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Your Local Water Profile: Garden Grove

This profile explains what the applicable water provider reported for Garden Grove, what those results may mean throughout a home, and where property-specific testing or inspection may still be needed.

(877) 798-7487
A water provider's official report describes the public water system and its monitoring period — not every individual home. Plumbing materials, water age, temperature, and equipment can change water after it enters a property. Official report year: 2025.

First, confirm your water provider.

Water service can vary by address. Confirm the provider shown on your water bill before applying provider-specific results.

What the official water report says

Your water at a glance

City of Garden Grove

The report lists hardness as 303 ppm as CaCO3; this is not classified because the reported unit could not be normalized on the USGS scale.

USGS hardness scale: 0–60 soft; 61–120 moderately hard; 121–180 hard; >180 very hard, in mg/L as CaCO3.

Source: official report, p. 6

Golden State Water Company

The report lists hardness as 237 mg/L; this is very hard on the USGS scale.

USGS hardness scale: 0–60 soft; 61–120 moderately hard; 121–180 hard; >180 very hard, in mg/L as CaCO3.

Source: official report, p. 8

City of Garden Grove — compliance, as reported

The report states: “Last year, as in years past, your tap water met all U.S. EPA and state drinking water health standards. The City vigilantly safeguards its water supplies, and once again, we are proud to report that our system has never violated a maximum contaminant level (MCL) or any other water quality standard. [p. 3, Sources of Supply]

West Orange County Water System — compliance, as reported

The report states: “YOUR WATER MEETS ALL CURRENT FEDERAL AND STATE REQUIREMENTS [p. 8, West Orange County Water System – Source Water Quality]

Violations or advisories, as reported: In 2025, GSWC sampled groundwater sources in the West Orange County System for PFAS. Some sources had detections above the current notification levels. Notification letters were sent out to all local governing bodies, State Water Resources Control Board’s Division of Drinking Water and California Public Utilities Commission. [p. 9, Laboratory Analyses]

Units used on this page: parts per million as calcium carbonate — a standardized basis used for hardness and alkalinity; parts per million (ppm) — a concentration commonly corresponding to milligrams per liter in water; parts per billion (ppb) — a very small concentration commonly corresponding to micrograms per liter in water; parts per trillion (ppt) — a very small concentration commonly corresponding to nanograms per liter in water; milligrams per liter (mg/L) — about one part per million in water; micrograms per liter (µg/L) — commonly corresponding to parts per billion in water.

The Three C's — 1 of 3

Chemistry

What does this water tend to do in a home?

City of Garden Grove

Hardness, total

The utility reported: 18 grains per gallon

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Hardness, total

The utility reported: 303 ppm as CaCO3

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Hardness, total

The utility reported: 236 ppm as CaCO3

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Hardness, total

The utility reported: 14 grains/gal

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Calcium

The utility reported: 92 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Calcium

The utility reported: 56 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Magnesium

The utility reported: 17 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Magnesium

The utility reported: 22 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

pH

The utility reported: 7.9 pH unit

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY CONTINUED · report p. 7 · official report

pH

The utility reported: 8.3 units

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Alkalinity, total

The utility reported: 184 ppm as CaCO3

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Alkalinity, total

The utility reported: 108 ppm as CaCO3

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Total Dissolved Solids

The utility reported: 508 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Total Dissolved Solids

The utility reported: 545 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Chloride

The utility reported: 71 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Chloride

The utility reported: 92 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Sulfate

The utility reported: 114 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Sulfate

The utility reported: 182 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Sodium

The utility reported: 53 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY CONTINUED · report p. 7 · official report

Sodium

The utility reported: 88 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Lead 90th percentile

The utility reported: ND<5 ppb

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Copper 90th percentile

The utility reported: 0.13 ppm

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Chlorine Residual

The utility reported: 0.9 ppm

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

West Orange County Water System

Hardness [as CaCO3]

The utility reported: 237 mg/L

Other Parameters · report p. 8 · official report

Hardness [as CaCO3]

