Pacific Gas Electric Company Diablo Canyon Power Plant

Active WDID 3 40I018248 Avila Beach, 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: Avila Beach, San Luis Obispo County; Region 3 · Central Coast · Location · Statewide map
Receiving water: Pacific Ocean (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: 1 waterbody; 1 on the 2026 303(d) list; Proximity only; not a discharge pathway · Nearby waterbodies
Monitoring results Evidence: facility-reported: 4,228 distinct results, 11 reporting years (2015 to 2025); Most recent sample Apr 21, 2026 · Monitoring
Compliance and enforcement records Evidence: SMARTS record: 2 inspections · 1 violation record · 3 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: 35.212222, -120.853889
Precision: 6 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: 9 Mi NW Of Avila Beach, Avila Beach 93424
Regional Water Board: 3 — Central Coast

HUC12 watershed Evidence: spatial

Islay Creek-Frontal Pacific Ocean HUC12 180600060504

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: Pacific Gas Electric Company Diablo Canyon Power Plant
Primary industry (SIC): 4911-Electric Services
Application ID: 185776
NOI processed: Jul 08, 2003
Last certified: Dec 19, 2024
Facility size: 585 Acres
Impervious area: 25 %

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

Permit history

Storm water applications for this WDID, newest first
Application	Type	Status	Processed	Terminated	Certified
185776	Industrial	Active	Jul 08, 2003	—	Dec 19, 2024

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

Receiving water

Reported by the facility Evidence: facility-reported: Pacific Ocean
Discharges directly / indirectly: N / N (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

290 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)	Distance	2026 303(d) list	Appendix A decisions
Pacific Ocean, Pt. Buchon to Pt. San Luis CAO3102500020200702053689	285 m	listed	1

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.

4,228 distinct measurements across 46 parameters, most recent sample Apr 21, 2026.

By reporting year

Distinct results by reporting year
Reporting year (July–June)	Distinct results	Parameters	First sample	Last sample
2025	399	35	Nov 13, 2025	Apr 21, 2026
2024	445	35	Nov 25, 2024	Mar 30, 2025
2023	483	35	Dec 18, 2023	Mar 29, 2024
2022	444	35	Nov 08, 2022	Mar 28, 2023
2021	355	35	Dec 13, 2021	Apr 21, 2022
2020	310	35	Dec 27, 2020	Mar 09, 2021
2019	399	36	Dec 22, 2019	Apr 05, 2020
2018	353	35	Nov 28, 2018	Jan 09, 2019
2017	353	35	Jan 08, 2018	Mar 20, 2018
2016	409	44	Nov 26, 2016	Mar 21, 2017
2015	278	26	Dec 13, 2015	Mar 11, 2016

By parameter

Distinct results by parameter
Parameter	Units	Measurements	Below detection	First sample	Last sample	Results
pH	SU	401	0	Dec 13, 2015	Apr 21, 2026	Results
Iron, Total	mg/L	400	96	Dec 13, 2015	Apr 21, 2026	Results
Total Suspended Solids (TSS)	mg/L	400	4	Dec 13, 2015	Apr 21, 2026	Results
Oil and Grease	mg/L	398	186	Dec 13, 2015	Apr 21, 2026	Results
Temperature	Degrees C	375	0	Dec 13, 2015	Apr 21, 2026	Results
Lead, Total	mg/L	146	59	Dec 13, 2015	Apr 21, 2026	Results
Nickel, Total	mg/L	146	22	Dec 13, 2015	Apr 21, 2026	Results
Chromium (Total)	mg/L	142	56	Dec 13, 2015	Apr 21, 2026	Results
Biochemical Oxygen Demand (BOD) (5-day @ 20 Deg. C)	mg/L	72	22	Dec 13, 2015	Feb 10, 2026	Results
Turbidity	NTU	72	0	Dec 13, 2015	Feb 10, 2026	Results
Arsenic, Total	mg/L	69	57	Dec 13, 2015	Feb 10, 2026	Results
Cadmium, Total	mg/L	69	63	Dec 13, 2015	Feb 10, 2026	Results

