San Luis Opispo City WRRF

Active WDID 3 40I000455 San Luis Obispo, San Luis Obispo County Region 3 · Central Coast

At a glance

Permit Evidence: SMARTS record
Active Industrial
Notice of Intent (WDID code I) · Permits and applications
Location Evidence: facility-reported
San Luis Obispo, San Luis Obispo County
Region 3 · Central Coast · Location · Statewide map
Receiving water
San Luis Obispo Creek (as reported by the facility)
Evidence: candidate, awaiting review Details
Identified receiving water on the 2026 303(d) list
Not established
Shown only when the reported receiving water is identified and corroborated.
2026 Integrated Report waters within 1.0 km Evidence: geographic proximity
2 waterbodies; 2 on the 2026 303(d) list
Proximity only; not a discharge pathway · Nearby waterbodies
Monitoring results Evidence: facility-reported
214 distinct results, 8 reporting years (2015 to 2025)
Most recent sample Feb 16, 2026 · Monitoring
Compliance and enforcement records Evidence: SMARTS record
0 inspections · 2 violation records · 0 enforcement actions
Counts as published in SMARTS; not a compliance determination · Details
SMARTS TMDL records Evidence: SMARTS-reported
0 records
TMDL records

Each label shows where a statement comes from. How to read the labels.

Overview and location

Reported facility location HUC12 watershed Corroborated receiving water 2026 Integrated Report waterbodies nearby

Open this facility on the statewide map

Reported location Evidence: facility-reported

Coordinates
35.25633, -120.6733
Precision
4 decimal places
Shared point
No
Matches application record
same

Facility location as reported by the discharger in SMARTS; not a discharge point or outfall.

Facility address
35 Prado Rd, San Luis Obispo 93401
Regional Water Board
3 — Central Coast

HUC12 watershed Evidence: spatial

  • Lower San Luis Obispo Creek HUC12 180600060702

The facility's reported location lies within this HUC12 watershed (spatial derivation); it is not a discharge location.

Permits and applications Evidence: SMARTS record

Current permit record

Permit type
Industrial
Application type
Notice of Intent (WDID code I)
Status
Active
Operator
San Luis Obispo City
Primary industry (SIC)
4952-Sewerage Systems
Application ID
185686
NOI processed
Mar 13, 1992
Last certified
Jan 06, 2020
Facility size
52 Acres
Impervious area
100 %

Retrieved from SMARTS Oct 20, 2026. Verify against SMARTS before relying on it.

Permit history

Storm water applications for this WDID, newest first
ApplicationTypeStatusProcessedTerminatedCertified
185686 IndustrialActiveMar 13, 1992 —Jan 06, 2020

Every storm water application SMARTS records for this WDID, newest first (1).

Receiving water

Reported by the facility Evidence: facility-reported
San Luis Obispo Creek
Discharges directly / indirectly
Y / Y (as answered in the permit application)

Evidence: not confirmed Evidence: candidate, awaiting review Awaiting review

Receiving-water text as reported by the discharger in SMARTS; no waterbody identification has been confirmed.

Why it is not confirmed (1)
  • C1 name is only a prefix of official names

3 official waterbodies share this name; none is assigned without review.

Impaired waters and TMDLs

Two kinds of information, kept apart: 2026 Integrated Report waterbodies near the reported location (geographic proximity only), and TMDL records that SMARTS lists for this facility. Neither establishes where the facility discharges; see Receiving water for the facility's own statement.

Nearby waterbodies Evidence: geographic proximity

Spatial proximity only; discharge pathway not established. Being near a waterbody does not mean the facility discharges to it.

Nearest 2026 Integrated Report waterbodies
Waterbody (2026 Integrated Report)Distance2026 303(d) listAppendix A decisions
San Luis Obispo Creek (below Osos Street) CAR3102402119980828115513231 m listed7
Prefumo Creek CAR3102401220020124125422932 m listed5

Waterbodies within 1.0 km of the reported facility location. Method proximity/1.

SMARTS TMDL records Evidence: SMARTS-reported

No TMDL records for this facility in the SMARTS TMDL export.

Reported monitoring results Evidence: facility-reported

Numeric Action Level (NAL) screening is being independently validated and is not shown. Nothing on this page states whether a result exceeded a NAL.

214 distinct measurements across 4 parameters, most recent sample Feb 16, 2026.