The utility reported: 13.8 grains/gal

Other Parameters · report p. 8 · official report

Calcium

The utility reported: 70.8 mg/L

Other Parameters · report p. 8 · official report

Magnesium

The utility reported: 14 mg/L

Other Parameters · report p. 8 · official report

pH

The utility reported: 7.9 pH units

Other Parameters · report p. 8 · official report

Alkalinity

The utility reported: 172 mg/L

Other Parameters · report p. 8 · official report

Total Dissolved Solids

The utility reported: 412 mg/L

Secondary Standards - Aesthetic · report p. 8 · official report

Chloride

The utility reported: 44.9 mg/L

Secondary Standards - Aesthetic · report p. 8 · official report

Sulfate

The utility reported: 92.7 mg/L

Secondary Standards - Aesthetic · report p. 8 · official report

Sodium

The utility reported: 48 mg/L

Other Parameters · report p. 8 · official report

Lead

The utility reported: Not detected at the report's stated reporting limit µg/L

Lead sampling in schools and residential plumbing · report p. 9 · official report

Copper

The utility reported: 0.25 mg/L

Inorganic Constituents · report p. 9 · official report

Chlorine [as Cl2]

The utility reported: 1.4 mg/L

Disinfection Byproducts and Disinfectant Residuals · report p. 9 · official report

Chloramine

The utility reported: Present

Laboratory Analyses · report p. 9 · official report

Chemistry is not a safety grade, and utility-level values do not guarantee conditions at a property.

The Three C's — 2 of 3

Contaminants

What was reported, and what do the applicable standards mean?

Legal limit — maximum contaminant level (MCL)

The highest level legally allowed in public drinking water under the applicable rule. Do not use MCL as a generic label for goals, action levels, notification levels, or independent guidelines. It is different from a non-enforceable health goal.

California health goal — public health goal (PHG)

A non-enforceable health-protective target developed for standard-setting context. It is not the California legal limit.

Federal health goal — maximum contaminant level goal (MCLG)

A non-enforceable EPA public-health target used in setting standards. It is not the legal limit.

Legal disinfectant-residual limit — maximum residual disinfectant level (MRDL)

The highest level of a drinking-water disinfectant allowed under the applicable rule. It is not an MCL for a contaminant.

City of Garden Grove — regulated contaminants reported as detected (21)

Chlorine Residual

The utility reported: 0.9 ppm

Reported range: 0.2 - 2.8

MRDL: 4 · Health goal (MRDLG): 4 — not an enforceable limit

Violation per report: No

Typical source, per the report: Disinfectant Added for Treatment

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

Haloacetic Acids

The utility reported: 8 ppb

Reported range: ND - 9.9

Legal limit (MCL): 60

Violation per report: No

Typical source, per the report: Byproducts of Chlorine Disinfection

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

Total Trihalomethanes

The utility reported: 16 ppb

Reported range: ND-36

Legal limit (MCL): 80

Violation per report: No

Typical source, per the report: Byproducts of Chlorine Disinfection

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

Copper

The utility reported: 0.13 ppm

Reported range: ND-0.23

AL: 1.3 · Health goal (PHG): 0.3 — not an enforceable limit

Violation per report: No

Typical source, per the report: Corrosion of Household Plumbing

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Lead

The utility reported: ND<5 ppb

Reported range: ND-8.3

AL: 15 · Health goal (PHG): 0.2 — not an enforceable limit

Violation per report: No

Typical source, per the report: Corrosion of Household Plumbing

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Gross Alpha Particle Activity

The utility reported: Not detected at the report's stated reporting limit pCi/L

Reported range: ND-3.8

Legal limit (MCL): 15 · Health goal (MCLG): 0 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Uranium

The utility reported: 8.2 pCi/L

Reported range: 5.9-10

Legal limit (MCL): 20 · Health goal (PHG): 0.43 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Arsenic

The utility reported: Not detected at the report's stated reporting limit ppb

Reported range: ND-3.7

Legal limit (MCL): 10 · Health goal (PHG): 0.004 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Barium

The utility reported: Not detected at the report's stated reporting limit ppm

Reported range: ND-0.12

Legal limit (MCL): 1 · Health goal (PHG): 2 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Chromium, Hexavalent

The utility reported: 1.3 ppb

Reported range: 0.19-2

Legal limit (MCL): 10 · Health goal (PHG): 0.02 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits; Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Fluoride

The utility reported: 0.46 ppm

Reported range: 0.41-0.55

Legal limit (MCL): 2 · Health goal (PHG): 1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Nitrate

