RECLAMATION
All listed purposes: Flood Risk Reduction;Irrigation;Hydroelectric.
Source: USACE National Inventory of Dams, NID ID CA10160 · Operator website
EPA Impairment Status
Keswick Reservoir 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 CAL5244001220020730101915 · Official waterbody report · Matched by proximity (1.21 km)
Nearby Lakes in Shasta County
Frequently asked questions about Keswick Reservoir
Where is Keswick Reservoir?
- Keswick Reservoir is a lake in Shasta 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 Keswick Reservoir?
- Keswick Reservoir in Shasta County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 640 acres.
Is Keswick Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Keswick Reservoir is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Keswick Reservoir?
- Keswick Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Keswick Boat. Public access is listed as yes.
Explore Keswick Reservoir across LakeGrade
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Where this data comes from
3 measurements from 3 monitoring stations, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- USGS California Water Science Center
USGS-CA3 samples · 2022
Analytical methods
- YSI Environmental, sensor 6136
Monitoring station identifiers (3)
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
Named boat-access points from the USGS National Boat Ramps inventory