What's in Western MWD — Riverside, Ca, CA tap water

52 contaminants were measured in the Western MWD — Riverside, Ca, CA water system's 2023 annual report. Each is shown below against its federal limit — 2 sit at or above that limit.

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Reporting year: 2023
Contaminants measured: 52
Over federal limit: 2
Approaching the limit: 0
Worst contaminant: Copper
Service area: CA
Source: Utility CCR

At or above the federal limit

Metals

Contaminant	Measured	Federal limit	Status
CopperA metal that enters water from corroding household plumbing.	1.3 mg/LReported levelAction Level @ 90th Percentile	None set	At or above the limit
+By source (2)— California Public Health Goal (PHG), Detection Limits for Purposes of Reporting (DLR) California Public Health Goal (PHG)Zone 23% of limit Detection Limits for Purposes of Reporting (DLR)Zone 4% of limit
LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures.	15 ug/LReported levelAction Level @ 90th Percentile	None set	At or above the limit
+By source (2)— Detection Limits for Purposes of Reporting (DLR), California Public Health Goal (PHG) Detection Limits for Purposes of Reporting (DLR)Zone 33% of limit California Public Health Goal (PHG)Zone 1% of limit
ArsenicA naturally occurring element that also enters water from industry and agriculture.	2 ug/LAverageMurrieta Service Area Local Groundwater	None set	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg2 ug/Lrange0–19 ug/L190% of limit Riverside Service Area Local GroundwaterZone avgNot detected ug/Lrange0–6.5 ug/L65% of limit Murrieta Service Area Surface WaterZone avgNot detected ug/Lrange0–2.3 ug/L23% of limit Rainbow Service Area Surface WaterZone avgNot detected ug/L0% of limit Riverside Service Area Surface WaterZone avgNot detected ug/L0% of limit
BariumA metal from erosion of natural deposits and industrial discharge.	0.1 mg/LAverageMurrieta Service Area Local Groundwater	2 mg/LMCL	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Surface Water, Murrieta Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg0.1 mg/Lrange0–0.3 mg/L15% of limit Riverside Service Area Surface WaterZone avgNot detected mg/L0% of limit Murrieta Service Area Surface WaterZone avgNot detected mg/L0% of limit Riverside Service Area Local GroundwaterZone avgNot detected mg/L0% of limit Rainbow Service Area Surface WaterZone avgNot detected mg/L0% of limit
SeleniumA trace element from natural deposits and industrial discharge.	Not detected ug/LAverageRainbow Service Area Surface Water	None set	Within the limit
+By source (5)— Riverside Service Area Local Groundwater, Murrieta Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avgNot detected ug/Lrange0–16 ug/L32% of limit Murrieta Service Area Local GroundwaterZone avgNot detected ug/Lrange0–12 ug/L24% of limit Rainbow Service Area Surface WaterZone avgNot detected ug/L0% of limit Riverside Service Area Surface WaterZone avgNot detected ug/L0% of limit Murrieta Service Area Surface WaterZone avgNot detected ug/L0% of limit
AluminumA common element sometimes used as a treatment coagulant.	74 ug/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Surface Water, Rainbow Service Area Surface Water, Riverside Service Area Surface Water +2 more Murrieta Service Area Surface WaterZone avgNot detected ug/Lrange0–160 ug/L Rainbow Service Area Surface WaterZone avg74 ug/Lrange0–160 ug/L Riverside Service Area Surface WaterZone avgNot detected ug/Lrange0–110 ug/L Murrieta Service Area Local GroundwaterZone avgNot detected ug/Lrange0–54 ug/L Riverside Service Area Local GroundwaterZone avgNot detected ug/Lrange0–52 ug/L
BoronA naturally occurring element from rock and soil.	130 ug/LAverageRainbow Service Area Surface Water	1000 ug/LNL	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg124 ug/Lrange0–508 ug/L Riverside Service Area Local GroundwaterZone avgNot detected ug/Lrange0–210 ug/L Murrieta Service Area Surface WaterZone avg127 ug/Lrange0–175 ug/L Rainbow Service Area Surface WaterZone avg130 ug/L Riverside Service Area Surface WaterZone avg130 ug/L
CalciumA naturally occurring mineral that contributes to water hardness.	62 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Riverside Service Area Local Groundwater +2 more Murrieta Service Area Local GroundwaterZone avg43 mg/Lrange5–110 mg/L Murrieta Service Area Surface WaterZone avg36 mg/Lrange14–83 mg/L Riverside Service Area Local GroundwaterZone avg46 mg/Lrange17–67 mg/L Rainbow Service Area Surface WaterZone avg62 mg/Lrange61–62 mg/L Riverside Service Area Surface WaterZone avg18 mg/Lrange15–22 mg/L