The utility reported: 2.9 ppm as N

Reported range: 0.43 - 4

Legal limit (MCL): 10 · Health goal (PHG): 10 — not an enforceable limit

Violation per report: No

Typical source, per the report: Fertilizers, Septic Tanks

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Nitrate+Nitrite

The utility reported: 2.9 ppm as N

Reported range: 0.43 - 4

Legal limit (MCL): 10 · Health goal (PHG): 10 — not an enforceable limit

Violation per report: No

Typical source, per the report: Fertilizers, Septic Tanks

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perchlorate

The utility reported: 1.7 ppb

Reported range: ND - 3.2

Legal limit (MCL): 6 · Health goal (PHG): 1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Gross Alpha Particle Activity

The utility reported: Not detected at the report's stated reporting limit pCi/L

Reported range: ND-5

Legal limit (MCL): 15 · Health goal (MCLG): 0 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Gross Beta Particle Activity

The utility reported: Not detected at the report's stated reporting limit pCi/L

Reported range: ND-6

Legal limit (MCL): 50 · Health goal (MCLG): 0 — not an enforceable limit

Violation per report: No

Typical source, per the report: Decay of Natural and Man-made Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Uranium

The utility reported: 1 pCi/L

Reported range: ND-3

Legal limit (MCL): 20 · Health goal (PHG): 0.43 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Aluminum

The utility reported: 0.058 ppm

Reported range: ND - 0.082

Legal limit (MCL): 1 · Health goal (PHG): 0.6 — not an enforceable limit

Violation per report: No

Typical source, per the report: Treatment Process Residue, Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Barium

The utility reported: 0.13 ppm

Reported range: 0.13

Legal limit (MCL): 1 · Health goal (PHG): 2 — not an enforceable limit

Violation per report: No

Typical source, per the report: Refinery Discharge, Erosion of Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Bromate

The utility reported: 2.4 ppb

Reported range: ND - 8.4

Legal limit (MCL): 10 · Health goal (PHG): 0.1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Byproduct of Drinking Water Ozonation

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Fluoride treatment-related

The utility reported: 0.7 ppm

Reported range: 0.6 - 0.8

Legal limit (MCL): 2 · Health goal (PHG): 1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Water Additive for Dental Health

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

City of Garden Grove — unregulated monitoring and secondary (aesthetic) records (35)

Unregulated means monitored without an applicable enforceable legal limit (MCL) — it does not mean unimportant or illegal. Secondary records address aesthetic, cosmetic, or technical effects such as taste, odor, staining, or scale, and are not automatically primary health standards.

Color

The utility reported: 1 color units

Reported range: 1

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

Odor

The utility reported: 1 threshold odor number

Reported range: 1

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

Turbidity

The utility reported: Not detected at the report's stated reporting limit ntu

Reported range: ND-1.5

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE DISTRIBUTION SYSTEM WATER QUALITY · report p. 5 · official report

Color

The utility reported: Not detected at the report's stated reporting limit color units

Reported range: ND-3

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Odor

The utility reported: Not detected at the report's stated reporting limit threshold odor number

Reported range: ND-1

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Specific Conductance

The utility reported: 797 µmho/cm

Reported range: 490-999

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Turbidity

The utility reported: Not detected at the report's stated reporting limit ntu

Reported range: ND-0.3

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Boron

The utility reported: 0.1 ppm

Reported range: ND - 0.24

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Lithium

The utility reported: Not detected at the report's stated reporting limit ppb

Reported range: ND-11

Typical source, per the report: Various Natural and Man-made Sources

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluorobutanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-12

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluorobutanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-15

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro butane sulfonic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-3.8

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro butane sulfonic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-2.7

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoroheptanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-3

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro hexane sulfonic acid

The utility reported: 3.7 ppt

Reported range: ND-11

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro hexane sulfonic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-9.6

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluorohexanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-8.7

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluorohexanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND - 5.4

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro octane sulfonic acid

The utility reported: 6.1 ppt

Reported range: ND-19

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro octane sulfonic acid

The utility reported: 4 ppt

Reported range: ND-19

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro octanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-9

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoro octanoic acid

The utility reported: Not detected at the report's stated reporting limit ppt

Reported range: ND-8.1

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoropentanoic acid

The utility reported: 4.7 ppt

Reported range: ND-17

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Perfluoropentanoic acid

The utility reported: 2.9 ppt

Reported range: ND - 8.6

Typical source, per the report: Industrial Discharge

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Potassium

The utility reported: 3.8 ppm

Reported range: 2.6 - 4.9

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY CONTINUED · report p. 7 · official report

Vanadium, Total

The utility reported: 2.2 ppb

Reported range: ND - 3.8

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY CONTINUED · report p. 7 · official report

