Water Quality in Hollister, CA (95045)

EPA violation data for public water systems serving ZIP code 95045.

Based on EPA compliance data. Not a substitute for an official water quality report from your utility.

3,659

Population

29

Water Systems

19

Violations (5yr)

9

Health-Based

Location

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Water Systems Serving This Area (29)

Hollister, City Of

1 health-based
Purchased surface water 26,017 people served
3 violations (5yr) · 1 health-based · All resolved

Sunnyslope County Water Dist

Purchased surface water 24,954 people served
0 violations

Nps Lassen Volcanic Np

Surface water 15,000 people served
0 violations

33rd District Agricultural Association

Groundwater 9,000 people served
0 violations

Henry Coe Park Rabbit Spring

Groundwater 7,000 people served
0 violations

San Juan Bautista, City Of

1 health-based
Groundwater 2,335 people served
2 violations (5yr) · 1 health-based
Lead tested: 0 ppb (limit: 15 ppb)

Henry Coe Park Widow Hobb Spr

Groundwater 2,000 people served
0 violations

Hollister Hills-Sheep Springs

Groundwater 1,200 people served
0 violations

Taylor Farms Retail, Inc.

Groundwater 1,055 people served
0 violations
Lead tested: 0 ppb (limit: 15 ppb)

Fremont Peak S.P Cold Spring

Groundwater 1,000 people served
0 violations

Csp Henry W. Coe State Park

Groundwater 898 people served
0 violations

Henry Coe Park Bl Oak Spring

Groundwater 600 people served
0 violations

True Leaf Farms, Llc.

All resolved
Groundwater 372 people served
1 violation (5yr) · All resolved
Lead tested: 0 ppb (limit: 15 ppb)

Anzar High School

Groundwater 268 people served
0 violations

Henry Coe Park Lost Spring

Groundwater 200 people served
0 violations

Hollister Hills-Lodge Well

Groundwater 164 people served
0 violations

Mcalpine Lake & Park

1 health-based
Groundwater 111 people served
2 violations (5yr) · 1 health-based
Lead tested: 0 ppb (limit: 15 ppb)

Mission Farm R.V. Park

1 health-based
Groundwater 110 people served
2 violations (5yr) · 1 health-based
Lead tested: 0 ppb (limit: 15 ppb)

Willis Construction Ws

1 health-based
Groundwater 76 people served
1 violation (5yr) · 1 health-based · All resolved
Lead tested: 0 ppb (limit: 15 ppb)

St. Francis Retreat Center

3 health-based
Groundwater under influence of surface water 69 people served
3 violations (5yr) · 3 health-based · All resolved

Enza Zaden Research

All resolved
Groundwater 65 people served
3 violations (5yr) · All resolved
Lead tested: 0 ppb (limit: 15 ppb)

Henry W Coe State Park Hdqtrs

Groundwater 54 people served
0 violations

Henry W Coe State Park - Dowdy Ranch

Groundwater 50 people served
0 violations

Betabel Rv Resort

1 health-based
Groundwater 49 people served
2 violations (5yr) · 1 health-based
Lead tested: 0 ppb (limit: 15 ppb)

Orchard Acres Subdivision

Groundwater 45 people served
0 violations

Mission Vineyard Mobile Home

Groundwater 40 people served
0 violations

Los Madrones Mwc

Groundwater 36 people served
0 violations

Hollister Hills Svra-Hdq Well

Surface water 25 people served
0 violations

Los Madrones Mutual Water Co

Groundwater 25 people served
0 violations

Contaminants Found

LEAD AND COPPER RULE REVISIONSHealth-Based
8 violations
Has active
TTHMHealth-Based
3 violations
All resolved
Surface Water Treatment RuleHealth-Based
3 violations
All resolved
ArsenicHealth-Based

A naturally occurring element that can cause cancer and other health effects at high levels.

1 violation
All resolved
Revised Total Coliform RuleMonitoring

Missed testing deadlines — not a detection of bacteria.

2 violations
All resolved
Total Haloacetic Acids (HAA5)Monitoring
1 violation
All resolved
Lead and Copper RuleMonitoring

Lead and copper testing requirement. Lead exposure can cause developmental harm in children.

1 violation
All resolved

Lead & Copper Levels

Lead (Pb)

Within limit
0 ppb measured Action level: 15 ppb

Sampled: Jan 2025

How Does This Compare?

Hollister (95045) has more violations than 76% of US ZIP codes. The national average is 18.87 violations per ZIP over 5 years. This ZIP has 19.

Fewer violations 76th 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

Activated Carbon Filter

Excellent for removing chlorine, chloramine, and disinfection byproducts like THMs and HAAs. Available as pitcher filters, countertop, or under-sink units.

Targets:THMs, HAAs, Chlorine, Chloramine, Taste & Odor

Look for:NSF/ANSI 42 & 53 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.

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