Chromium, HexavalentHexavalent chromium ('chromium-6') — the more toxic form of chromium.	1.2 ug/LAverageRiverside Service Area Local Groundwater	None set	Detected — no federal limit
+By source (5)— Riverside Service Area Local Groundwater, Rainbow Service Area Surface Water, Murrieta Service Area Local Groundwater +2 more Riverside Service Area Local GroundwaterZone avg1.2 ug/Lrange0–2.1 ug/L Rainbow Service Area Surface WaterZone avgNot detected ug/L Murrieta Service Area Local GroundwaterZone avgNot detected ug/L Murrieta Service Area Surface WaterZone avgNot detected ug/L Riverside Service Area Surface WaterZone avgNot detected ug/L
GermaniumA trace metalloid found in some source water.	Not detected ug/LAverageRiverside Service Area Local Groundwater	None set	Detected — no federal limit
IronA naturally occurring metal common in groundwater.	Not detected ug/LAverageRiverside Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avgNot detected ug/Lrange0–668 ug/L Riverside Service Area Surface WaterZone avgNot detected ug/L Rainbow Service Area Surface WaterZone avgNot detected ug/L Murrieta Service Area Surface WaterZone avgNot detected ug/L Riverside Service Area Local GroundwaterZone avgNot detected ug/L
LithiumA naturally occurring element found in some groundwater.	28 ug/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Surface Water, Rainbow Service Area Surface Water, Riverside Service Area Local Groundwater +2 more Murrieta Service Area Surface WaterZone avg9 ug/Lrange0–32 ug/L Rainbow Service Area Surface WaterZone avg28 ug/Lrange24–32 ug/L Riverside Service Area Local GroundwaterZone avgNot detected ug/Lrange0–9.1 ug/L Murrieta Service Area Local GroundwaterZone avgNot detected ug/L Riverside Service Area Surface WaterZone avgNot detected ug/L
MagnesiumA naturally occurring mineral that contributes to water hardness.	22 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg6.4 mg/Lrange0–44 mg/L Murrieta Service Area Surface WaterZone avg15 mg/Lrange7.4–29 mg/L Rainbow Service Area Surface WaterZone avg22 mg/Lrange22–23 mg/L Riverside Service Area Local GroundwaterZone avg9.3 mg/Lrange2.5–13 mg/L Riverside Service Area Surface WaterZone avg9.7 mg/Lrange8.4–11 mg/L
ManganeseA naturally occurring metal from soil and rock.	Not detected ug/LAverageRiverside Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avgNot detected ug/Lrange0–37 ug/L Riverside Service Area Surface WaterZone avgNot detected ug/L Rainbow Service Area Surface WaterZone avgNot detected ug/L Riverside Service Area Local GroundwaterZone avgNot detected ug/L Murrieta Service Area Surface WaterZone avgNot detected ug/L
PotassiumA naturally occurring mineral from rock and soil.	4.8 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg2.3 mg/Lrange0–7.2 mg/L Murrieta Service Area Surface WaterZone avg3.5 mg/Lrange1.9–5.9 mg/L Rainbow Service Area Surface WaterZone avg4.8 mg/Lrange4.6–4.9 mg/L Riverside Service Area Local GroundwaterZone avg1.9 mg/Lrange1.1–3.4 mg/L Riverside Service Area Surface WaterZone avg2.5 mg/Lrange1.9–3.1 mg/L
SilicaA naturally occurring compound from sand and rock.	14 mg/LAverageRiverside Service Area Local Groundwater	None set	Detected — no federal limit
+By source (3)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water Murrieta Service Area Local GroundwaterZone avg14 mg/Lrange5–50 mg/L Riverside Service Area Local GroundwaterZone avg14 mg/Lrange5.3–19 mg/L Murrieta Service Area Surface WaterZone avg7.2 mg/Lrange3.6–15 mg/L
SodiumA naturally occurring salt component.	93 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg65 mg/Lrange23–214 mg/L Murrieta Service Area Surface WaterZone avg65 mg/Lrange30–121 mg/L Rainbow Service Area Surface WaterZone avg93 mg/Lrange91–95 mg/L Riverside Service Area Surface WaterZone avg44 mg/Lrange35–54 mg/L Riverside Service Area Local GroundwaterZone avg35 mg/Lrange16–44 mg/L
Vanadium	Not detected ug/LAverageRiverside Service Area Local Groundwater	50 ug/LNL	Detected — no federal limit
+By source (4)— Riverside Service Area Local Groundwater, Riverside Service Area Surface Water, Murrieta Service Area Surface Water +1 more Riverside Service Area Local GroundwaterZone avgNot detected ug/Lrange0–6.3 ug/L Riverside Service Area Surface WaterZone avgNot detected ug/L Murrieta Service Area Surface WaterZone avgNot detected ug/L Rainbow Service Area Surface WaterZone avgNot detected ug/L

