Water utility
Where Santa Rosa’s water comes from
Utility City of Santa Rosa
Water system SANTA ROSA, CITY OF · CA4910009
Source water Groundwater
Disinfectant not on record
Population served 178,452
Reporting period Sampled 2023–2025
Monitoring coverage 32 records · 3 of 4 groups measured Listed match EPA lists this system for the city. Your water bill or annual water quality report names your actual supplier. Source: EPA SDWIS 2026Q2.
CA4910009 · 178,452 served 98 /100 · Excellent Confidence: moderate
Why this matters 1 2 Treatment The treatment details are not on record.
3 Distribution Mains, then your building’s service line.
4 Your tap Plumbing inside the building is outside this record.
At a glance
Santa Rosa water in four numbers 98 /100 · Excellent Confidence: moderate Purity Score SANTA ROSA, CITY OF · PWSID CA4910009
3 Detected 1 above a reference
1 Above a reference of 32 records
0 Health-based violations last 10 years · EPA SDWIS
No measured result is above a legal limit; lithium sits above a screening level, and the water is moderately hard.
What we found
3 detected results, by distance from their limit ? Each bar runs to the named reference; the tick marks it. Open a row for five layers: measured, compared, meaning, where it matters, what to do. Li Lithium Above screening · Screening level 10 µg/L EPA health reference level (screening, not a legal limit) 96 µg/L ▾ ① · Measured 96 µg/L, sampled 2024-05-09 to 2024-11-05. EPA UCMR 5.
② · Compared 10 µg/L EPA health reference level (screening, not a legal limit).
③ · Meaning Detected at up to 96 µg/L (above the 10 µg/L EPA health reference level; a screening level, not a legal limit).
④ · Where it matters Where it enters is not in this record.
⑤ · What to do Test your own tap first. To reduce it: Depends on the contaminant (The certifier's listing for each named contaminant).
See the evidence record → Pb Lead (90th percentile) Within reference · Action level 15 µg/L federal action level 1.32 µg/L ▾ ① · Measured 1.32 µg/L, sampled 2023–2025 monitoring period. EPA SDWIS (Lead & Copper Rule).
② · Compared 15 µg/L federal action level. EPA health goal (MCLG): 0.
③ · Meaning The 90th-percentile tap result was 1.32 µg/L (below the 15 µg/L action level).
④ · Where it matters Usually from lead service lines, solder and fixtures inside buildings, after the water leaves treatment.
⑤ · What to do Test your own tap first. To reduce it: Lead-certified carbon filter, or reverse osmosis (NSF/ANSI 53 (lead)).
See the evidence record → Hard Water hardness Within reference · Aesthetic, no health limit Aesthetic, no federal health limit 6.5 gpg ▾ ① · Measured 6.5 gpg, sampled 2025. Utility CCR.
② · Compared Aesthetic, no federal health limit.
③ · Meaning 112 mg/L as CaCO3 (6.5 grains/gal), moderately hard. Aesthetic (scale/appliances), not a health finding.
④ · Where it matters Shows up as scale in kettles, water heaters and fixtures.
⑤ · What to do Test your own tap first. Technologies that can reduce it: Ion-exchange water softener, Salt-free conditioner, Reverse osmosis (point-of-use).
See the evidence record → 29 others tested , none detectedshow 11Cl-PF3OUdS 8:2 FTS 4:2 FTS 6:2 FTS ADONA 9Cl-PF3ONS HFPO-DA (GenX) NEtFOSAA NMeFOSAA NFDHA PFEESA PFMPA PFMBA PFBS PFBA PFDA PFDoA PFHpS PFHpA PFHxS PFHxA PFNA PFOS PFOA PFPeS PFPeA PFTA PFTrDA PFUnA SANTA ROSA, CITY OF (EPA PWSID CA4910009) delivers groundwater to 178,452 residents. This report reflects 29 individual PFAS result(s) from the source UCMR5 observations and the latest Lead & Copper Rule 90th-percentile result. The utility's 2025 CCR reports moderately hard water.