Show 34 more parameters

More parameters
Parameter	Units	Measurements	Below detection	First sample	Last sample	Results
Copper, Total	mg/L	69	0	Dec 13, 2015	Feb 10, 2026	Results
Mercury, Total	ug/L	69	68	Dec 13, 2015	Feb 10, 2026	Results
Selenium, Total	mg/L	69	55	Dec 13, 2015	Feb 10, 2026	Results
Silver, Total	mg/L	69	67	Dec 13, 2015	Feb 10, 2026	Results
Total Organic Carbon (TOC)	mg/L	69	0	Dec 13, 2015	Feb 10, 2026	Results
Zinc, Total	mg/L	69	0	Dec 13, 2015	Feb 10, 2026	Results
Acenaphthene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Acenaphthylene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Anthracene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Benzo(a)anthracene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Benzo(a)pyrene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Benzo(b)fluoranthene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Benzo(ghi)perylene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Benzo(k)fluoranthene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Chrysene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Dibenzo(a,h)anthracene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Fluoranthene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Fluorene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Indeno (1,2,3-cd) Pyrene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Naphthalene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Phenanthrene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Pyrene	ug/L	63	63	Nov 26, 2016	Feb 10, 2026	Results
Antimony, Total	mg/L	12	12	Dec 13, 2015	Jan 18, 2017	Results
Barium, Total	mg/L	12	0	Dec 13, 2015	Jan 18, 2017	Results
Beryllium, Total	ug/L	12	12	Dec 13, 2015	Jan 18, 2017	Results
Cobalt, Total	mg/L	12	11	Dec 13, 2015	Jan 18, 2017	Results
Molybdenum, Total	mg/L	12	11	Dec 13, 2015	Jan 18, 2017	Results
Thallium, Total	mg/L	12	10	Dec 13, 2015	Jan 18, 2017	Results
Vanadium, Total	mg/L	12	2	Dec 13, 2015	Jan 18, 2017	Results
Chronic Toxicity	TUc	10	0	Dec 15, 2016	Feb 10, 2026	Results
1-Methylnaphthalene	ug/L	6	6	Nov 26, 2016	Jan 18, 2017	Results
2-Methylnaphthalene	ug/L	6	6	Nov 26, 2016	Jan 18, 2017	Results
Polynuclear Aromatic Hydrocarbons (PAHs)	ug/L	6	6	Dec 13, 2015	Mar 11, 2016	Results
Chromium, Total Recoverable	mg/L	4	0	Dec 22, 2019	Dec 25, 2019	Results

All results (4,228 distinct rows)

Reported monitoring results, newest first
Sample date	Parameter	Result	Units	Location type	Event	Method	Report
Apr 21, 2026	Chromium (Total)	DNQ .00189	mg/L	Effluent	Qualifying Storm Event	E200.8	1372480
Apr 21, 2026	Chromium (Total)	DNQ .000878	mg/L	Effluent	Qualifying Storm Event	E200.8	1372480
Apr 21, 2026	Iron, Total	.57	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	.544	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	DNQ .385	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	ND	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	1.25	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	DNQ .371	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	ND	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Iron, Total	ND	mg/L	Effluent	Qualifying Storm Event	E200.7	1372480
Apr 21, 2026	Lead, Total	.071	mg/L	Effluent	Qualifying Storm Event	E200.8	1372480
Apr 21, 2026	Lead, Total	DNQ .000389	mg/L	Effluent	Qualifying Storm Event	E200.8	1372480
Apr 21, 2026	Nickel, Total	.00208	mg/L	Effluent	Qualifying Storm Event	E200.8	1372480
Apr 21, 2026	Nickel, Total	.00217	mg/L	Effluent	Qualifying Storm Event	E200.8	1372480
Apr 21, 2026	Oil and Grease	2.36	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	1.64	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	2.08	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	2.12	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	1.6	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	2.57	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	1.98	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	Oil and Grease	1.53	mg/L	Effluent	Qualifying Storm Event	E1664A	1372480
Apr 21, 2026	pH	7.1	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.55	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.41	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.52	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.28	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.49	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.63	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	pH	7.41	SU	Effluent	Qualifying Storm Event	pH_Field	1372480
Apr 21, 2026	Temperature	16	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	15.8	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	15.6	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	15.3	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	15.9	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	16.3	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	15.8	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Temperature	16.8	Degrees C	Effluent	Qualifying Storm Event	A2550B	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	11.6	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	22.5	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	15.1	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	10.2	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	77.6	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	8.9	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	7.9	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Apr 21, 2026	Total Suspended Solids (TSS)	3.8	mg/L	Effluent	Qualifying Storm Event	A2540D	1372480
Feb 16, 2026	Chromium (Total)	.00307	mg/L	Effluent	Qualifying Storm Event	E200.8	1368176
Feb 16, 2026	Chromium (Total)	DNQ .00154	mg/L	Effluent	Qualifying Storm Event	E200.8	1368176
Feb 16, 2026	Iron, Total	.945	mg/L	Effluent	Qualifying Storm Event	E200.7	1368176
Feb 16, 2026	Iron, Total	.765	mg/L	Effluent	Qualifying Storm Event	E200.7	1368176

