Your Local Water Profile: Hermosa Beach
This profile explains what the applicable water provider reported for Hermosa Beach, what those results may mean throughout a home, and where property-specific testing or inspection may still be needed.
Water provider: Rancho Dominguez DISTRICT Hermosa-Redondo System
Public water system CA1910134 · 2025 report · Current 2025 monitoring cycle
View the 2025 Rancho Dominguez DISTRICT Hermosa-Redondo System Consumer Confidence ReportWhat the official water report says
Your water at a glance
California Water Service
The report lists hardness as 502 ppm; 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.
Rancho Dominguez DISTRICT Hermosa-Redondo System — compliance, as reported
The report states: “WE ARE PLEASED TO CONFIRM THAT WE MET EVERY PRIMARY AND SECONDARY FEDERAL AND STATE WATER QUALITY STANDARD LAST YEAR. [p. 3]”
Violations or advisories, as reported: In one sample in the Hermosa-Redondo system, “color, apparent” exceeded the SMCL of 15 CU. Compliance with the SMCL is based on a RAA and the RAA is less then the SMCL. We are monitoring the levels to confirm we do not exceed the SMCL RAA. The SMCL was set to protect you against unpleasant aesthetic effects, such as color, taste, odor, and the staining of plumbing fixtures and clothing when washed. Exceeding the SMCL does not pose a health risk. [p. 14]
The Three C's — 1 of 3
Chemistry
What does this water tend to do in a home?
Alkalinity (total)
The utility reported: 150 ppm
UNREGULATED COMPOUNDS · report p. 14 · official report
Total dissolved solids
The utility reported: 642 ppm
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Sulfate
The utility reported: 147 ppm
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Lead
The utility reported: Not detected at the report's stated reporting limit ppb
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Copper
The utility reported: 0.10 ppm
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Total chlorine
The utility reported: 2.1 ppm
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Hardness (total)
The utility reported: 236 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Calcium
The utility reported: 56 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Magnesium
The utility reported: 22 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
pH
The utility reported: 8.3 Units
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Alkalinity (total)
The utility reported: 108 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Total dissolved solids, filterable (TDS)
The utility reported: 545 ppm
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Chloride
The utility reported: 92 ppm
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Sulfate
The utility reported: 182 ppm
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Sodium
The utility reported: 88 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Calcium carbonate precipitation potential (CCPP)
The utility reported: 7.4 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Corrosivity (as aggressiveness index)
The utility reported: 12.4 AI
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Corrosivity (as saturation index)
The utility reported: 0.58 SI
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
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.
Rancho Dominguez DISTRICT Hermosa-Redondo System — regulated contaminants reported as detected (20)
Barium
The utility reported: 0.24 ppm
Reported range: 0.23-0.25
Legal limit (MCL): 1 · Health goal (PHG): 2 — not an enforceable limit
Violation per report: No
Typical source, per the report: ER, OD
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Fluoride
The utility reported: 0.60 ppm
Reported range: 0.24-0.73
Legal limit (MCL): 2 · Health goal (PHG): 1 — not an enforceable limit
Violation per report: No
Typical source, per the report: ER, FL
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Copper
The utility reported: 0.10 ppm
AL: 1.3 · Health goal (PHG): 0.3 — not an enforceable limit
Violation per report: No
Typical source, per the report: IC, ER, WD
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Total haloacetic acids (THAA)
The utility reported: 10 ppb
Reported range: 5.8-13
Legal limit (MCL): 60
Violation per report: No
Typical source, per the report: DI
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Total trihalomethane (TTHM)
The utility reported: 35 ppb
Reported range: 26-41
Legal limit (MCL): 80
Violation per report: No
Typical source, per the report: DI
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Total chlorine
The utility reported: 2.1 ppm
Reported range: 0.33-3.3
MRDL: 4 · Health goal (MRDLG): 4 — not an enforceable limit
Violation per report: No
Typical source, per the report: DS
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Combined filter effluent (CFE) turbidity
The utility reported: 0.05 NTU
TT: TT
Violation per report: No
Typical source, per the report: SO
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · official report
Total coliform bacteria
The utility reported: 0.08 %
Reported range: 0-0.5
TT: TT · Health goal (PHG): 0 — not an enforceable limit
Violation per report: No
Typical source, per the report: FE
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · 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 (PHG): 0 — not an enforceable limit
Violation per report: No
Typical source, per the report: ER
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · 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 (PHG): 0 — not an enforceable limit
Violation per report: No
Typical source, per the report: DK
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · official report
Radium-228
The utility reported: Not detected at the report's stated reporting limit pCi/L
Reported range: ND-1
Violation per report: No
Typical source, per the report: ER
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · official report
Combined radium-226 + 228
The utility reported: Not detected at the report's stated reporting limit pCi/L
Reported range: ND-1
Legal limit (MCL): 5 · Health goal (PHG): 0 — not an enforceable limit
Violation per report: No
Typical source, per the report: ER
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · official report
Uranium
The utility reported: 2 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: ER
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · official report
Aluminum
The utility reported: 0.096 ppm
Reported range: ND-0.12
Legal limit (MCL): 1 · Health goal (PHG): 0.6 — not an enforceable limit
Violation per report: No
Typical source, per the report: ER
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · 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: ER, OD
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · official report
Fluoride
The utility reported: 0.7 ppm
Reported range: 0.2-0.9
Legal limit (MCL): 2 · Health goal (PHG): 1 — not an enforceable limit
Violation per report: No
Typical source, per the report: ER, FL
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · official report
Total trihalomethane (TTHM)
The utility reported: 33 ppb
Reported range: 9.8-55
Legal limit (MCL): 80
Violation per report: No
Typical source, per the report: DI
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · official report
Sum of five haloacetic acids (HAA5)
The utility reported: 9.4 ppb
Reported range: ND-18
Legal limit (MCL): 60
Violation per report: No
Typical source, per the report: DI
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · official report
Bromate
The utility reported: 4.1 ppb
Reported range: ND-12
Legal limit (MCL): 10 · Health goal (PHG): 0.1 — not an enforceable limit
Violation per report: No
Typical source, per the report: DI
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · official report
Total organic carbon (TOC)
The utility reported: 2.6 ppm
Reported range: 1.5-2.9
TT: TT
Violation per report: No
Typical source, per the report: VA
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 16 · official report
Rancho Dominguez DISTRICT Hermosa-Redondo System — unregulated monitoring and secondary (aesthetic) records (15)
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, apparent
The utility reported: Not detected at the report's stated reporting limit CU
Reported range: ND-35
Typical source, per the report: OM
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Manganese
The utility reported: Not detected at the report's stated reporting limit ppb
Reported range: ND-24
Typical source, per the report: RU
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Odor
The utility reported: Not detected at the report's stated reporting limit T.O.N.