Track record 0 health-based violations in the last 10 years
From EPA SDWIS. A clean violation history means no enforcement action was recorded; it does not cover contaminants without a limit.
Not in this record Disinfection by-products weren't monitored in this dataset No result is not a pass. Your utility's annual water quality report may list them, and a certified lab test covers your own tap.
Your household Your tap can differ from the city record The record describes water leaving treatment and samples across the system. Pipes, solder and fixtures inside a building can add lead the record can’t see, especially in older buildings with lead service lines.
Test your water City Treated water Measured in this report
Mains Distribution network Sampled across the system
Building Service line and plumbing Not in this record
Tap Your glass Only a tap test measures it
Test first, then treat
Three steps from a record to your glass
01 Test Know what comes from your tap, starting with a first-draw lead sample.
02 Match Compare each result with its named reference in our test reader .
03 Treat Choose a technology certified for what your test found.
Commercial
Test kits Affiliate links ? As an Amazon Associate, PurityMap earns from qualifying purchases. Screening tells you if something is worth a closer look; a lab result is the number you can act on.
As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure .
Lab-certified results
ETR Labs Basic Water Quality Test Kit ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
Screening: quick check, not lab-grade
Safe Home DIY Lead in Drinking Water Combo Test Kit Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
When your results arrive, read them here → · Compare every kit we list
Treatment matching
What can reduce what was found here ? Finding → technology → certification → product, in that order. The reference type carries the meaning; there is no severity score. Finding Reference type Technology Certification to check Lithium 96 µg/L Screening level Depends on the contaminant The certifier's listing for each named contaminant Lead (90th percentile) 1.32 µg/L Action level Lead-certified carbon filter, or reverse osmosis NSF/ANSI 53 (lead) Water hardness 6.5 gpg Aesthetic, no health limit Ion-exchange water softener, Salt-free conditioner, Reverse osmosis (point-of-use) Check the certifier’s listing
Understand water treatment technologies →
Commercial Certified for a concern found here Each card names which Santa Rosa findings its current certification covers, and which it doesn't.
As an Amazon Associate, PurityMap earns from qualifying purchases. A product appears here only when a current certification record covers at least one identified concern; every concern stays listed. The retail offer is looked up afterwards and never changes which products appear or their order. Affiliate disclosure .
Water Pitcher
Brita Elite Water Filter Pitcher ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Water Pitcher
Culligan ZeroWater 10-Cup Pitcher (ZEROP10) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names See all 13 products certified for a Santa Rosa concern → Faucet Attachment
PUR Plus Faucet Filter (FM2500V) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Under-Sink Filter
Aquasana Claryum 2-Stage Under-Sink Filter (AQ-5200) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (5) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Anyone who can't plumb, drill or hire an installer Renters who can't modify plumbing Under-Sink Filter
Aquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (5) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Anyone who can't plumb, drill or hire an installer Renters who can't modify plumbing Countertop System
Aquasana Clean Water Machine Countertop Filter (AQ-CWM2) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Under-Sink Filter
Frizzlife SP99 Under-Sink Filter ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (4) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Anyone who can't plumb, drill or hire an installer Countertop System
Patriot Pure Ultimate Water Filtration System ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Countertop System
AquaTru Carafe Countertop Reverse-Osmosis Purifier (AT100) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Countertop System
AquaTru Classic Countertop Reverse-Osmosis Purifier (AT2000) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Under-Sink Filter
Waterdrop G3P600 Tankless Reverse-Osmosis System ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (5) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Anyone who can't plumb, drill or hire an installer Renters who can't modify plumbing Under-Sink Filter
Waterdrop G3P800 Tankless Reverse-Osmosis System ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (5) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Anyone who can't plumb, drill or hire an installer Renters who can't modify plumbing Refrigerator Filter
Whirlpool Filter 3 Refrigerator Water Filter (WHR3RXD1) ✓ Lead: eligible, evidence match – Not established: LithiumNot suitable for (3) Treating every tap in the home A whole-home hard-water or scale problem All PFAS: its evidence covers only the compounds it names Ask your utility first
Find out if your building has a lead service line Water utilities keep an inventory of service-line materials. Ask City of Santa Rosa whether your address is on it before you replace pipes.