Disinfection byproducts

Contaminant	Measured	Federal limit	Status
BromateA disinfection byproduct formed when bromide-containing water is treated with ozone.	7.9 ug/LAverageRiverside	0.1 ug/LPublic health goal	Within the limit
TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter.	42 ug/LAverageRiverside	None set	Within the limit
HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter.	13 ug/LAverageMurrieta	None set	Within the limit
ChlorateA byproduct that can form during disinfection, especially when hypochlorite solutions degrade.	80 ug/LAverageRainbow Service Area Surface Water	800 ug/LNL	Detected — no federal limit
+By source (3)— Rainbow Service Area Surface Water, Murrieta Service Area Surface Water, Riverside Service Area Surface Water Rainbow Service Area Surface WaterZone avg80 ug/L Murrieta Service Area Surface WaterZone avg80 ug/L Riverside Service Area Surface WaterZone avg78 ug/L
NDMA	2.5 ng/LAverageMurrieta Service Area Surface Water	10 ng/LNL	Detected — no federal limit
+By source (4)— Murrieta Service Area Surface Water, Rainbow Service Area Surface Water, Riverside Service Area Surface Water +1 more Murrieta Service Area Surface WaterZone avg2.5 ng/L Rainbow Service Area Surface WaterZone avg2.5 ng/L Riverside Service Area Surface WaterZone avgNot detected ng/L Riverside Service Area Local GroundwaterZone avgNot detected ng/L
PerchlorateA chemical used in rocket fuel and fireworks that can also form during disinfection.	1.3 ug/LAverageRiverside Service Area Local Groundwater	None set	Detected — no federal limit
+By source (5)— Riverside Service Area Local Groundwater, Murrieta Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avg1.3 ug/Lrange0–2.9 ug/L Murrieta Service Area Local GroundwaterZone avgNot detected ug/L Rainbow Service Area Surface WaterZone avgNot detected ug/L Murrieta Service Area Surface WaterZone avgNot detected ug/L Riverside Service Area Surface WaterZone avgNot detected ug/L

