Water Quality Report · Updated May 12, 2026

RIVERSIDE, CITY OF

Serving 298,398 residents in RIVERSIDE, California .

National rank 0th percentile
California rank 1th percentile
Data confidence Medium
Quick answer

RIVERSIDE, CITY OF delivers tap water graded F (46/100) by TapWaterSafety.org. The utility serves approximately 298,398 residents in RIVERSIDE, California using groundwater under direct influence. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Arsenic significantly above health guideline; Chromium (hexavalent) significantly above health guideline. For questions, the utility can be reached at 951-826-8950.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
298,398
People served
1
City served
25
Contaminants detected
12
Above health guidelines
0
EPA violations (5 yr)

Is RIVERSIDE tap water safe to drink?

RIVERSIDE, CITY OF delivers tap water that earns a grade of F (46/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.

The utility serves 298,398 residents in RIVERSIDE, drawing from groundwater under direct influence.

Public testing data identifies 12 contaminants in this water above EWG's health-based guidelines, including: Perfluorohexane sulfonate (PFHXS), Arsenic, Chromium (hexavalent), Nitrate, Perfluorooctanoic acid (PFOA), Total trihalomethanes (TTHMs), Haloacetic acids (HAA9), Uranium, Perfluorooctane sulfonate (PFOS), Radium, combined (-226 and -228), 1,4-Dioxane, Perchlorate. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for RIVERSIDE, CITY OF.

PFAS contamination

Severe concern

Perfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.

Perfluorohexane sulfonate (PFHXS) significantly above health guideline

Moderate concern

Perfluorohexane sulfonate (PFHXS) detected at 2.24 ppt, 2238x above the EWG health guideline of 0.001 ppt.

Arsenic significantly above health guideline

Moderate concern

Arsenic detected at 2.1 ppb, 526x above the EWG health guideline of 0.004 ppb.

Chromium (hexavalent) significantly above health guideline

Moderate concern

Chromium (hexavalent) detected at 2.07 ppb, 104x above the EWG health guideline of 0.02 ppb.

Contact RIVERSIDE, CITY OF

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for RIVERSIDE

Filters matched to the specific contaminants in this water supply.

Reverse Osmosis or NSF P473 certified carbon

$80-$750

Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →
Clearly Filtered Pitcher Filter
$80-$95 NSF 42, 53, 401, P473
Editorial pick · affiliate link coming soon

Reverse Osmosis

$249-$750

Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

Score breakdown

This utility's overall score of 46/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
0 / 20
Compliance History
10 / 10
Source Water Vulnerability
6 / 10

Contaminants detected — international standards comparison

Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →

Contaminant Detected EWG
US health-based
EPA
US legal
EU DWD
Europe
WHO
global
CA PHG
strictest US
Tested
sample year
Status
Perfluorohexane sulfonate (PFHXS)
PFAS
2.24 ppt 0.001 10.0 2238× over
Arsenic
Heavy metal
2.1 ppb 0.004 10.0 10 10 0.004 526× over
Chromium (hexavalent)
Heavy metal
2.07 ppb 0.02 104× over
Nitrate
Inorganic
5.54 ppm 0.14 10.0 11.3 11.3 10 40× over
Perfluorooctanoic acid (PFOA)
PFAS
3.11 ppt 0.09 4.0 100 100 0.007 35× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
5.0 ppb 0.15 80.0 100 33× over
Haloacetic acids (HAA9)
Disinfection byproduct
1.14 ppb 0.06 19× over
Uranium
Radiological
6.72 pCi/L 0.43 20.0 30 30 0.43 16× over
Perfluorooctane sulfonate (PFOS)
PFAS
3.8 ppt 0.3 4.0 100 100 1 13× over
Radium, combined (-226 and -228)
Radiological
0.11 pCi/L 0.05 5.0 2.3× over
1,4-Dioxane
Semi-volatile organic compound
0.65 ppb 0.35 50 1 1.9× over
Perchlorate
Disinfection byproduct
1.27 ppb 1.0 1.3× over
Vanadium
Other
6.38 ppb 21.0 Below guideline
Chlorate
Disinfection byproduct
62.3 ppb 210.0 Below guideline
Molybdenum
Other
4.23 ppb 40.0 Below guideline
Chloromethane
Other
0.0273 ppb 2.69 Below guideline
Perfluoropentanoic Acid (PFPeA)
PFAS
4.84 ppt 1000.0 Below guideline
Perfluorohexanoic Acid (PFHxA)
PFAS
3.95 ppt 1000.0 Below guideline
Perfluorobutanoic Acid (PFBA)
PFAS
3.08 ppt 1000.0 Below guideline
Perfluorobutane sulfonate (PFBS)
PFAS
1.93 ppt 2000.0 Below guideline
Strontium
Radiological
0.493 ppb 1500.0 Below guideline
Perfluoroheptanoic acid (PFHPA)
PFAS
0.249 ppt 1000.0 Below guideline
Fluoride
Inorganic
0.481 ppm 4.0 1.5 1.5 Below guideline
Germanium
Other
0.278 ppb Below guideline
Lithium
Other
4.53 ppb Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

RIVERSIDE, CITY OF service area

This water system serves 1 community in Riverside County, California. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
CA3310031
Owner type
Local government
Source water
Groundwater under direct influence
Service connections
66,567
Service area
RIVERSIDE, Riverside County, California