San Mateo Transit Dist So Base

Active WDID 2 41I003233 San Carlos, San Mateo County Region 2 · San Francisco Bay

At a glance

Permit Evidence: SMARTS record
Active Industrial
Notice of Intent (WDID code I) · Permits and applications
Location Evidence: facility-reported
San Carlos, San Mateo County
Region 2 · San Francisco Bay · Location · Statewide map
Receiving water
Redwood City Retention Basin (as reported by the facility)
Evidence: not confirmed 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
None
Monitoring results Evidence: facility-reported
716 distinct results, 11 reporting years (2015 to 2025)
Most recent sample Apr 20, 2026 · Monitoring
Compliance and enforcement records Evidence: SMARTS record
1 inspection · 3 violation records · 6 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
37.51633, -122.25312
Precision
5 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
501 Pico Blvd, San Carlos 94070
Regional Water Board
2 — San Francisco Bay

HUC12 watershed Evidence: spatial

  • San Francisco Bay Estuaries-Frontal San Francisco Bay HUC12 180500041001

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 Mateo Transit District
Primary industry (SIC)
4173-Terminal and Service Facilities for Motor Vehicle Passenger Transportation
Application ID
182864
NOI processed
Apr 03, 1992
Last certified
Oct 07, 2026
Facility size
11 Acres

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

Permit history

Storm water applications for this WDID, newest first
ApplicationTypeStatusProcessedTerminatedCertified
182864 IndustrialActiveApr 03, 1992 —Oct 07, 2026

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

Receiving water

Reported by the facility Evidence: facility-reported
Redwood City Retention Basin
Discharges directly / indirectly
Y / N (as answered in the permit application)

Evidence: not confirmed Not matchable to a single waterbody

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

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.

No 2026 Integrated Report waterbody lies within the proximity threshold of the reported location.

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.

716 distinct measurements across 88 parameters, most recent sample Apr 20, 2026.

By reporting year

Distinct results by reporting year
Reporting year (July–June)Distinct resultsParametersWith several versionsFirst sampleLast sample
202563 0 Oct 13, 2025Apr 20, 2026
202463 0 Nov 11, 2024Jan 03, 2025
202393 0 Dec 27, 2023Mar 29, 2024
202216384 0 Mar 09, 2023Mar 28, 2023
20216969 0 Dec 13, 2021Dec 13, 2021
202020369 0 Jan 04, 2021Mar 18, 2021
201914070 0 Jan 16, 2020Mar 14, 2020
20183212 0 Nov 29, 2018May 18, 2019
20172413 0 Mar 01, 2018Mar 13, 2018
2016164 0 Feb 16, 2017Mar 24, 2017
20154812 0 Nov 02, 2015Apr 09, 2016