Physical & aggregate

Contaminant	Measured	Federal limit	Status
TurbidityA measure of cloudiness from suspended particles in the water.	0.74 NTUAverageMurrieta Service Area Surface Water	None set	Within the limit
+By source (4)— Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water, Riverside Service Area Surface Water +1 more Riverside Service Area Local GroundwaterZone avg0.17 NTUrange99.3 NTU9930% of limit Murrieta Service Area Surface WaterZone avg0.74 NTU74% of limit Riverside Service Area Surface WaterZone avg0.08 NTU8% of limit Rainbow Service Area Surface WaterZone avg0.07 NTU7% of limit
AlkalinityA measure of the water's capacity to neutralize acids.	117 mg/LAverageRiverside Service Area Local Groundwater	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg101 mg/Lrange23–210 mg/L Riverside Service Area Local GroundwaterZone avg117 mg/Lrange40–180 mg/L Murrieta Service Area Surface WaterZone avg87 mg/Lrange57–135 mg/L Rainbow Service Area Surface WaterZone avg105 mg/Lrange103–107 mg/L Riverside Service Area Surface WaterZone avg70 mg/Lrange68–71 mg/L
ColorA measure of visible tint in the water.	Not detectedAverageMurrieta	None set	Detected — no federal limit
HardnessA measure of dissolved calcium and magnesium minerals.	242 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg134 mg/Lrange14–457 mg/L Murrieta Service Area Surface WaterZone avg149 mg/Lrange65–326 mg/L Rainbow Service Area Surface WaterZone avg242 mg/Lrange242–243 mg/L Riverside Service Area Local GroundwaterZone avg154 mg/Lrange54–210 mg/L Riverside Service Area Surface WaterZone avg84 mg/Lrange68–99 mg/L
OdorA measure of detectable smell in the water.	Not detectedAverageRainbow	None set	Detected — no federal limit
pHA measure of how acidic or basic the water is.	8.6AverageRiverside	None set	Detected — no federal limit
Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content.	910AverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Surface Water, Murrieta Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Murrieta Service Area Surface WaterZone avg603range280–1210 Murrieta Service Area Local GroundwaterZone avg579range307–1045 Rainbow Service Area Surface WaterZone avg910range903–917 Riverside Service Area Local GroundwaterZone avg470range200–580 Riverside Service Area Surface WaterZone avg392range317–466
TOCTotal organic carbon — a measure of organic material dissolved in the water.	2.6 mg/LAverageMurrieta Service Area Surface Water	None set	Detected — no federal limit
+By source (4)— Murrieta Service Area Surface Water, Rainbow Service Area Surface Water, Riverside Service Area Surface Water +1 more Murrieta Service Area Surface WaterZone avg2.6 mg/Lrange2–3.2 mg/L Rainbow Service Area Surface WaterZone avg2.6 mg/Lrange2.3–3 mg/L Riverside Service Area Surface WaterZone avg2.2 mg/Lrange1.5–2.5 mg/L Murrieta Service Area Local GroundwaterZone avgNot detected mg/Lrange0–2.3 mg/L
Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts.	566 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Surface Water, Murrieta Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Murrieta Service Area Surface WaterZone avg361 mg/Lrange157–715 mg/L Murrieta Service Area Local GroundwaterZone avg350 mg/Lrange196–582 mg/L Rainbow Service Area Surface WaterZone avg566 mg/Lrange560–572 mg/L Riverside Service Area Local GroundwaterZone avg292 mg/Lrange120–380 mg/L Riverside Service Area Surface WaterZone avg220 mg/Lrange178–263 mg/L

Inorganic chemicals

Contaminant	Measured	Federal limit	Status
NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits.	5 mg/LAverageRiverside Service Area Local Groundwater	10 mg/LMCL	Within the limit
+By source (5)— Riverside Service Area Local Groundwater, Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avg5 mg/Lrange2.8–6.8 mg/L68% of limit Murrieta Service Area Local GroundwaterZone avg0.8 mg/Lrange0–3.4 mg/L34% of limit Murrieta Service Area Surface WaterZone avgNot detected mg/Lrange0–1.6 mg/L16% of limit Riverside Service Area Surface WaterZone avg0.6 mg/L6% of limit Rainbow Service Area Surface WaterZone avgNot detected mg/L0% of limit
FluorideA mineral often added to drinking water to help prevent tooth decay.	0.7 mg/LAverageRiverside Service Area Surface Water	4 mg/LMCL	Within the limit
+By source (5)— Riverside Service Area Surface Water, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +2 more Riverside Service Area Surface WaterZone avg0.7 mg/Lrange0.6–0.9 mg/L23% of limit Murrieta Service Area Surface WaterZone avg0.2 mg/Lrange0–0.8 mg/L20% of limit Rainbow Service Area Surface WaterZone avg0.7 mg/Lrange0.6–0.8 mg/L20% of limit Riverside Service Area Local GroundwaterZone avg0.2 mg/Lrange0–0.5 mg/L13% of limit Murrieta Service Area Local GroundwaterZone avg0.2 mg/Lrange0–0.4 mg/L10% of limit
Chlorodibromoacetic acidA brominated haloacetic acid disinfection byproduct.	0.08 ug/LAverageRiverside Service Area Local Groundwater	None set	Within the limit
NitriteA compound from fertilizer runoff, sewage, and erosion of natural deposits.	Not detected mg/LAverageRiverside Service Area Local Groundwater	1 mg/LMCL	Within the limit
+By source (5)— Murrieta Service Area Surface Water, Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater +2 more Murrieta Service Area Surface WaterZone avgNot detected mg/Lrange0–0.8 mg/L80% of limit Murrieta Service Area Local GroundwaterZone avgNot detected mg/Lrange0–0.53 mg/L53% of limit Riverside Service Area Local GroundwaterZone avgNot detected mg/L0% of limit Riverside Service Area Surface WaterZone avgNot detected mg/L0% of limit Rainbow Service Area Surface WaterZone avgNot detected mg/L0% of limit
ChlorideA naturally occurring salt compound.	96 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg87 mg/Lrange10–150 mg/L Murrieta Service Area Surface WaterZone avg75 mg/Lrange38–120 mg/L Rainbow Service Area Surface WaterZone avg96 mg/Lrange92–100 mg/L Riverside Service Area Local GroundwaterZone avg48 mg/Lrange20–81 mg/L Riverside Service Area Surface WaterZone avg54 mg/Lrange41–67 mg/L
SulfateA naturally occurring mineral from rock and soil.	199 mg/LAverageRainbow Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Murrieta Service Area Surface Water, Rainbow Service Area Surface Water, Murrieta Service Area Local Groundwater +2 more Murrieta Service Area Surface WaterZone avg92 mg/Lrange15–224 mg/L Rainbow Service Area Surface WaterZone avg199 mg/Lrange195–203 mg/L Murrieta Service Area Local GroundwaterZone avg47 mg/Lrange10–177 mg/L Riverside Service Area Local GroundwaterZone avg40 mg/Lrange4–72 mg/L Riverside Service Area Surface WaterZone avg34 mg/Lrange21–47 mg/L

