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San Luis Obispo Tap Water Quality Report
Limited testing on file — only PFAS results from EPA's UCMR 5 for SAN LUIS OBISPO WATER DEPARTMENT. No other contaminant results are on file for SAN LUIS OBISPO WATER DEPARTMENT; check its latest Consumer Confidence Report for its current test results.
Other systems listed for San Luis Obispo with results above guidelines: SLOCSA #10A - CAYUCOS (2 above guidelines)
Water system
SAN LUIS OBISPO WATER DEPARTMENT
3 other systems are listed for San Luis Obispo. See their figures
People Served
47,788
Health-based violations since 2020
0
SAN LUIS OBISPO WATER DEPARTMENT. EPA SDWA violation data as of Q2 2026 (downloaded 2026-07-09).
Latest sample on file
May 2024 · SAN LUIS OBISPO WATER DEPARTMENT
Utilities publish newer results in their annual water quality report (Consumer Confidence Report).
Is San Luis Obispo Tap Water Safe to Drink?
Only PFAS results from EPA's UCMR 5 are on file for San Luis Obispo's own water system, so everything else listed below has no result behind it. Testing your own water is the way to find out what your tap is actually delivering.
SAN LUIS OBISPO WATER DEPARTMENT, San Luis Obispo's water system, serves 47,788 people. 3 other systems are listed for San Luis Obispo. Each system's results are listed under its own name, never added to SAN LUIS OBISPO WATER DEPARTMENT's. Water quality testing is conducted regularly and reported to the EPA. The latest sample on file for SAN LUIS OBISPO WATER DEPARTMENT is from May 2024.
Boil water advisories are issued by water systems and state agencies, and they change from day to day. Boil water advisories in California
San Luis Obispo Water Service Areas
What these numbers actually mean for San Luis Obispo, CA
We read San Luis Obispo, CA’s published record and send you a short report — which findings warrant a decision, which to ignore, and what to do about it. Including when the answer is nothing.
- 23 contaminants listed, only PFAS results from EPA's UCMR 5 on file
- 23 PFAS compounds on record
Buying a home here? Property Water Report — $49 Emailed within one business day.
Fluoride in San Luis Obispo's water
SAN LUIS OBISPO WATER DEPARTMENT
PWSID CA4010009
No fluoride level in our data for SAN LUIS OBISPO WATER DEPARTMENT. Your utility's annual water quality report (CCR) lists it.
SLOCSA #10A - CAYUCOS
PWSID CA4010901
No fluoride level in our data for SLOCSA #10A - CAYUCOS. Your utility's annual water quality report (CCR) lists it.
CALLENDER GROVE MUTUAL WATER
PWSID CA4000805
No fluoride level in our data for CALLENDER GROVE MUTUAL WATER. Your utility's annual water quality report (CCR) lists it.
SLO CWD NO. 10 - CAYUCOS WTP
PWSID CA4010025
SLO CWD NO. 10 - CAYUCOS WTP reported 0.307 mg/L, below the 0.7 mg/L U.S. Public Health Service recommendation.
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General-Purpose Water Filters for San Luis Obispo
San Luis Obispo's results show no result above EPA's health goals or legal limits, so these are general-purpose NSF/ANSI 53 certified filters, not chosen for any contaminant.
Pentair Residential Filtration, LLC
Everpure Residential H-300-NXT
NSF Certified:
Capacity
3001 gal
Filter Life
10 mo
Flow Rate
0.5 gpm
Removes 5 contaminants:
Whirlpool Corporation
W11256135
NSF Certified:
Capacity
1001 gal
Filter Life
3 mo
Flow Rate
0.7 gpm
Removes 19 contaminants:
+14 more
Benzene, Carbofuran, Chlorine (Free), Chlorine (Total), Chlorine Dioxide, Chlorobenzene, Cryptosporidium, Ethylbenzene, Lead, Mercury, Metolachlor, Tetrachloroethylene, Toxaphene, Turbidity
Whirlpool Corporation
W11569861
NSF Certified:
Capacity
1001 gal
Filter Life
3 mo
Flow Rate
0.52 gpm
Removes 22 contaminants:
+17 more
Atrazine, Benzene, Carbofuran, Chlorine (Free), Chlorine (Total), Chlorine Dioxide, Chlorobenzene, Cryptosporidium, Ethylbenzene, Lead, Mercury, Metolachlor, Styrene, Tetrachloroethylene, Toxaphene, Trichloroethylene, Turbidity
Santevia
Bath Filter
NSF Certified:
Flow Rate
0.36 gpm
Highlights:
- Organic cotton design reduces plastic used in construction
- Affordable upfront & ongoing cost
- The only bath filter that removed 100% chlorine with “normal” faster faucet flow
Removes 1 contaminants:
Test Your Water Quality
Professional laboratory testing provides accurate, detailed analysis of your drinking water.
SimpleLab
Advanced Home Water Test
$269
Comprehensive water analysis testing over 200 contaminants including bacteria, heavy metals, and chemical compounds.
Tap Score
Advanced Microplastics Test
$829
Cutting-edge testing for microplastics particles in drinking water using advanced laboratory techniques.
Tap Score
Haloacetic Acids (HAA9) Test
$275
Tests for disinfection byproducts formed when chlorine reacts with organic matter in water treatment.
What San Luis Obispo's water readings can explain
We publish a city-level hardness figure for San Luis Obispo, resolved from its water systems where they report one and estimated from county sampling where they do not. Each page starts with the hot-tap and cold-tap check, then shows what your own water system reported.
On a private well near San Luis Obispo? Public-water results do not apply to private wells. See San Luis Obispo County well water testing and USGS risk data — modeled arsenic, nitrate, and the tests to run.
Water softener cost and installation in San Luis Obispo
San Luis Obispo's tap water has an estimated 27.5 grains per gallon (470.0 mg/L, county sampling in San Luis Obispo County) — very hard on the USGS scale, the range where scale on fixtures and appliances is the usual complaint.
Water softener cost for an estimated 27.5 gpg water in San Luis Obispo — equipment and local installation labour for your ZIP code, with the sizing arithmetic shown in full. For the national picture first, read what a water softener costs — equipment, installation labour and ten-year ownership, each separated out. For California as a whole, read water softener cost in California — priced against the plumber wage published for the state.
Frequently Asked Questions About San Luis Obispo Tap Water
Limited testing on file — only PFAS results from EPA's UCMR 5 for SAN LUIS OBISPO WATER DEPARTMENT. No other contaminant results are on file for SAN LUIS OBISPO WATER DEPARTMENT; check its latest Consumer Confidence Report for its current test results.
Spotted something off on this page?
Residents keep our data honest.
This form corrects our data; it does not reach SAN LUIS OBISPO WATER DEPARTMENT. For a problem with your water now (discolored water, no water, low pressure, a leak), contact SAN LUIS OBISPO WATER DEPARTMENT directly.
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