← Facilities

Industrial stormwater facility

Mercer Fraser Trinidad

WDID 1 12I019994 · Notice of Intent · Trinidad, Humboldt

SIC 1429 · Crushed and Broken Stone, NEC · Regional Board 1 - North Coast Region

Official record — State Water Resources Control Board, Industrial General Permit

Hydrologic

Geographic context

Official facility coordinate plotted against the associated Final 2026 Integrated Report impaired-water geometry.

Loading map…
  • Facility location (official coordinate)
  • Associated impaired-water geometry (Final 2026 Integrated Report)
  • YDOS-derived geographic context
  • Loading associated geometry…

Geometry shown is limited to waterbodies geographically associated with this facility. Geographic association does not establish a discharge connection, receiving-water connectivity, or causation.

Official facility point
41.06495, -124.13235
HUC12 subwatershed
Luffenholtz Creek-Frontal Pacific Ocean
HUC12 code
180101020503
Impaired-water associations (derived)
6

Official

Facility record

Facility name
Mercer Fraser Trinidad
WDID
1 12I019994
Application type
Notice of Intent
City
Trinidad
County
Humboldt
ZIP
95570
Primary SIC code
1429
SIC description
Crushed and Broken Stone, NEC
Date active
2005-12-23
Regional Water Board
Regional Board 1 - North Coast Region

303(d) context

Associated impaired waters

Grouped by derived geographic association class.

Derived

Subwatershed + nearby

1 waterbodies
Trinidad HU, Big Lagoon HA, McConnahas Mill Creek

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (2) pH, Turbidity

Distance 0.72 km

Confidence high

Fact sheet

Same impaired-water subwatershed

5 waterbodies
Luffenholtz Beach

Coastal & Bay Shoreline · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (1) Indicator Bacteria

Distance

Confidence low

Fact sheet

Mad River HU, Norton Creek

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (1) Indicator Bacteria

Distance

Confidence low

Fact sheet

Moonstone County Park

Coastal & Bay Shoreline · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (1) Indicator Bacteria

Distance

Confidence low

Fact sheet

Trinidad HU, Big Lagoon HA, Freshwater Lagoon

Wetland, Freshwater · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (1) Mercury

Distance

Confidence low

Fact sheet

Trinidad State Beach

Coastal & Bay Shoreline · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (1) Indicator Bacteria

Distance

Confidence low

Fact sheet

Associations are calculated from official facility coordinates, USGS HUC12 boundaries, and official 2026 impaired-water geometry. They do not establish a discharge connection or causation.

TMDL requirements

Water Board-stated TMDL waste load allocations applied to this industrial permit in SMARTS.

Official record — SMARTS TMDL dataset, State Water Board

No SMARTS TMDL requirement is recorded for this WDID. In the statewide TMDL export only permits in Regions 4, 8 and 9 currently carry industrial TMDL requirements, so an absence here is not a statement that the facility discharges to an unimpaired water.

Official monitoring

SMARTS monitoring

Self-reported industrial stormwater sampling results as submitted by the discharger to SMARTS.

Official record — SMARTS parameter data, State Water Board
Reported results
108
Sample events
27
Distinct parameters
4
Reporting years
2015 – 2025
First sample
2015-11-24
Latest sample
2026-04-01
Source regional dataset
Region 1 - North Coast
Source retrieved
Aug 21, 2026

Official SMARTS public reports

Parameters reported

Reported results over time

Loading reported results…

Most recent reported results

Latest 25 of 108
Sample dateLocationParameterResultUnitsEvent
2026-04-01SP-2Nitrate/Nitrite (Nitrite + Nitrate as N).12mg/LQualifying Storm Event
2026-04-01SP-2Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01SP-2pH6.6SUQualifying Storm Event
2026-04-01SP-2Total Suspended Solids (TSS)44mg/LQualifying Storm Event
2026-03-05SP-2Nitrate/Nitrite (Nitrite + Nitrate as N).19mg/LQualifying Storm Event
2026-03-05SP-2Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2026-03-05SP-2pH7.2SUQualifying Storm Event
2026-03-05SP-2Total Suspended Solids (TSS)21mg/LQualifying Storm Event
2025-12-26SP-1Nitrate/Nitrite (Nitrite + Nitrate as N).46mg/LQualifying Storm Event
2025-12-26SP-1Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2025-12-26SP-1pH8.4SUQualifying Storm Event
2025-12-26SP-1Total Suspended Solids (TSS)27mg/LQualifying Storm Event
2025-12-26SP-2Nitrate/Nitrite (Nitrite + Nitrate as N).62mg/LQualifying Storm Event
2025-12-26SP-2Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2025-12-26SP-2pH8.4SUQualifying Storm Event
2025-12-26SP-2Total Suspended Solids (TSS)73mg/LQualifying Storm Event
2025-12-15SP-2Nitrate/Nitrite (Nitrite + Nitrate as N).481mg/LQualifying Storm Event
2025-12-15SP-2Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2025-12-15SP-2pH6.7SUQualifying Storm Event
2025-12-15SP-2Total Suspended Solids (TSS)25mg/LQualifying Storm Event
2025-03-12SP-2Nitrate/Nitrite (Nitrite + Nitrate as N)ND (non-detect / est.)mg/LQualifying Storm Event
2025-03-12SP-2Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2025-03-12SP-2pH7SUQualifying Storm Event
2025-03-12SP-2Total Suspended Solids (TSS)70mg/LQualifying Storm Event
2025-01-31SP-2Nitrate/Nitrite (Nitrite + Nitrate as N).18mg/LQualifying Storm Event