Aluminum

The utility reported: 58 ppb

Reported range: ND-82

Typical source, per the report: Treatment Process Residue, Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Color

The utility reported: 1 color units

Reported range: 1

Typical source, per the report: Naturally-occurring Organic Materials

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Specific Conductance

The utility reported: 873 µmho/cm

Reported range: 759 - 987

Typical source, per the report: Substances that Form Ions in Water

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Boron

The utility reported: 0.13 ppm

Reported range: 0.13

Typical source, per the report: Runoff or Leaching from Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Potassium

The utility reported: 4.3 ppm

Reported range: 3.8 - 4.8

Typical source, per the report: Runoff or Leaching from Natural Deposits

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Total Organic Carbon

The utility reported: 2.4 ppm

Reported range: 1.6-2.6

Typical source, per the report: Various Natural and Man-made Sources

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Turbidity - combined filter effluent Highest single turbidity measurement

The utility reported: 0.05 NTU

Reported range: 0.05

Typical source, per the report: Soil Runoff

METROPOLITAN WATER DISTRICT DIEMER FILTRATION PLANT · report p. 9 · official report

Turbidity - combined filter effluent Percentage of samples less than or equal to 0.3 NTU

The utility reported: 100% %

Reported range: 100%

Typical source, per the report: Soil Runoff

METROPOLITAN WATER DISTRICT DIEMER FILTRATION PLANT · report p. 9 · official report

Lithium

The utility reported: 21 ppb

Reported range: ND-35

UNREGULATED CONSTITUENTS REQUIRING MONITORING · report p. 9 · official report

West Orange County Water System — regulated contaminants reported as detected (15)

Turbidity Highest single measurement of the treated surface water

The utility reported: 0.05 NTU

TT: 1.0

Violation per report: No

Typical source, per the report: Soil runoff

Primary Standards - Health Based · report p. 8 · official report

Turbidity Lowest percent of all monthly readings less than 0.3 NTU

The utility reported: 100% %

TT: 95

Violation per report: No

Typical source, per the report: Soil runoff

Primary Standards - Health Based · report p. 8 · official report

Arsenic

The utility reported: 2.4 µg/L

Reported range: ND - 4.1

Legal limit (MCL): 10 · Health goal (PHG (MCLG)): 0.004 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of natural deposits; runoff from orchards; glass and electronics production wastes

Primary Standards - Health Based · report p. 8 · official report

Chromium, Hexavalent

The utility reported: 0.8 µg/L

Reported range: ND - 2.9

Legal limit (MCL): 10 · Health goal (PHG (MCLG)): 0.02 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of natural deposits; transformation of naturally occurring trivalent chromium to hexavalent chromium by natural processes and human activities, such as discharges from electroplating factories, leather tanneries, wood preservation, chemical synthesis, refractory production, and textile manufacturing facilities.

Primary Standards - Health Based · report p. 8 · official report

Fluoride

The utility reported: 0.5 mg/L

Reported range: 0.4 - 0.8

Legal limit (MCL): 2.0 · Health goal (PHG (MCLG)): 1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of natural deposits; water additive that promotes strong teeth; discharge from fertilizer and aluminum factories

Primary Standards - Health Based · report p. 8 · official report

Nitrate [as N]

The utility reported: 1.5 mg/L

Reported range: ND - 4.5

Legal limit (MCL): 10 · Health goal (PHG (MCLG)): 10 — not an enforceable limit

Violation per report: No

Typical source, per the report: Runoff and leaching from fertilizer use; leaching from septic tanks and sewage; erosion of natural deposits

Primary Standards - Health Based · report p. 8 · official report

Perchlorate

The utility reported: 1.1 µg/L

Reported range: ND - 3.2

Legal limit (MCL): 6 · Health goal (PHG (MCLG)): 1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Perchlorate is an inorganic chemical used in solid rocket propellant, fireworks, explosives, flares, matches, and a variety of industries. It usually gets into drinking water as a result of environmental contamination from historic aerospace or other industrial operations that used or use, store, or dispose of perchlorate and its salts.