Disinfectants

Contaminant	Measured	Federal limit	Status
ChloramineA longer-lasting disinfectant made by combining chlorine with ammonia.	1.97 mg/LAverageRainbow	None set	Within the limit

Radionuclides

Contaminant	Measured	Federal limit	Status
Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances.	3.5 pCi/LAverageMurrieta Service Area Local Groundwater	15 pCi/LMCL	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avg3.5 pCi/Lrange0–10.6 pCi/L71% of limit Riverside Service Area Local GroundwaterZone avgNot detected pCi/Lrange0–4.7 pCi/L31% of limit Rainbow Service Area Surface WaterZone avgNot detected pCi/Lrange0–4 pCi/L27% of limit Murrieta Service Area Surface WaterZone avgNot detected pCi/Lrange0–4 pCi/L27% of limit Riverside Service Area Surface WaterZone avgNot detected pCi/L0% of limit
Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements.	Not detected pCi/LAverageRiverside Service Area Surface Water	0.05 pCi/LPublic health goal	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Surface Water, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avgNot detected pCi/Lrange0–1.2 pCi/L24% of limit Riverside Service Area Surface WaterZone avgNot detected pCi/Lrange0–1 pCi/L20% of limit Rainbow Service Area Surface WaterZone avgNot detected pCi/L0% of limit Murrieta Service Area Surface WaterZone avgNot detected pCi/L0% of limit Riverside Service Area Local GroundwaterZone avgNot detected pCi/L0% of limit
Gross Beta Particle ActivityGross beta particle activity — a combined measure of beta-emitting radioactive substances.	12 pCi/LAverageMurrieta Service Area Surface Water	None set	Detected — no federal limit
+By source (4)— Murrieta Service Area Local Groundwater, Murrieta Service Area Surface Water, Rainbow Service Area Surface Water +1 more Murrieta Service Area Local GroundwaterZone avg7.5 pCi/Lrange0–20 pCi/L Murrieta Service Area Surface WaterZone avg12 pCi/Lrange0–19 pCi/L Rainbow Service Area Surface WaterZone avg4 pCi/Lrange0–5 pCi/L Riverside Service Area Surface WaterZone avgNot detected pCi/L
UraniumA naturally occurring radioactive metal from erosion of natural deposits.	3.4 pCi/LAverageRiverside Service Area Local Groundwater	20 pCi/LMCL	Detected — no federal limit
+By source (5)— Riverside Service Area Local Groundwater, Murrieta Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avg3.4 pCi/Lrange0–11.7 pCi/L Murrieta Service Area Local GroundwaterZone avgNot detected pCi/Lrange0–6.6 pCi/L Rainbow Service Area Surface WaterZone avg2 pCi/Lrange0–3 pCi/L Murrieta Service Area Surface WaterZone avgNot detected pCi/Lrange0–3 pCi/L Riverside Service Area Surface WaterZone avgNot detected pCi/L

PFAS ("forever chemicals")