Monitoring rows are official self-reported SMARTS submissions, joined to this facility by WDID. California Stormwater Intelligence does not restate, correct, average or evaluate reported values, and no benchmark comparison or violation determination is made.

YDOS-derived

Numeric Action Level comparison

Reported SMARTS analytical results compared against the Numeric Action Levels of the Industrial General Permit version in effect for each reporting year (July 1 – June 30).

Derived
Reporting years evaluated
8
Years with an NAL exceedance
1
Most recent evaluated year
RY 2025
Ruleset
igp_nal_ruleset_v1 / igp_nal_v1
ParameterNAL typeCalculated valueNALResultSamples usedMethod

Nitrite Plus Nitrate (as N)

nitrate_nitrite_n

Annual0.374 mg/L as N0.68 mg/L as NAt or below NALAnnual average of 5 eligible result(s) compared with the annual NAL.0.55× threshold5 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Oil and Grease

oil_grease

Instantaneous maximum0 samples above25 mg/LAt or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL.5 eligible5 non-detect as zerocount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

pH

ph

Instantaneous maximum0 samples above6 – 9 pH unitsWithin NAL rangeNo eligible result in this reporting year was outside the instantaneous maximum NAL.5 eligiblecount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

Total Suspended Solids (TSS)

tss

Instantaneous maximum0 samples above400 mg/LAt or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL.5 eligiblecount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

An NAL exceedance is a permit-defined condition that triggers Exceedance Response Actions under the Industrial General Permit. It is not a violation, an enforcement action, or a Water Board compliance determination. Annual values use the arithmetic average of eligible results with non-detects treated as zero; instantaneous maximum NALs (total suspended solids, oil and grease, pH) are exceeded when two or more eligible results in a reporting year fall outside the level. Rules transcribed from 2014-0057-DWQ as amended by 2015-0122-DWQ (effective 2015-07-01, superseded 2020-06-30); 2014-0057-DWQ as amended by 2018-0028-DWQ (effective 2020-07-01).

Documents

Documents on file

Attachment inventory recorded in the State Water Board SMARTS public attachment workflow for this permit.

Source inventory — SMARTS public attachments. Documents are operator-submitted.

Metadata indicators

Derived
Substantive documents on file
88
SWPPP versions on file
3
Most recent SWPPP attached
2020-12-11
Most recent substantive document
2026-07-14
Annual report years on file
2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
Apparent year gaps in annual reports
None apparent
ERA-related documents
0
Enforcement / inspection / laboratory documents
0 / 2 / 28

Document indicators are YDOS-derived counts and dates calculated from SMARTS attachment metadata. They describe what is on file, not whether a facility complied with any requirement.

88 substantive of 124 indexed attachments

SWPPP

4 documents

Trinidad Amendment No. 2 Temporary Suspension

Source file type SWPPP · 2020-12-11 · 3.2 MB

Trinidad Amendment No. 2 Temporary Suspension

Source file type SWPPP · 2020-12-11 · 3.2 MB

Trinidad Quarry Site Map

Source file type Facility/Site Map · 2020-12-11 · 3.8 MB

Trinidad Amendment No. 2 Temporary Suspension

Source file type SWPPP · 2020-12-11 · 3.2 MB

Annual report

32 documents

Submitted report pdf

Source file type Submitted Report PDF · 2026-07-14 · 819 KB

Submitted report pdf

Source file type Submitted Report PDF · 2026-04-15 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2026-04-02 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2026-02-18 · 406 KB

Submitted report pdf

Source file type Submitted Report PDF · 2026-01-26 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-07-14 · 999 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-05-05 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-03-17 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-01-27 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-01-27 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-07-12 · 406 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-07-12 · 1000 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-07-14 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-07-14 · 1000 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-06-01 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2022-07-14 · 1000 KB

