Where is Mallard Reservoir?

Mallard Reservoir is a lake in Contra Costa County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.

Mallard Reservoir

Contra Costa County, California203 acresView map Directions

No nutrient or algae sampling on record from SWRCB for this lake.

Area

203 acres

Surface area

Shoreline

2.5 mi

Measured length

See the measurements Directions Where to stay

Mallard Reservoir in Contra Costa County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 203 acres.

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Mallard Reservoir is a 203-acre lake in Contra Costa County, California.

Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Mallard 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.

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Water quality measurements for Mallard Reservoir

These are the measurements SWRCB publishes for Mallard 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. TSI undefined.

Ask about Mallard Reservoir

Answers come straight from the public measurements and survey records on this page.

Lake Details

Surface area

203 acres

Shoreline

2.5 mi

No bathymetric survey has been published for Mallard Reservoir, so its depth is not documented here.

Stays via Stay22

Stays near Mallard Reservoir

Compare lakeside cabins, hotels, and vacation rentals near Mallard Reservoir in Contra Costa 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 Mallard Reservoir

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Fishing Mallard Reservoir

→ Mallard Reservoir fishing regulations (limits, seasons, special rules)

Nearby Lakes in Contra Costa County

Lafayette Reservoir10.8 miView →Briones Reservoir10.1 miView →Contra Loma Reservoir4.1 ft clear12.1 miView →San Pablo Reservoir12.7 miView →Antioch Municipal Reservoir13 miView →Lake Anza12.3 ft clear—View →

Frequently asked questions about Mallard Reservoir

Where is Mallard Reservoir?: Mallard Reservoir is a lake in Contra Costa County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Mallard Reservoir?: Mallard Reservoir in Contra Costa County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 203 acres.
Is Mallard Reservoir safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.