Water Quality in Sonora, CA (95370)
EPA violation data for public water systems serving ZIP code 95370.
Active Health Violations
5 health-based violations found in the past 5 years, with at least one still unresolved. Contaminant levels have exceeded federal safety limits. Consider testing your tap water independently.
More violations than 80% of US ZIP codes.
Based on EPA compliance data. Not a substitute for an official water quality report from your utility.
28,355
Population
136
Water Systems
27
Violations (5yr)
5
Health-Based
Location
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Water Systems Serving This Area (136)
Tud - Upper Basin Water System
Surface water 13,280 people served
0 violations
Tud - Sonora/Jamestown Water System
All resolved Surface water 11,054 people served
1 violation (5yr)
· All resolved
Lead tested: 8.1 ppb (limit: 15 ppb) ✓
Tud - Columbia Water System
Surface water 5,463 people served
0 violations
Tud - Crystal Falls Water System
Surface water 5,393 people served
0 violations
Peppery Bar And Grill, The
Groundwater 4,500 people served
0 violations
Tud - Cedar Ridge Water System
Surface water 1,879 people served
0 violations
Lead tested: 0 ppb (limit: 15 ppb) ✓
Tud - Ponderosa
All resolved Surface water 1,767 people served
1 violation (5yr)
· All resolved
Lead tested: 0 ppb (limit: 15 ppb) ✓
Tud - Tuolumne Water System
All resolved Surface water 1,761 people served
1 violation (5yr)
· All resolved
Lead tested: 0 ppb (limit: 15 ppb) ✓
Phoenix Lake Estates Cc Mwc
Groundwater 1,168 people served
0 violations
Lead tested: 0 ppb (limit: 15 ppb) ✓
Sonora Meadows Mutual Wtr Co
1 health-based Purchased surface water 1,123 people served
2 violations (5yr)
· 1 health-based
Lead tested: 0 ppb (limit: 15 ppb) ✓
Usbr-Tuttletown Rec Area
Groundwater 1,000 people served
0 violations
Tud-Apple Valley Estates
Groundwater 826 people served
0 violations
Tud - Mono Village Water System
Surface water 640 people served
0 violations
Tud - Monte Grande Water System
Surface water 548 people served
0 violations
Tud-Cuesta Center-Lambert Lakes
Purchased surface water 533 people served
0 violations
Tud - Big Hill Water System
Surface water 531 people served
0 violations
Belleview Oaks Mutual Water Co
All resolved Groundwater 468 people served
1 violation (5yr)
· All resolved
Slide Inn Snowbowl Water Co
All resolved Groundwater 417 people served
1 violation (5yr)
· All resolved
Lead tested: 3.34 ppb (limit: 15 ppb) ✓
Scenic Brook Estates Mwc
Groundwater 400 people served
0 violations
Big Meadows Campground
Groundwater 390 people served
0 violations
Usfs Baker/Deadman Cgd
All resolved Groundwater 366 people served
1 violation (5yr)
· All resolved
Usfs Pinecrest Rec Area
Surface water 361 people served
0 violations
A.C. Still
Surface water 350 people served
0 violations
Baker & Deadman
Surface water 335 people served
0 violations
Usfs Sourgrass Campgd
Groundwater 300 people served
0 violations
Sierra Outdoor School
All resolved Groundwater 289 people served
1 violation (5yr)
· All resolved
Tud-East Sonora Water System
Purchased surface water 269 people served
0 violations
Dean Turner
Groundwater 250 people served
0 violations
Tuolumne River Resort
Groundwater 250 people served
0 violations
Sand Flat Campground
Groundwater 240 people served
0 violations
Foothill Horizons
Groundwater 230 people served
0 violations
Old Oak Ranch
Surface water 217 people served
0 violations
Rancho Poquitos Mwc
Groundwater 211 people served
0 violations
Atlas Business Park
All resolved Groundwater 210 people served
1 violation (5yr)
· All resolved
Lead tested: 0 ppb (limit: 15 ppb) ✓
Mother Lode Mobile Estates
All resolved Groundwater 210 people served
1 violation (5yr)
· All resolved
Tuolumne Regional Water Dist.