By parameter

Distinct results by parameter
ParameterUnitsMeasurementsBelow detectionFirst sampleLast sampleResults
pHSU28 0Nov 02, 2015Apr 20, 2026 Results
Total Suspended Solids (TSS)mg/L28 4Nov 02, 2015Apr 20, 2026 Results
Oil and Greasemg/L24 19Feb 16, 2017Apr 20, 2026 Results
Zinc, Totalmg/L19 0Nov 02, 2015Dec 13, 2021 Results
Cadmium, Totalmg/L15 12Nov 02, 2015Dec 13, 2021 Results
Chromium (Total)mg/L15 3Nov 02, 2015Dec 13, 2021 Results
Lead, Totalmg/L15 5Nov 02, 2015Dec 13, 2021 Results
Nickel, Totalmg/L15 3Nov 02, 2015Dec 13, 2021 Results
Orthophosphate, Total (as P)mg/L13 6Nov 02, 2015Mar 28, 2023 Results
1,1,1-Trichloroethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,1,2,2-Tetrachloroethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,1,2-Trichloroethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Show 84 more parameters
More parameters
ParameterUnitsMeasurementsBelow detectionFirst sampleLast sampleResults
1,1-Dichloroethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,1-Dichloropropeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2,3-Trichlorobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2,3-Trichloropropaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2,4-Trichlorobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2,4-Trimethylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2-Dibromo-3-Chloropropaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2-Dibromoethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2-Dichlorobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2-Dichloroethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,2-Dichloropropaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,3,5-Trimethylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,3-Dichlorobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,3-Dichloropropaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,4-Dichlorobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
2,2-Dichloropropaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
4-Chlorotolueneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Benzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Bromobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Bromochloromethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Bromoformug/L8 8Jan 16, 2020Mar 28, 2023 Results
Bromomethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Carbon Tetrachlorideug/L8 8Jan 16, 2020Mar 28, 2023 Results
Chlorobenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Chloroethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Chloroformug/L8 8Jan 16, 2020Mar 28, 2023 Results
Chloromethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Dibromomethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Dichlorodifluoromethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Ethylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Hexachlorobutadieneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Isopropylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
m,p-Xylenesug/L8 8Jan 16, 2020Mar 28, 2023 Results
Methyl Ethyl Ketoneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Methyl Tert-butyl Ether (MTBE)ug/L8 8Jan 16, 2020Mar 28, 2023 Results
Methylene Chlorideug/L8 8Jan 16, 2020Mar 28, 2023 Results
n-Butylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
n-Propylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Naphthaleneug/L8 8Jan 16, 2020Mar 28, 2023 Results
o-Xyleneug/L8 8Jan 16, 2020Mar 28, 2023 Results
p-Isopropyltolueneug/L8 8Jan 16, 2020Mar 28, 2023 Results
sec-Butylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Styreneug/L8 8Jan 16, 2020Mar 28, 2023 Results
tert-Butylbenzeneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Tetrachloroetheneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Tolueneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Trichloroetheneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Trichlorofluoromethaneug/L8 8Jan 16, 2020Mar 28, 2023 Results
Vinyl Chlorideug/L8 8Jan 16, 2020Mar 28, 2023 Results
Xylenes, Totalug/L8 8Jan 16, 2020Mar 28, 2023 Results
1,1,1,2-Tetrachloroethaneug/L7 7Jan 16, 2020Mar 09, 2023 Results
cis-1,2-Dichloroetheneug/L7 7Jan 16, 2020Mar 28, 2023 Results
cis-1,3-Dichloropropeneug/L7 7Jan 16, 2020Mar 28, 2023 Results
Diesel Oilmg/L7 0Nov 02, 2015Nov 29, 2018 Results
Halogenated Volatile Organic Compounds (HVOC)ug/L7 7Nov 02, 2015May 18, 2019 Results
TPH as Motor Oilmg/L7 0Nov 02, 2015Nov 29, 2018 Results
trans-1,2-Dichloroetheneug/L7 7Jan 16, 2020Mar 28, 2023 Results
trans-1,3-Dichloropropeneug/L7 7Jan 16, 2020Mar 28, 2023 Results
Trichlorotrifluoroethaneug/L7 7Jan 16, 2020Mar 09, 2023 Results
Dibromodichloromethaneug/L6 6Jan 16, 2020Dec 13, 2021 Results
Acetoneug/L4 2Jan 16, 2020Mar 28, 2023 Results
Electrical Conductivity @ 25 Deg. Cumhos/cm4 0Nov 02, 2015Apr 09, 2016 Results
Orthophosphate, Total (as P)ug/L4 4Jan 04, 2021Dec 13, 2021 Results
4-Methyl-2-pentanoneug/L3 0Mar 13, 2018Mar 28, 2023 Results
1,1-Dichloroethyleneug/L2 2Mar 09, 2023Mar 28, 2023 Results
2-Chlorotolueneug/L2 2Mar 09, 2023Mar 28, 2023 Results
2-Hexanoneug/L2 2Mar 09, 2023Mar 28, 2023 Results
Cadmium, Totalug/L2 2Mar 09, 2023Mar 28, 2023 Results
Carbon disulfideug/L2 2Mar 09, 2023Mar 28, 2023 Results
Chromium (Total)ug/L2 0Mar 09, 2023Mar 28, 2023 Results
Dibromochloromethaneug/L2 2Mar 09, 2023Mar 28, 2023 Results
Dichlorobromomethaneug/L2 2Mar 09, 2023Mar 28, 2023 Results
Ethyl-Tert Butyl Ether (ETBE)ug/L2 2Mar 09, 2023Mar 28, 2023 Results
Hexachloroethaneug/L2 2Mar 09, 2023Mar 28, 2023 Results
Isopropyl Etherug/L2 2Mar 09, 2023Mar 28, 2023 Results
Lead, Totalug/L2 0Mar 09, 2023Mar 28, 2023 Results
Nickel, Totalug/L2 0Mar 09, 2023Mar 28, 2023 Results
Tert-Amyl Methyl Ether (TAME)ug/L2 2Mar 09, 2023Mar 28, 2023 Results
Tert-Butyl Alcohol (TBA)ug/L2 2Mar 09, 2023Mar 28, 2023 Results
Zinc, Totalug/L2 0Mar 09, 2023Mar 28, 2023 Results
1,1,2-Trichloro-1,2,2-Trifluoroethaneug/L1 1Mar 28, 2023Mar 28, 2023 Results
2-propanone (Acetone)ug/L1 0Mar 13, 2018Mar 13, 2018 Results
Diesel Oilug/L1 0Mar 28, 2023Mar 28, 2023 Results
TPH as Motor Oilug/L1 1Mar 09, 2023Mar 09, 2023 Results