Primary Standards - Health Based · report p. 8 · official report

Gross Alpha Activity

The utility reported: 5.17 pCi/L

Reported range: ND - 17.1

Legal limit (MCL): 15(a) · Health goal (PHG (MCLG)): (0) — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of natural deposits

Radioactive Constituents · report p. 8 · official report

Gross Beta Activity

The utility reported: 5.70 pCi/L

Reported range: ND - 17.1

Legal limit (MCL): 50(b) · Health goal (PHG (MCLG)): (0) — not an enforceable limit

Violation per report: No

Typical source, per the report: Decay of natural and manmade deposits

Radioactive Constituents · report p. 8 · official report

Uranium

The utility reported: 6.71 pCi/L

Reported range: ND - 21.9 (c)

Legal limit (MCL): 20 · Health goal (PHG (MCLG)): 0.43 — not an enforceable limit

Violation per report: No

Typical source, per the report: Erosion of natural deposits

Radioactive Constituents · report p. 8 · official report

Bromate

The utility reported: 2.4 µg/L

Reported range: ND - 8.4

Legal limit (MCL): 10 · Health goal (PHG (MRDLG)): 0.1 — not an enforceable limit

Violation per report: No

Typical source, per the report: Byproduct of drinking water disinfection

Disinfection Byproducts and Disinfectant Residuals · report p. 9 · official report

Chlorine [as Cl2]

The utility reported: 1.4 mg/L

Reported range: 0.1 - 3.8

MRDL: (4.0) · Health goal (PHG (MRDLG)): (4) — not an enforceable limit

Violation per report: No

Typical source, per the report: Drinking water disinfectant added for treatment

Disinfection Byproducts and Disinfectant Residuals · report p. 9 · official report

HAA5 [Sum of 5 Haloacetic Acids]

The utility reported: 6.0 µg/L

Reported range: ND - 7.2

Legal limit (MCL): 60

Violation per report: No

Typical source, per the report: Byproduct of drinking water disinfection

Disinfection Byproducts and Disinfectant Residuals · report p. 9 · official report

TTHMs [Total Trihalomethanes]

The utility reported: 30 µg/L

Reported range: 1.6 - 35

Legal limit (MCL): 80

Violation per report: No

Typical source, per the report: Byproduct of drinking water disinfection

Disinfection Byproducts and Disinfectant Residuals · report p. 9 · official report

Copper

The utility reported: 0.25 mg/L

Reported range: None of the 51 samples collected exceeded the action level.

AL: 1.3 · Health goal (PHG (MCLG)): 0.3 — not an enforceable limit

Violation per report: No

Typical source, per the report: Internal corrosion of household plumbing systems; erosion of natural deposits; leaching from wood preservatives

Inorganic Constituents · report p. 9 · official report

West Orange County Water System — unregulated monitoring and secondary (aesthetic) records (8)

Unregulated means monitored without an applicable enforceable legal limit (MCL) — it does not mean unimportant or illegal. Secondary records address aesthetic, cosmetic, or technical effects such as taste, odor, staining, or scale, and are not automatically primary health standards.

Chloride

The utility reported: 44.9 mg/L

Reported range: 12.0 - 99.0

Typical source, per the report: Runoff/leaching from natural deposits; seawater influence

Secondary Standards - Aesthetic · report p. 8 · official report

Specific Conductance

The utility reported: 647 µS/cm

Reported range: 363 - 987

Typical source, per the report: Substances that form ions when in water; seawater influence

Secondary Standards - Aesthetic · report p. 8 · official report

Sulfate

The utility reported: 92.7 mg/L

Reported range: 34.4 - 218

Typical source, per the report: Runoff/leaching from natural deposits; industrial wastes

Secondary Standards - Aesthetic · report p. 8 · official report

Total Dissolved Solids

The utility reported: 412 mg/L

Reported range: 204 - 625

Typical source, per the report: Runoff/leaching from natural deposits

Secondary Standards - Aesthetic · report p. 8 · official report

Turbidity

The utility reported: 0.1 units

Reported range: ND - 1

Typical source, per the report: Soil runoff

Secondary Standards - Aesthetic · report p. 8 · official report

Perfluorohexanesulfonic Acid (PFHxS)

The utility reported: 4.0 ng/L

Reported range: ND - 10.3 (e)

Typical source, per the report: Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities.

Unregulated Drinking Water Constituents · report p. 8 · official report

Perfluorooctanoic acid (PFOA)

The utility reported: 3.0 ng/L

Reported range: ND - 8.3 (e)

Typical source, per the report: Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities.

Unregulated Drinking Water Constituents · report p. 8 · official report

Perfluorooctane Sulfonate (PFOS)

The utility reported: 5.8 ng/L

Reported range: ND - 16.4 (e)

Typical source, per the report: Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities.