By reporting year

Distinct results by reporting year
Reporting year (July–June)Distinct resultsParametersWith several versionsFirst sampleLast sample
2025213 0 Dec 24, 2025Feb 16, 2026
2021104 0 Oct 25, 2021Dec 13, 2021
2020324 0 Nov 18, 2020Mar 10, 2021
2019284 0 Nov 27, 2019Nov 18, 2020
2018324 0 Oct 04, 2018Jan 14, 2019
2017244 0 Dec 20, 2017Jan 08, 2018
2016364 0 Oct 28, 2016Feb 16, 2017
2015314 0 Nov 02, 2015Mar 11, 2016

By parameter

Distinct results by parameter
ParameterUnitsMeasurementsBelow detectionFirst sampleLast sampleResults
Oil and Greasemg/L58 33Nov 02, 2015Feb 16, 2026 Results
pHSU58 0Nov 02, 2015Feb 16, 2026 Results
Total Suspended Solids (TSS)mg/L58 1Nov 02, 2015Feb 16, 2026 Results
Electrical Conductivity @ 25 Deg. Cumhos/cm40 0Nov 02, 2015Oct 25, 2021 Results

All results (214 distinct rows)

Reported monitoring results, newest first
Sample dateParameterResultUnitsLocation typeEventMethodReportVersions
Feb 16, 2026 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1367600
Feb 16, 2026 pH 7.27 SU Effluent Qualifying Storm Event A4500HB 1367600
Feb 16, 2026 Total Suspended Solids (TSS) 55 mg/L Effluent Qualifying Storm Event A2540D 1367600
Jan 03, 2026 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1364272
Jan 03, 2026 pH 7.54 SU Effluent Qualifying Storm Event A4500HB 1364272
Jan 03, 2026 Total Suspended Solids (TSS) 28 mg/L Effluent Qualifying Storm Event A2540D 1364272
Dec 31, 2025 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1364130
Dec 31, 2025 Oil and Grease 1.81 mg/L Effluent Qualifying Storm Event E1664A 1364130
Dec 31, 2025 pH 8.49 SU Effluent Qualifying Storm Event A4500HB 1364130
Dec 31, 2025 pH 7.72 SU Effluent Qualifying Storm Event A4500HB 1364130
Dec 31, 2025 Total Suspended Solids (TSS) 12 mg/L Effluent Qualifying Storm Event A2540D 1364130
Dec 31, 2025 Total Suspended Solids (TSS) 74 mg/L Effluent Qualifying Storm Event A2540D 1364130
Dec 24, 2025 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1363509
Dec 24, 2025 Oil and Grease 2.45 mg/L Effluent Qualifying Storm Event E1664A 1363509
Dec 24, 2025 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1363509
Dec 24, 2025 pH 7.69 SU Effluent Qualifying Storm Event A4500HB 1363509
Dec 24, 2025 pH 7.75 SU Effluent Qualifying Storm Event A4500HB 1363509
Dec 24, 2025 pH 8.48 SU Effluent Qualifying Storm Event A4500HB 1363509
Dec 24, 2025 Total Suspended Solids (TSS) 61 mg/L Effluent Qualifying Storm Event A2540D 1363509
Dec 24, 2025 Total Suspended Solids (TSS) 247 mg/L Effluent Qualifying Storm Event A2540D 1363509
Dec 24, 2025 Total Suspended Solids (TSS) 13 mg/L Effluent Qualifying Storm Event A2540D 1363509
Dec 13, 2021 Oil and Grease 9.04 mg/L Effluent Qualifying Storm Event E1664A 1169521
Dec 13, 2021 Oil and Grease 9.04 mg/L Effluent Qualifying Storm Event E1664A 1173101
Dec 13, 2021 pH 7.88 SU Effluent Qualifying Storm Event A4500HB 1169521
Dec 13, 2021 pH 7.88 SU Effluent Qualifying Storm Event A4500HB 1173101
Dec 13, 2021 Total Suspended Solids (TSS) 650 mg/L Effluent Qualifying Storm Event A2540D 1169521
Dec 13, 2021 Total Suspended Solids (TSS) 650 mg/L Effluent Qualifying Storm Event A2540D 1173101
Oct 25, 2021 Electrical Conductivity @ 25 Deg. C 123.8 umhos/cm Effluent Qualifying Storm Event A2510B 1169521
Oct 25, 2021 Oil and Grease DNQ 2.1 mg/L Effluent Qualifying Storm Event E1664A 1169521
Oct 25, 2021 pH 8.03 SU Effluent Qualifying Storm Event A4500HB 1169521
Oct 25, 2021 Total Suspended Solids (TSS) 614 mg/L Effluent Qualifying Storm Event A2540D 1169521
Mar 10, 2021 Electrical Conductivity @ 25 Deg. C 147 umhos/cm Effluent Qualifying Storm Event 1149347
Mar 10, 2021 Electrical Conductivity @ 25 Deg. C 74.6 umhos/cm Effluent Qualifying Storm Event A2510B 1149347
Mar 10, 2021 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1149347
Mar 10, 2021 Oil and Grease 3.21 mg/L Effluent Qualifying Storm Event E1664A 1149347
Mar 10, 2021 pH 7.59 SU Effluent Qualifying Storm Event A4500HB 1149347
Mar 10, 2021 pH 7.77 SU Effluent Qualifying Storm Event A4500HB 1149347
Mar 10, 2021 Total Suspended Solids (TSS) 312 mg/L Effluent Qualifying Storm Event A2540D 1149347
Mar 10, 2021 Total Suspended Solids (TSS) 320 mg/L Effluent Qualifying Storm Event A2540D 1149347
Jan 27, 2021 Electrical Conductivity @ 25 Deg. C 355 umhos/cm Effluent Qualifying Storm Event A2510B 1144080
Jan 27, 2021 Electrical Conductivity @ 25 Deg. C 112 umhos/cm Effluent Qualifying Storm Event A2510B 1144080
Jan 27, 2021 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1144080
Jan 27, 2021 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1144080
Jan 27, 2021 pH 6.99 SU Effluent Qualifying Storm Event A4500HB 1144080
Jan 27, 2021 pH 6.65 SU Effluent Qualifying Storm Event A4500HB 1144080
Jan 27, 2021 Total Suspended Solids (TSS) 284 mg/L Effluent Qualifying Storm Event A2540D 1144080
Jan 27, 2021 Total Suspended Solids (TSS) 108 mg/L Effluent Qualifying Storm Event A2540D 1144080
Dec 28, 2020 Electrical Conductivity @ 25 Deg. C 298 umhos/cm Effluent Qualifying Storm Event A2510B 1139567
Dec 28, 2020 Electrical Conductivity @ 25 Deg. C 173 umhos/cm Effluent Qualifying Storm Event A2510B 1139567
Dec 28, 2020 Oil and Grease ND mg/L Effluent Qualifying Storm Event E1664A 1139567