All results (716 distinct rows)

Reported monitoring results, newest first
Sample dateParameterResultUnitsLocation typeEventMethodReportVersions
Apr 20, 2026 Oil and Grease < 1.9 mg/L Effluent Qualifying Storm Event E1664A 1373069
Apr 20, 2026 pH 6.76 SU Effluent Qualifying Storm Event pH_Field 1373069
Apr 20, 2026 Total Suspended Solids (TSS) 70 mg/L Effluent Qualifying Storm Event A2540D 1373069
Oct 13, 2025 Oil and Grease 2 mg/L Effluent Qualifying Storm Event E1664A 1354929
Oct 13, 2025 pH 6.31 SU Effluent Qualifying Storm Event E150.2 1354929
Oct 13, 2025 Total Suspended Solids (TSS) 94 mg/L Effluent Qualifying Storm Event A2540D 1354929
Jan 03, 2025 Oil and Grease < 1.6 mg/L Effluent Qualifying Storm Event E1664A 1318927
Jan 03, 2025 pH 7.38 SU Effluent Qualifying Storm Event E150.2 1318927
Jan 03, 2025 Total Suspended Solids (TSS) 25 mg/L Effluent Qualifying Storm Event A2540D 1318927
Nov 11, 2024 Oil and Grease < 1.6 mg/L Effluent Qualifying Storm Event E1664A 1315353
Nov 11, 2024 pH 6.96 SU Effluent Qualifying Storm Event E150.2 1315353
Nov 11, 2024 Total Suspended Solids (TSS) 32.8 mg/L Effluent Qualifying Storm Event A2540D 1315353
Mar 29, 2024 Oil and Grease < 2.5 mg/L Effluent Qualifying Storm Event E1664A 1283389
Mar 29, 2024 pH 7.91 SU Effluent Qualifying Storm Event pH_Field 1283389
Mar 29, 2024 Total Suspended Solids (TSS) 13.6 mg/L Effluent Qualifying Storm Event A2540D 1283389
Jan 31, 2024 Oil and Grease < 2.5 mg/L Effluent Qualifying Storm Event E1664A 1276093
Jan 31, 2024 pH 8.9 SU Effluent Qualifying Storm Event pH_Field 1276093
Jan 31, 2024 Total Suspended Solids (TSS) 29 mg/L Effluent Qualifying Storm Event A2540D 1276093
Dec 27, 2023 Oil and Grease < 2.5 mg/L Effluent Qualifying Storm Event E1664A 1276086
Dec 27, 2023 pH 6.4 SU Effluent Qualifying Storm Event pH_Field 1276086
Dec 27, 2023 Total Suspended Solids (TSS) 182 mg/L Effluent Qualifying Storm Event A2540D 1276086
Mar 28, 2023 1,1,1-Trichloroethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,1,2,2-Tetrachloroethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,1,2-Trichloro-1,2,2-Trifluoroethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,1,2-Trichloroethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,1-Dichloroethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,1-Dichloroethylene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,1-Dichloropropene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2,3-Trichlorobenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2,3-Trichloropropane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2,4-Trichlorobenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2,4-Trimethylbenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2-Dibromo-3-Chloropropane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2-Dibromoethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2-Dichlorobenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2-Dichloroethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,2-Dichloropropane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,3,5-Trimethylbenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,3-Dichlorobenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,3-Dichloropropane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 1,4-Dichlorobenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 2,2-Dichloropropane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 2-Chlorotoluene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 2-Hexanone ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 4-Chlorotoluene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 4-Methyl-2-pentanone 3.6 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 Acetone DNQ 12 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 Benzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 Bromobenzene ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644
Mar 28, 2023 Bromochloromethane ND 0 ug/L Effluent Qualifying Storm Event SW8260B 1235644

