Lower Crystal Springs Reservoir
San Mateo County, California586 acresView mapDirections
No nutrient or algae sampling on record from SWRCB for this lake.
- Impaired · Mercury
- Limited data
Lower Crystal Springs Reservoir in San Mateo County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 586 acres.
Lower Crystal Springs Reservoir is a 586-acre lake in San Mateo County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Lower Crystal Springs Reservoir is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Lower Crystal Springs Reservoir 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 Lower Crystal Springs Reservoir
These are the measurements SWRCB publishes for Lower Crystal Springs Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data.
Ask about Lower Crystal Springs Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
586 acres
Shoreline
13.8 mi
No bathymetric survey has been published for Lower Crystal Springs Reservoir, so its depth is not documented here.
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Fishing Lower Crystal Springs Reservoir
EPA Impairment Status
Lower Crystal Springs Reservoir 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: Fish consumption, Other.
Source: EPA ATTAINS assessment unit CAL2044003220091208102149 · Official waterbody report
Nearby Lakes in San Mateo County
Frequently asked questions about Lower Crystal Springs Reservoir
Where is Lower Crystal Springs Reservoir?
- Lower Crystal Springs Reservoir is a lake in San Mateo County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Lower Crystal Springs Reservoir?
- Lower Crystal Springs Reservoir in San Mateo County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 586 acres.
Is Lower Crystal Springs Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lower Crystal Springs Reservoir is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
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Where this data comes from
Measurements for Lower Crystal Springs Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database