Results are shown exactly as reported by the discharger. Identical rows repeated in the State's export are shown once. Where the export contains different versions of the same sample and parameter, each version is listed and flagged. Details.

Compliance and enforcement records Evidence: SMARTS record

These are records as the State Water Board publishes them in SMARTS, with the source's own types and statuses. They are not a compliance determination or rating. A record listed here is not proof of a violation beyond what the source states, and the absence of records does not establish compliance.

Compliance and enforcement records by type
Record typeRecordsAs publishedDatesRetrievedList
Violations2 2 Violation · 0 Potential (preliminary) · 0 Dismissed Jul 02, 1999 – Feb 07, 2005 Oct 21, 2026 All violations
Enforcement actions0 0 issued · 0 draft · 0 withdrawn, rescinded or superseded — Oct 21, 2026
Inspections0inspections, not findings — Oct 21, 2026
Annual reports11certified reports (contents not shown) 2015 – 2025 Oct 21, 2026 All reports
Water-quality-based corrective action reports0reports, by parameter — Oct 21, 2026

Each record type is counted by its own SMARTS identifier. A violation and the enforcement action that cites it are two records in two lists; they are never added together.

Chronological record history (13 records, newest first)
Compliance and enforcement records, newest first
DateRecordIDType or purposeStatus as publishedDetail
Jun 18, 2026 Annual reports 1335906 Annual report 2025 —
Jul 01, 2025 Annual reports 1294743 Annual report 2024 —
Jun 03, 2024 Annual reports 1243854 Annual report 2023 —
Aug 10, 2023 Annual reports 1113305 Annual report 2021 —
Jul 18, 2023 Annual reports 1189884 Annual report 2022 —
Jul 01, 2021 Annual reports 1069344 Annual report 2020 —
Jul 07, 2020 Annual reports 986654 Annual report 2019 —
Jul 01, 2019 Annual reports 954235 Annual report 2018 —
Jun 12, 2018 Annual reports 939652 Annual report 2017 —
Jul 03, 2017 Annual reports 878934 Annual report 2016 —
Jun 21, 2016 Annual reports 839865 Annual report 2015 —
Feb 07, 2005 Violations 263228 Unauthorized NSWD ViolationReport
Jul 02, 1999 Violations 143463 Deficient Report ViolationInspection

Sources and provenance

Sources behind this page
InformationSourceRetrieved or published
Permit, location, receiving-water textSMARTS Industrial Application Specific DataOct 20, 2026
Permit historySMARTS Storm Water ApplicationsOct 20, 2026
Monitoring resultsSMARTS Industrial Parameter DataOct 20, 2026
Watershed Boundary Dataset HU2 GeoPackages 15, 16, 18 (WBDHU12)USGS2026-10-22
2026 California Integrated Report, Appendix A: 2026 303(d) List (final)SWRCB2026-10-22
Final_2026_Rivers_and_Streams + Final_2026_Lakes_and_Reservoirs (FeatureServer 0)SWRCB GIS2026-10-22
SMARTS TMDL requirementsSMARTS2026-10-21

Relationships computed 2026-10-22 with methods facility_huc12/1, proximity/1, receiving_water/2, tmdl_reference/1, waterbody_huc12_ovl/1, waterbody_huc12_pub/1; proximity threshold 1.0 km.

How to read the evidence labels

Records are shown as published and are not compliance determinations. How geographic context is derived.