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
Violations3 3 Violation · 0 Potential (preliminary) · 0 Dismissed Jul 02, 2007 – Jul 15, 2022 Oct 21, 2026 All violations
Enforcement actions6 6 issued · 0 draft · 0 withdrawn, rescinded or superseded Aug 06, 2007 – Jan 11, 2023 Oct 21, 2026 All actions
Inspections1inspections, not findings Sep 29, 2022 – Sep 29, 2022 Oct 21, 2026 All inspections
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 (21 records, newest first)
Compliance and enforcement records, newest first
DateRecordIDType or purposeStatus as publishedDetail
Jun 17, 2026 Annual reports 1335159 Annual report 2025 —
Jul 14, 2025 Annual reports 1293962 Annual report 2024 —
Jun 24, 2024 Annual reports 1243039 Annual report 2023 —
Sep 06, 2023 Annual reports 1189032 Annual report 2022 —
Feb 09, 2023 Annual reports 1112389 Annual report 2021 —
Jan 11, 2023 Enforcement actions 449313 2nd NNC - AR (Second Notice of Non-Compliance (annual report)) Active
Dec 07, 2022 Enforcement actions 449198 1st NNC - AR (First Notice of Non-Compliance (annual report)) Active
Sep 29, 2022 Inspections 2057850 B Type compliance PerformedAdditional Info Required
Jul 15, 2022 Violations 884253 Late Report ViolationReport
Jul 14, 2021 Annual reports 1068393 Annual report 2020 —
Jul 13, 2020 Annual reports 985629 Annual report 2019 —
Jun 28, 2019 Annual reports 953169 Annual report 2018 —
Dec 19, 2018 Annual reports 938585 Annual report 2017 —
Jul 06, 2017 Annual reports 877809 Annual report 2016 —
Jul 13, 2016 Annual reports 844666 Annual report 2015 —
Feb 11, 2009 Enforcement actions 368352 NOV (Notice of Violation) Historical
Oct 31, 2008 Enforcement actions 357991 NNC (Notice of Non-Compliance) Historical
Aug 22, 2008 Enforcement actions 357620 NNC (Notice of Non-Compliance) Historical
Jul 02, 2008 Violations 798999 Late Report ViolationReport
Aug 06, 2007 Enforcement actions 357297 NNC (Notice of Non-Compliance) Historical
Jul 02, 2007 Violations 798542 Late Report ViolationReport

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.