Contaminant	Measured	Federal limit	Status
Perfluorohexanesulfonic acidPerfluorohexanesulfonic acid, a PFAS 'forever chemical.'	Not detected ng/LAverageRiverside Service Area Surface Water	3 ng/LNL	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Riverside Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avgNot detected ng/Lrange0–3 ng/L30% of limit Riverside Service Area Local GroundwaterZone avgNot detected ng/Lrange0–3 ng/L30% of limit Riverside Service Area Surface WaterZone avgNot detected ng/L0% of limit Murrieta Service Area Surface WaterZone avgNot detected ng/L0% of limit Rainbow Service Area Surface WaterZone avgNot detected ng/L0% of limit
PFOAPerfluorooctanoic acid, a PFAS 'forever chemical' once used in nonstick and stain-resistant products.	Not detected ng/LAverageMurrieta Service Area Local Groundwater	5.1 ng/LNL	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Rainbow Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avgNot detected ng/Lrange0–4.7 ng/L118% of limit Riverside Service Area Local GroundwaterZone avgNot detected ng/L0% of limit Rainbow Service Area Surface WaterZone avgNot detected ng/L0% of limit Murrieta Service Area Surface WaterZone avgNot detected ng/L0% of limit Riverside Service Area Surface WaterZone avgNot detected ng/L0% of limit
PFOSPerfluorooctanesulfonic acid, a PFAS 'forever chemical' once used in firefighting foam and coatings.	Not detected ng/LAverageRiverside Service Area Local Groundwater	6.5 ng/LNL	Within the limit
+By source (5)— Murrieta Service Area Local Groundwater, Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water +2 more Murrieta Service Area Local GroundwaterZone avgNot detected ng/Lrange0–4.1 ng/L102% of limit Riverside Service Area Local GroundwaterZone avgNot detected ng/L0% of limit Murrieta Service Area Surface WaterZone avgNot detected ng/L0% of limit Rainbow Service Area Surface WaterZone avgNot detected ng/L0% of limit Riverside Service Area Surface WaterZone avgNot detected ng/L0% of limit
Perfluorobutanesulfonic acidPerfluorobutanesulfonic acid, a shorter-chain PFAS 'forever chemical.'	Not detected ng/LAverageMurrieta	500 ng/LNL	Detected — no federal limit
Perfluorohexanoic acidPerfluorohexanoic acid, a shorter-chain PFAS 'forever chemical.'	Not detected ng/LAverageRiverside Service Area Local Groundwater	None set	Detected — no federal limit
+By source (5)— Riverside Service Area Local Groundwater, Rainbow Service Area Surface Water, Murrieta Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avgNot detected ng/Lrange0–4.4 ng/L Rainbow Service Area Surface WaterZone avgNot detected ng/L Murrieta Service Area Surface WaterZone avgNot detected ng/L Riverside Service Area Surface WaterZone avgNot detected ng/L Murrieta Service Area Local GroundwaterZone avgNot detected ng/L
Perfluoropentanoic acidPerfluoropentanoic acid, a shorter-chain PFAS 'forever chemical.'	Not detected ng/LAverageMurrieta	None set	Detected — no federal limit
+By source (5)— Riverside Service Area Local Groundwater, Murrieta Service Area Surface Water, Riverside Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avgNot detected ng/Lrange0–8.1 ng/L Murrieta Service Area Surface WaterZone avgNot detected ng/L Riverside Service Area Surface WaterZone avgNot detected ng/L Murrieta Service Area Local GroundwaterZone avgNot detected ng/L Rainbow Service Area Surface WaterZone avgNot detected ng/L
PFBAPerfluorobutanoic acid, a shorter-chain PFAS 'forever chemical.'	Not detected ng/LAverageRiverside Service Area Surface Water	None set	Detected — no federal limit
+By source (5)— Riverside Service Area Local Groundwater, Riverside Service Area Surface Water, Murrieta Service Area Surface Water +2 more Riverside Service Area Local GroundwaterZone avgNot detected ng/Lrange0–5.4 ng/L Riverside Service Area Surface WaterZone avgNot detected ng/L Murrieta Service Area Surface WaterZone avgNot detected ng/L Rainbow Service Area Surface WaterZone avgNot detected ng/L Murrieta Service Area Local GroundwaterZone avgNot detected ng/L

Microbial

Contaminant	Measured	Federal limit	Status
Total ColiformA group of bacteria used as an indicator of overall water-system sanitation.	1AverageRiverside	None set	Detected — no federal limit

Source: Western MWD — Riverside, Ca, CA's 2023 Consumer Confidence Report — the annual drinking-water report every U.S. utility is required to publish. The numbers on this page are the utility's own. A water-quality report covers an entire service area, not a single address.