Surface water 175 people served
0 violations
Wm. & Frances Brewer
Groundwater 157 people served
0 violations
Tud - Phoenix Lake Park
Groundwater 157 people served
0 violations
Firefall Ranch Water System
1 health-based Groundwater 126 people served
3 violations (5yr)
· 1 health-based
Lead tested: 0 ppb (limit: 15 ppb) ✓
A.C. Still
Surface water 119 people served
0 violations
Usfs Utica Union Campground
Groundwater 108 people served
0 violations
Usfs Hull Creek Campgd
All resolved Groundwater 100 people served
1 violation (5yr)
· All resolved
Glory Hole Recreation Area
Groundwater 100 people served
0 violations
Usbr-Admin Center
Groundwater 100 people served
0 violations
Usfs Groveland Ranger Stn.
All resolved Groundwater 100 people served
1 violation (5yr)
· All resolved
Stanislaus River Campground
Groundwater 100 people served
0 violations
Kennedy Meadows Resort
All resolved Groundwater 100 people served
1 violation (5yr)
· All resolved
Angels Arm Water Plant
Surface water 100 people served
0 violations
Belleview Elementary School
Groundwater 96 people served
0 violations
Tud-Peaceful Pines Water System
Groundwater 92 people served
0 violations
Sno Bowl Water Co
Groundwater 91 people served
0 violations
Leland Creek-Water System
Surface water 91 people served
0 violations
Sierra Village
Purchased groundwater 91 people served
0 violations
Usfs Boulder Flat
Groundwater 80 people served
0 violations
Usfs Sweetwater Campground
Groundwater 78 people served
0 violations
Phoenix Lake Golf Club
Groundwater 64 people served
0 violations
Tud-Wards Ferry Ranches
All resolved Groundwater 62 people served
1 violation (5yr)
· All resolved
Lead tested: 0 ppb (limit: 15 ppb) ✓
Usfs Beardsley Picnic Ground
Groundwater 60 people served
0 violations
Sonora East Center
All resolved Groundwater 60 people served
1 violation (5yr)
· All resolved
Gus S Steakhouse
Groundwater 60 people served
0 violations
Usfs Lost Claim
1 health-based Groundwater 60 people served
1 violation (5yr)
· 1 health-based · All resolved
Hull Creek Campground
Groundwater 55 people served
0 violations
Mountain View Motel
Surface water 54 people served
0 violations
Ponderosa Mobile Home Park
1 health-based Groundwater 52 people served
3 violations (5yr)
· 1 health-based
Lead tested: 0 ppb (limit: 15 ppb) ✓
Usfs Cherry Valley Campgd
1 health-based Groundwater 51 people served
1 violation (5yr)
· 1 health-based · All resolved
Pinocchio'S
Surface water 50 people served
0 violations
Terraced Mobile Home Park
Groundwater 50 people served
0 violations
Standard Park Water System
Groundwater 50 people served
0 violations
Teleli Golf Club
Groundwater 50 people served
0 violations
Pacific Valley Campground
Groundwater 50 people served
0 violations
Usfs Black Oak Campground
Groundwater 44 people served
0 violations
Henry W. Ruoff
Groundwater 40 people served
0 violations
Sidney Hatler
Surface water 40 people served
0 violations
Apple Valley Farms
All resolved Groundwater 40 people served
1 violation (5yr)
· All resolved
J.D. Morrison, Owner
Surface water 34 people served
0 violations
Usfs Beardsley Campground
Groundwater 32 people served
0 violations
Oak Ridge Ranch
Groundwater 30 people served
0 violations
E. Ramsey, Owner
Purchased surface water 30 people served
0 violations
Don Lydick
Groundwater 30 people served
0 violations
Rube'S Pancake House
Groundwater 30 people served
0 violations
Terrible Herbst Oil Company
Groundwater 28 people served
0 violations
Underwood Acres Mwc
Groundwater 27 people served
0 violations
Nature Whole Food Depot
Groundwater 26 people served
0 violations
Usfs Sandbar Flat Campgd
All resolved Groundwater 26 people served
1 violation (5yr)
· All resolved
Usfs Strawberry Admin. Site
All resolved Groundwater 26 people served
1 violation (5yr)
· All resolved
Highland Lakes #2
Groundwater 26 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
East Sonora Medical Center
Groundwater 25 people served
0 violations
Stonybrook Mhp
Groundwater 25 people served
0 violations
Rail Fence Motel
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Usfs Carlon Campgd
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
George Reed Inc.