Reported range: ND-2.0
Typical source, per the report: OM
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Turbidity (groundwater)
The utility reported: 0.23 NTU
Reported range: 0.10-4.3
Typical source, per the report: SO
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Boron
The utility reported: 0.14 ppm
Reported range: 0.13-0.15
Typical source, per the report: UR
STATE-REGULATED CONTAMINANTS WITH NOTIFICATION LEVELS · report p. 14 · official report
Potassium
The utility reported: 8.2 ppm
Reported range: 7.8-8.5
Typical source, per the report: UR
UNREGULATED COMPOUNDS · report p. 14 · official report
Lithium
The utility reported: 9.6 ppb
Reported range: 9.6
Typical source, per the report: UR
UNREGULATED COMPOUNDS · report p. 14 · official report
Aluminum
The utility reported: 96 ppb
Reported range: ND-120
Typical source, per the report: RU, SW
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Color
The utility reported: 1 UNITS
Reported range: 1
Typical source, per the report: OM
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Specific conductance
The utility reported: 873 µS/cm
Reported range: 386-987
Typical source, per the report: SW, IO
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Boron
The utility reported: 0.19 ppm
Reported range: 0.12-0.19
Typical source, per the report: UR
WHOLESALER DATA - STATE-REGULATED CONTAMINANTS WITH NOTIFICATION LEVELS · report p. 17 · official report
Chlorate
The utility reported: 32 ppb
Reported range: ND-32
Typical source, per the report: UR
WHOLESALER DATA - STATE-REGULATED CONTAMINANTS WITH NOTIFICATION LEVELS · report p. 17 · official report
N-nitrosodimethylamine (NDMA)
The utility reported: 2.1 ppt
Reported range: ND-2.8
Typical source, per the report: UR
WHOLESALER DATA - STATE-REGULATED CONTAMINANTS WITH NOTIFICATION LEVELS · report p. 17 · official report
Lithium
The utility reported: 35 ppb
Reported range: ND-42
Typical source, per the report: UR
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Potassium
The utility reported: 4.4 ppm
Reported range: 2.3-5
Typical source, per the report: UR
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
The Three C's — 3 of 3
Corrosion
What conditions could influence pipes, fixtures, and a water heater?
Alkalinity (total)
The utility reported: 150 ppm
UNREGULATED COMPOUNDS · report p. 14 · official report
Sulfate
The utility reported: 147 ppm
SECONDARY DRINKING WATER STANDARDS · report p. 14 · official report
Lead
The utility reported: Not detected at the report's stated reporting limit ppb
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
Copper
The utility reported: 0.10 ppm
PRIMARY DRINKING WATER STANDARDS · report p. 13 · official report
pH
The utility reported: 8.3 Units
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Alkalinity (total)
The utility reported: 108 ppm
WHOLESALER DATA - UNREGULATED COMPOUNDS · report p. 18 · official report
Chloride
The utility reported: 92 ppm
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Sulfate
The utility reported: 182 ppm
WHOLESALER DATA - SECONDARY DRINKING WATER STANDARDS · report p. 17 · official report
Gross alpha particle activity
The utility reported: Not detected at the report's stated reporting limit pCi/L
Reported range: ND-5
Typical source, per the report: ER
WHOLESALER DATA - PRIMARY DRINKING WATER STANDARDS · report p. 15 · official report
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:
- 1Define the concern
- 2Verify utility-level and home-specific evidence
- 3Choose point of treatment
- 4Verify the exact certified reduction claim for the exact model
- 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 — Rancho Dominguez DISTRICT Hermosa-Redondo System
2025 WATER QUALITY REPORT Rancho Dominguez DISTRICT Hermosa-Redondo System · data year 2025 · Current 2025 monitoring cycle
View the 2025 Rancho Dominguez DISTRICT Hermosa-Redondo System Consumer Confidence ReportSource water, per the report: To meet our customers’ needs, we use a combination of local groundwater and surface water purchased from Metropolitan Water District of Southern California (MWD), which is obtained from the Colorado River and the State Water Project in northern California.
Nearby community water profiles
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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