Unregulated Drinking Water Constituents · report p. 8 · official report

Detection, enforceable limits, health goals, advisory levels, and violations are different concepts.

The Three C's — 3 of 3

Corrosion

What conditions could influence pipes, fixtures, and a water heater?

City of Garden Grove

pH

The utility reported: 7.9 pH unit

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY CONTINUED · report p. 7 · official report

pH

The utility reported: 8.3 units

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Alkalinity, total

The utility reported: 184 ppm as CaCO3

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Alkalinity, total

The utility reported: 108 ppm as CaCO3

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Chloride

The utility reported: 71 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Chloride

The utility reported: 92 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Sulfate

The utility reported: 114 ppm

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

Sulfate

The utility reported: 182 ppm

2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER · report p. 8 · official report

Lead 90th percentile

The utility reported: ND<5 ppb

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Copper 90th percentile

The utility reported: 0.13 ppm

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Copper

The utility reported: 0.13 ppm

Reported range: ND-0.23

Typical source, per the report: Corrosion of Household Plumbing

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Lead

The utility reported: ND<5 ppb

Reported range: ND-8.3

Typical source, per the report: Corrosion of Household Plumbing

LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS · report p. 5 · official report

Gross Alpha Particle Activity

The utility reported: Not detected at the report's stated reporting limit pCi/L

Reported range: ND-3.8

Typical source, per the report: Erosion of Natural Deposits

2025 CITY OF GARDEN GROVE GROUNDWATER QUALITY · report p. 6 · official report

West Orange County Water System

pH

The utility reported: 7.9 pH units

Other Parameters · report p. 8 · official report

Alkalinity

The utility reported: 172 mg/L

Other Parameters · report p. 8 · official report

Chloride

The utility reported: 44.9 mg/L

Secondary Standards - Aesthetic · report p. 8 · official report

Sulfate

The utility reported: 92.7 mg/L

Secondary Standards - Aesthetic · report p. 8 · official report

Lead

The utility reported: Not detected at the report's stated reporting limit µg/L

Lead sampling in schools and residential plumbing · report p. 9 · official report

Copper

The utility reported: 0.25 mg/L

Inorganic Constituents · report p. 9 · official report

Gross Alpha Activity

The utility reported: 5.17 pCi/L

Reported range: ND - 17.1

Typical source, per the report: Erosion of natural deposits

Radioactive Constituents · report p. 8 · official report

This is system-level water-quality context, not a diagnosis of your home. Plumbing materials, water age, temperature, maintenance, and equipment design can materially change what happens at a specific property.

Whole-Home Relevance

What this may mean throughout your home

Local conditions can be relevant to equipment and fixtures — actual effects depend on your property.

Water heater (tank and tankless)

What the local report can tell us
The report's hardness and mineral values above are the system-level inputs most relevant to scale and sediment where water is heated.
What a homeowner may notice
Hardness minerals can contribute to scale on heating surfaces, sediment in tanks, and more frequent flushing or descaling needs.
What the report cannot tell us
Property-specific outcomes — actual effects depend on temperature, use, equipment design, installation, maintenance, and property plumbing.
Responsible next step
Inspect the actual water heater and plumbing when symptoms involve hot-water odor, scale, sediment, corrosion, flow, noise, or repeated service demand.

Dishwasher and washing machine

What the local report can tell us
Reported hardness and secondary (aesthetic) records are the relevant system-level context for spotting and residue.
What a homeowner may notice
Hard water can change soap behavior and may contribute to spotting on dishes and residue in laundry.
What the report cannot tell us
Property-specific outcomes — actual effects depend on temperature, use, equipment design, installation, maintenance, and property plumbing.
Responsible next step
Inspect the actual water heater and plumbing when symptoms involve hot-water odor, scale, sediment, corrosion, flow, noise, or repeated service demand.

Pipes, fixtures, faucets, and supply lines

What the local report can tell us
The corrosion-related inputs above (such as pH) describe the water entering the property — not the condition of any specific plumbing.
What a homeowner may notice
Mineral deposits can appear on aerators and fixtures; corrosion outcomes depend on materials, age, and water conditions together.
What the report cannot tell us
Property-specific outcomes — actual effects depend on temperature, use, equipment design, installation, maintenance, and property plumbing.
Responsible next step
Inspect the actual water heater and plumbing when symptoms involve hot-water odor, scale, sediment, corrosion, flow, noise, or repeated service demand.