Local help
Think your plumbing may be adding lead? Call to be connected with a local plumbing provider about lead service lines, repiping or fixture replacement.
Is this right for my home?
Choose your situation Your situation I live in an older building I care about PFAS My water tastes of chlorine I have scale or hard water I want the broadest reduction
Your path: I live in an older building Lead from plumbing is the main question Older buildings may have lead service lines, solder or fixtures. Santa Rosa’s record shows lead at 1.32 µg/L (15 µg/L federal action level). Test first-draw water, then filter if needed.
Look for Lead reduction: NSF/ANSI 53 (lead)
How to test your tap →
Your path: I care about PFAS Check what was tested None of the 29 PFAS tested was detected in Santa Rosa’s record. If PFAS matters to you, a filter certification names each compound it covers.
Look for NSF/ANSI 53 or 58, with each compound you care about named on the listing
PFAS in Santa Rosa →
Your path: My water tastes of chlorine The disinfectant is not in this record Most utilities keep chlorine or chloramine in the pipes. A carbon filter certified for taste and odor reduces either; your utility can tell you which it uses.
Look for NSF/ANSI 42 (chlorine taste and odor)
Water treatment technologies →
Your path: I have scale or hard water Santa Rosa water is moderately hard (6.5 gpg) Scale is a comfort and appliance issue, not a health one.
Look for Softener: NSF/ANSI 44 (softeners)
Hard water in Santa Rosa →
Your path: I want the broadest reduction Reverse osmosis at one tap Reverse osmosis reduces many dissolved contaminants, including lead and minerals, at a single faucet, with some water sent to drain.
Look for NSF/ANSI 58
Compare treatments → Questions
Santa Rosa tap water FAQ Follow Santa Rosa’s water
Get one email when Santa Rosa’s record changes.
? One email when a new sampling round is published, a result moves above or below its reference, or the system's score changes. Follow Santa Rosa’s water → Is Santa Rosa tap water safe to drink? + PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For Santa Rosa, no regulated PFAS were detected in EPA's 2024 testing; the lead 90th-percentile result was 1.32 µg/L against the 15 µg/L action level. SANTA ROSA, CITY OF (PWSID CA4910009) has a Purity Score of 98/100 (confidence: moderate), assessed at the water-system level and computed only from contaminants that were measured. Water can change in your own pipes, so a certified test is the only way to know what comes out of your tap. What we found →
Who provides tap water in Santa Rosa? + SANTA ROSA, CITY OF (PWS ID CA4910009) is the public water system on record for Santa Rosa, California, serving about 178,452 people. Confirm the utility on your water bill before acting on a specific finding. Water utility →
Where does Santa Rosa get its drinking water? + Groundwater (primary source of record in EPA SDWIS). Water utility →
Are PFAS "forever chemicals" in Santa Rosa's water? + None of the 29 PFAS in EPA's UCMR 5 testing (2024-05-09 to 2024-12-04) was detected. "Not detected" means below the lab's reporting limit, not proven zero. What we found →
Is there lead in Santa Rosa's tap water? + SANTA ROSA, CITY OF's most recent lead 90th-percentile result (2023–2025) was 1.32 µg/L, below the 15 µg/L action level. That figure comes from sampled homes; lead usually enters from a building's own pipes and fixtures, so only a test at your tap tells you what you drink. Your household →
What does the latest Santa Rosa water report show? + PurityMap's current record for Santa Rosa holds 32 findings: 1 above a reference, 2 detected within the reference and 29 not detected. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass. Records →
Is Santa Rosa's water hard? + Santa Rosa's water is recorded as 6.5 gpg, moderately hard. Hardness is an aesthetic and plumbing characteristic, not a health-based limit. Choose your situation →
Data and sources