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Surface water 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Surface water 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Ice House
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Surface water 25 people served
0 violations
Sylvan Court Water System
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
La Casa Loma River Store
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Surface water 25 people served
0 violations
Sand Flat # 1
Groundwater 25 people served
0 violations
Confidence Inn & Liquor Store
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
W.S. Chester
Groundwater 25 people served
0 violations
Wishing Well
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Sonora Mining Corp01
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Groundwater 25 people served
0 violations
Stage Stop Store & Sandwich
Groundwater 25 people served
0 violations
Club 108
Groundwater 25 people served
0 violations
Usfs Stanislaus Nf
Surface water 25 people served
0 violations
Highland Lks #1
Groundwater 25 people served
0 violations
Lake Ridge Inn
Groundwater 25 people served
0 violations
Sand Flat # 2
Groundwater 25 people served
0 violations
Bloomfield Cg #1
Groundwater 25 people served
0 violations
Sand Flat # 6
Groundwater 25 people served
0 violations
Shaws Flat Elementary School
Groundwater 24 people served
0 violations
Tuo. Co. Superint. Of Schoo
Groundwater 13 people served
0 violations
Columbia Hills Apartments
Groundwater 4 people served
0 violations
Curtis Creek Elementary School
Groundwater 0
0 violations
Usfs Stanislaus Nf
Surface water 0
0 violations
Usfs Stanislaus Nf
Surface water 0
0 violations
Tud-Scenic View/Scenic Brook
Surface water 0
0 violations
Lead tested: 0 ppb (limit: 15 ppb) ✓
Tud - Sugar Pine Water System
Unknown 0
0 violations
Usfs Stanislaus Nf
Groundwater 0
0 violations
Tud - Gibbs Ranch Water System
Surface water 0
0 violations
Tud-Cuesta Serena
Unknown 0
0 violations
Oakhaven
Groundwater 0
0 violations
Christian Heights Asembly Of God
Groundwater 0
0 violations
Contaminants Found
Revised Total Coliform RuleHealth-Based
Missed testing deadlines — not a detection of bacteria.
18 violations
All resolved
LEAD AND COPPER RULE REVISIONSHealth-Based
6 violations
Has active
NitrateMonitoring
At high levels, nitrate can cause blue baby syndrome in infants.
3 violations
All resolved
Lead & Copper Levels
Lead (Pb)
Within limit0 ppb measured
Action level: 15 ppb
Sampled: Jul 2024
How Does This Compare?
Sonora (95370) has more violations than 80% of US ZIP codes. The national average is 18.87 violations per ZIP over 5 years. This ZIP has 27.
Fewer violations 80th percentile More violations
Recommended Water Filters
Based on health-based violations detected in your area, these filter types are commonly used to address similar contaminants. Consult your water utility's Consumer Confidence Report for the most current data.
Reverse Osmosis System
Highly effective at removing heavy metals, dissolved solids, and a wide range of contaminants. Recommended for homes with lead or arsenic concerns.
Targets:Lead, Copper, Arsenic, Mercury, Cadmium
Look for:NSF/ANSI 58 certified
UV Water Purifier
Uses ultraviolet light to neutralize bacteria, viruses, and parasites without chemicals. Ideal for homes with microbial contamination concerns.
Targets:E. coli, Coliform, Giardia, Cryptosporidium
Look for:NSF/ANSI 55 (Class A) certified
Always look for filters certified by NSF International for the specific contaminants you want to remove. This is general educational information, not an endorsement of any specific product.