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 type	Records	As published	Dates	Retrieved	List
Violations	1	1 Violation · 0 Potential (preliminary) · 0 Dismissed	Jul 01, 2004 – Jul 01, 2004	Oct 21, 2026	All violations
Enforcement actions	3	2 issued · 0 draft · 1 withdrawn, rescinded or superseded	Sep 10, 2004 – Sep 06, 2006	Oct 21, 2026	All actions
Inspections	2	inspections, not findings	Jun 24, 2011 – Feb 11, 2025	Oct 21, 2026	All inspections
Annual reports	11	certified reports (contents not shown)	2015 – 2025	Oct 21, 2026	All reports
Water-quality-based corrective action reports	0	reports, 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 (17 records, newest first)

Compliance and enforcement records, newest first
Date	Record	ID	Type or purpose	Status as published	Detail
Jul 10, 2026	Annual reports	1337194	Annual report 2025	—
Jul 10, 2025	Annual reports	1296095	Annual report 2024	—
Feb 11, 2025	Inspections	2067148	B Type compliance	Finalized	No Further Action
Jul 02, 2024	Annual reports	1245283	Annual report 2023	—
Jul 11, 2023	Annual reports	1191385	Annual report 2022	—
Jul 15, 2022	Annual reports	1114939	Annual report 2021	—
Jul 13, 2021	Annual reports	1063027	Annual report 2020	—
Jul 15, 2020	Annual reports	979889	Annual report 2019	—
Jul 11, 2019	Annual reports	956137	Annual report 2018	—
Jul 15, 2018	Annual reports	941562	Annual report 2017	—
Jul 13, 2017	Annual reports	880954	Annual report 2016	—
Jul 13, 2016	Annual reports	842584	Annual report 2015	—
Jun 24, 2011	Inspections	2012160	B Type compliance	—	No Further Action
Sep 06, 2006	Enforcement actions	321057	NOV (Notice of Violation)	Historical
Aug 01, 2006	Enforcement actions	320838	NOV (Notice of Violation)	Historical
Sep 10, 2004	Enforcement actions	254096	NOV (Notice of Violation)	Withdrawn	UNKNOWN
Jul 01, 2004	Violations	263377	Deficient Report	Violation	Inspection

Sources and provenance

Sources behind this page
Information	Source	Retrieved or published
Permit, location, receiving-water text	SMARTS Industrial Application Specific Data	Oct 20, 2026
Permit history	SMARTS Storm Water Applications	Oct 20, 2026
Monitoring results	SMARTS Industrial Parameter Data	Oct 20, 2026
Watershed Boundary Dataset HU2 GeoPackages 15, 16, 18 (WBDHU12)	USGS	2026-10-22
2026 California Integrated Report, Appendix A: 2026 303(d) List (final)	SWRCB	2026-10-22
Final_2026_Rivers_and_Streams + Final_2026_Lakes_and_Reservoirs (FeatureServer 0)	SWRCB GIS	2026-10-22
SMARTS TMDL requirements	SMARTS	2026-10-21

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

Evidence: SMARTS record Evidence: facility-reported Information as published in SMARTS or reported by the discharger.
Evidence: identification corroborated The reported receiving-water name identifies one official waterbody and the facility's location is consistent with it. It does not establish a discharge pathway.
Evidence: candidate, awaiting review Evidence: not confirmed The reported name could match one or more official waterbodies, but no identification has been confirmed; nothing is assigned without review.
Evidence: spatial Evidence: geographic proximity Derived from the reported location only.
Evidence: SMARTS-reported Source records whose links to official references are not yet reviewed.
Evidence: unavailable The information could not be loaded or is not in the sources.

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