Drinking and cooking water

What the local report can tell us
The contaminant records above show what the utility reported for the system and period, with each benchmark type labeled.
What a homeowner may notice
Taste, odor, or aesthetic preferences can be noticeable even when health-based standards are met.
What the report cannot tell us
Property-specific outcomes — actual effects depend on temperature, use, equipment design, installation, maintenance, and property plumbing.
Responsible next step
Inspect the actual water heater and plumbing when symptoms involve hot-water odor, scale, sediment, corrosion, flow, noise, or repeated service demand.

Decision Pathways

Treatment pathways to evaluate

Treatment is a decision pathway, not a product conclusion — no equipment can be responsibly chosen from city-level data alone.

The evaluation sequence we follow, in order:

  1. 1Define the concern
  2. 2Verify utility-level and home-specific evidence
  3. 3Choose point of treatment
  4. 4Verify the exact certified reduction claim for the exact model
  5. 5Review tradeoffs and maintenance

Water filtration

Objective it can address
Specific substances or aesthetic conditions (taste, odor, chlorine character).
Point of treatment
Point of entry or point of use, depending on the objective.
Limitations to verify
A filter works only for the conditions and reduction claims its exact design and certification support — filtration does not soften water.

Certification note: a standard number alone doesn't prove a product reduces every contaminant — the exact model's certified claim must match your objective.

Water softening

Objective it can address
Hardness minerals (calcium and magnesium) and the scale they can contribute to.
Point of treatment
Typically point of entry, confirmed by evaluation.
Limitations to verify
Softening primarily exchanges hardness minerals — it is not a universal contaminant-removal device.

Certification note: a standard number alone doesn't prove a product reduces every contaminant — the exact model's certified claim must match your objective.

Reverse osmosis

Objective it can address
Specified dissolved substances at a dedicated outlet, commonly drinking and cooking water.
Point of treatment
Typically point of use.
Limitations to verify
Produces a reject-water stream and needs pressure and maintenance; verify the exact NSF/ANSI 58 reduction claims for the exact model. It is not automatically the best system for every home.

Certification note: a standard number alone doesn't prove a product reduces every contaminant — the exact model's certified claim must match your objective.

When testing is the right next step

Use a certified laboratory when the concern is tap-specific, property-specific, or not resolved by the utility report.

When inspection is the right next step

Inspect the actual water heater and plumbing when symptoms involve hot-water odor, scale, sediment, corrosion, flow, noise, or repeated service demand.

Evidence You Can Check

Official reports, sources, and methodology

Official report — City of Garden Grove

ANNUAL WATER QUALITY REPORT Reporting Year 2025 · data year 2025 · Current 2025 monitoring cycle

View the 2025 City of Garden Grove Consumer Confidence Report

Source water, per the report: Your drinking water is a blend of mostly groundwater from 9 wells in the Orange County groundwater basin and surface water imported by MWDSC. Imported water sources are the State Water Project from Northern California and the Colorado River Aqueduct.

Official report — West Orange County Water System

Consumer Confidence Report on Water Quality for 2025 · data year 2025 · Current 2025 monitoring cycle

View the 2025 West Orange County Water System Consumer Confidence Report

Source water, per the report: Water delivered to customers in the West Orange County System is a blend of treated groundwater pumped from the Orange County Groundwater Basin and imported water from the Colorado River Aqueduct and the State Water Project (imported and distributed by the Metropolitan Water District of Southern California).

This is system-level water-quality context, not a diagnosis of your home. Plumbing materials, water age, temperature, maintenance, and equipment design can materially change what happens at a specific property.
The official utility report and controlling regulator determine compliance status. This page does not replace utility notices or regulator guidance.
Water service varies by address. Confirm the serving utility before applying provider-specific results.
Profile verified as of 2026-07-12 (framework v1.0). Values, units, ranges, periods, and compliance wording are preserved from each official report. Spot an error? Call (877) 798-7487 or use the contact form and we'll review it against the source report and correct it.

Property-Specific Next Step

Request a Water Quality Evaluation

Request a water-heater and water-quality evaluation tailored to the property, equipment, and homeowner objective.

A property-specific evaluation confirms your goals, provider, tap conditions, plumbing, equipment, installation, and maintenance before any treatment recommendation — this profile alone is never used to prescribe equipment.

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