32 records, each traceable EPA UCMR 5 EPA SDWIS (Lead & Copper Rule) Utility CCR Contaminant Measured Reference Sampled Source Lithium 96 µg/L 10 µg/L EPA health reference level (screening, not a legal limit) 2024 EPA UCMR 5 ↗ (opens in a new tab) Lead (90th percentile) 1.32 µg/L 15 µg/L federal action level 2023–2025 EPA SDWIS (Lead & Copper Rule) ↗ (opens in a new tab) Water hardness 6.5 gpg Aesthetic, no federal health limit 2025 Utility CCR ↗ (opens in a new tab) 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) < 5 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) < 5 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) < 5 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) < 2 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) < 5 ng/L (not detected) 10 ng/L federal MCL (2024) 2024 EPA UCMR 5 ↗ (opens in a new tab) N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) < 5 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) < 6 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) < 20 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoro-3-methoxypropanoic acid (PFMPA) < 4 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoro-4-methoxybutanoic acid (PFMBA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorobutanesulfonic acid (PFBS) < 3 ng/L (not detected) 2,000 ng/L EPA health advisory (screening, not a legal limit) 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorobutanoic acid (PFBA) < 5 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorodecanoic acid (PFDA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorododecanoic acid (PFDoA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoroheptanesulfonic acid (PFHpS) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoroheptanoic acid (PFHpA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorohexanesulfonic acid (PFHxS) < 3 ng/L (not detected) 10 ng/L federal MCL (2024) 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorohexanoic acid (PFHxA) < 3 ng/L (not detected) 400,000 ng/L Michigan EGLE state MCL (strictest US state) 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorononanoic acid (PFNA) < 4 ng/L (not detected) 10 ng/L federal MCL (2024) 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorooctanesulfonic acid (PFOS) < 4 ng/L (not detected) 4.0 ng/L federal MCL (2024) 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorooctanoic acid (PFOA) < 4 ng/L (not detected) 4.0 ng/L federal MCL (2024) 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoropentanesulfonic acid (PFPeS) < 4 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoropentanoic acid (PFPeA) < 3 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorotetradecanoic acid (PFTA) < 8 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluorotridecanoic acid (PFTrDA) < 7 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab) Perfluoroundecanoic acid (PFUnA) < 2 ng/L (not detected) No federal or state limit; shown for transparency 2024 EPA UCMR 5 ↗ (opens in a new tab)
Showing 5 of 32 records Show all 32 ▾ Show fewer ▴ UCMR5 Analytical Results
UCMR5 Analytical Results: SANTA ROSA, CITY OF (CA4910009)
US EPA
Published 2026-10-15 Newest sample 2024-12-04 Findings here 30 View source ↗ Source record
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: SANTA ROSA, CITY OF (CA4910009)
US EPA SDWIS
Published 2026-10-13 Newest sample 2025 Findings here 1 View source ↗ Source record
Consumer Confidence Report (CCR)
Santa Rosa Water (City of Santa Rosa) 2025 Consumer Confidence Report (CCR)
Santa Rosa Water (City of Santa Rosa)
Published 2025-01-01 Newest sample 2025 Findings here 1 View source ↗ Source record
Methodology: how we analyze water . Prepared with AI assistance and reviewed by the PurityMap Editorial Team before publication.
Methodology
How PurityMap reads Santa Rosa’s water 01 Source data EPA SDWIS, EPA UCMR 5 and utility reports, each dated and linked.
02 Normalize Units converted to one basis; a non-detect kept distinct from zero.
03 Classify Each result tagged by reference type: MCL, action level, screening level or aesthetic.
04 Compare to the named reference Every value sits against its own reference, never a blended one.
05 Score Measured subjects summarised at the water-system level; an open health-based violation caps the score.
06 Match treatment Treatment is matched to what was found; a product is called certified only when its current certification names it.
What the Purity Score means: a summary of this water system’s published record, capped while a health-based violation is open. It is not a test of any tap. SANTA ROSA, CITY OF · PWSID CA4910009 · Purity Score 98/100 (Excellent) · Confidence: moderate · Assessed at the water-system level
Full methodology → Something off with your water's smell, color or taste? Start with the hot-or-cold tap check. Where City of Santa Rosa reported something related, it's shown below.
More Santa Rosa water intelligence Nearby city reports