EPA EXPORT · 13 SEP 2026FEDERAL COMPLIANCE RECORDS · NOT A HOME WATER TEST
TAP WATERLEDGERPublic system compliance records

COUNTY WATER-SYSTEM LEDGER

San Luis Obispo, California

Compare active community water systems serving this county in EPA's public export. Systems can serve multiple places, so population totals may overlap.

Systems20active CWS · pop. 2,500+
Population served245,555reported total; may overlap
Current violation flag0.0%0 systems
Serious-violator flag0.0%0 systems

01 / SYSTEMS

Water systems serving San Luis Obispo

Ordered by reported population served. Open any record for separate health, monitoring, notice, other, and serious-violator flags.

Water systemPopulation servedPrimary sourceCurrent export status
San Luis Obispo Water DepartmentCA401000947,788Surface waterNo current violation flagged
City Of Paso Robles Water DivisionCA401000731,176Surface waterNo current violation flagged
Atascadero Mutual Water CoCA401000230,618Ground waterNo current violation flagged
City Of Arroyo Grande Utilities DivisionCA401000117,963Surface water purchasedNo current violation flagged
California Mens ColonyCA401083015,000Surface waterNo current violation flagged
Nipomo Comm Services DistCA401002613,771Surface water purchasedNo current violation flagged
Morro Bay Pw Dept - Water DivisionCA401001113,757Surface water purchasedNo current violation flagged
City Of Grover Beach Public Works DeptCA401000412,701Surface waterNo current violation flagged
Pismo Beach Water DepartmentCA40100088,036Surface water purchasedNo current violation flagged
Templeton CsdCA40100198,011Ground waterNo current violation flagged
Oceano Comm Services Dist.CA40100057,601Surface water purchasedNo current violation flagged
Los Osos Community Services DistrictCA40100167,086Ground waterNo current violation flagged
Golden State Water Company - Los OsosCA40100175,924Ground waterNo current violation flagged
Cambria Comm Services DistCA40100145,532Ground waterNo current violation flagged
Golden State Water Company - NipomoCA40100184,506Surface water purchasedNo current violation flagged
Atascadero State HospitalCA40108324,100Ground waterNo current violation flagged
Woodlands DevelopmentCA40100813,862Surface water purchasedNo current violation flagged
Heritage Ranch CsdCA40100122,956Surface waterNo current violation flagged
San Miguel Community Services DistrictCA40100102,600Ground waterNo current violation flagged
Cayucos Beach Mutual Water CompanyCA40100062,567Surface water purchasedNo current violation flagged

02 / SOURCE MIX

Surface water5 systems · 109,621 served
Surface water purchased8 systems · 72,063 served
Ground water7 systems · 63,871 served
How to read the population total

It is the sum of each listed system's reported population served, not a census estimate. Service areas can overlap and some systems list multiple cities or counties.