Public water system · CA4000800
ActivePort San Luis Harbor District
At a glance
Port San Luis Harbor District (PWSID CA4000800) is an active non-transient non-community water system in San Luis Obispo County, California. It reports serving 125 people through 38 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's Safe Drinking Water Act records list no violations for this system.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
125
Service connections
38
Primary source
SWP
Purchased surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Port San Luis Harbor District compare with other water systems in San Luis Obispo County?
By EPA's size categories, Port San Luis Harbor District is a very small system (500 people or fewer). San Luis Obispo County has 171 active public water systems. Its population served is well below the county average of 2,038 people per system, and accounts for less than 0.1% of the 348,510 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Port San Luis Harbor District is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. California has 1,466 active non-transient non-community water systems, 20% of the state's 7,479 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 506 California systems (6.8%) list purchased surface water as their primary source.
Who owns and regulates Port San Luis Harbor District?
EPA lists Port San Luis Harbor District as owned by a local government. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 33 of the 171 active systems in San Luis Obispo County (19%) are also owned by a local government.
Does Port San Luis Harbor District have drinking water violations?
No SDWA violations on record.
EPA's SDWA violation and enforcement data (via EPA ECHO, updated quarterly) lists no violations for Port San Luis Harbor District. For the latest compliance status, check EPA ECHO for current compliance history.
Port San Luis Harbor District: frequently asked questions
Who runs Port San Luis Harbor District?
Port San Luis Harbor District (PWSID CA4000800) is a non-transient non-community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Port San Luis Harbor District serve?
Port San Luis Harbor District reports serving 125 people through 38 service connections in San Luis Obispo County, California.
Where does Port San Luis Harbor District get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Port San Luis Harbor District have any drinking water violations?
EPA's Safe Drinking Water Act records list no violations for this system.
Is Port San Luis Harbor District's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's Safe Drinking Water Act records list no violations for this system. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Port San Luis Harbor District's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Port San Luis Harbor District is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in San Luis Obispo County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Margarita Recreation Area | San Luis Obispo | 50,001 | Transient non-community | Groundwater |
| San Luis Obispo Water Department | San Luis Obispo | 47,788 | Community | Surface water |
| City of Paso Robles Water Division | San Luis Obispo | 31,176 | Community | Surface water |
| Atascadero Mutual Water Co | San Luis Obispo | 30,618 | Community | Groundwater |
| City of Arroyo Grande Utilities Division | San Luis Obispo | 17,963 | Community | Purchased surface water |
| California Mens Colony | San Luis Obispo | 15,000 | Community | Surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Port San Luis Harbor District, PWSID CA4000800, California”, https://aquacensus.com/water-systems/california/port-san-luis-harbor-district-ca4000800 (data as of October 1, 2026).