Submitted report pdf

Source file type Submitted Report PDF · 2021-07-15 · 1000 KB

Submitted report pdf

Source file type Submitted Report PDF · 2021-02-02 · 104 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-07-15 · 1000 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-05-26 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-04-23 · 104 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-01-16 · 104 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-12-23 · 104 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-07-12 · 1000 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-05-31 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-05-02 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-01-21 · 406 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-01-04 · 406 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-07-13 · 911 KB

Submitted report pdf

Source file type Submitted Report PDF · 2017-07-10 · 11 KB

Submitted report pdf

Source file type Submitted Report PDF · 2016-07-13 · 911 KB

Submitted report pdf

Source file type Submitted Report PDF · 2016-05-19 · 407 KB

Inspection

2 documents

050824 inspection memo

Source file type Final Inspection Report · 2024-05-16 · 2.2 MB

041323 inspection report

Source file type Final Inspection Report · 2023-05-10 · 2.5 MB

Laboratory / ad hoc

28 documents

Trinidad Sampling Lab Results 4-1-2026

Source file type Laboratory Results · 2026-04-15 · 736 KB

Trinidad Sampling Lab Results 3-5-2026

Source file type Laboratory Results · 2026-04-02 · 746 KB

Trinidad Lab Results 12-26-2025

Source file type Laboratory Results · 2026-02-18 · 325 KB

Trinidad Lab Results 12-15-2025

Source file type Laboratory Results · 2026-01-26 · 586 KB

Trinidad Sampling Lab Results 3-12-25

Source file type Laboratory Results · 2025-04-16 · 597 KB

Trinidad Sampling Lab Results 1-31-25

Source file type Laboratory Results · 2025-03-17 · 657 KB

Trinidad Sampling Visual Observation 12-16-2024

Source file type Laboratory Results · 2025-01-27 · 405 KB

Trinidad Sampling Visual Observation 12-12-2024

Source file type Laboratory Results · 2025-01-23 · 414 KB

Trinidad Sampling Lab Results 6-3-2024

Source file type Laboratory Results · 2024-07-10 · 321 KB

Trinidad Sampling 5-8-2023

Source file type Laboratory Results · 2023-07-13 · 324 KB

Trinidad Sampling 4-17-2023

Source file type Laboratory Results · 2023-05-29 · 359 KB

12-15-2020 Lab Results

Source file type Laboratory Results · 2021-01-27 · 284 KB

Lab Results 4-22-2020

Source file type Laboratory Results · 2020-05-26 · 267 KB

Laboratory Results 3-30-2020

Source file type Laboratory Results · 2020-04-23 · 223 KB

12-19-2019 Laboratory Results

Source file type Laboratory Results · 2020-01-16 · 223 KB

Lab Results 11-26-2019

Source file type Laboratory Results · 2019-12-23 · 226 KB

5-15-2019 Lab Results

Source file type Laboratory Results · 2019-05-31 · 314 KB

Lab Results 4/11/2019

Source file type Laboratory Results · 2019-05-02 · 307 KB

Lab Results

Source file type Laboratory Results · part 1/1 · 2019-01-04 · 346 KB

Lab Results

Source file type Laboratory Results · part 1/1 · 2019-01-04 · 387 KB

MFC Trinidad Stormwater 160226

Source file type Laboratory Results · part 1/1 · 2016-05-19 · 271 KB

MFC Trinidad Stormwater 160128

Source file type Laboratory Results · part 1/1 · 2016-05-19 · 199 KB

MFC Trinidad Stormwater 151217

Source file type Laboratory Results · part 1/1 · 2016-05-19 · 273 KB

MFC Trinidad Stormwater 151124

Source file type Laboratory Results · part 1/1 · 2016-05-19 · 198 KB

MFC Trinidad Storm Water 160226

Source file type Laboratory Results · part 1/1 · 2016-03-11 · 271 KB

MFC Trinidad 160128

Source file type Laboratory Results · part 1/1 · 2016-02-12 · 199 KB

MFC Trinidad Storm Water 151217

Source file type Laboratory Results · part 1/1 · 2016-01-19 · 273 KB

Trinidad Storm Water 151124

Source file type Laboratory Results · part 1/1 · 2015-12-10 · 504 KB

Other substantive

22 documents

SWPPP Amendment No. 6

Source file type Other · 2025-04-21 · 2.5 MB

Trinidad Sampling Visual Observation 6-3-2024

Source file type Supporting Documentation · 2024-07-10 · 1.1 MB

Trinidad SWPPP Amendment No. 5

Source file type Other · 2024-05-13 · 298 KB

Trinidad SWPPP Amendment No. 4

Source file type Other · 2023-10-30 · 465 KB

Trinidad SWPPP Amendment No. 3_REV1

Source file type Other · 2023-04-13 · 314 KB

Trinidad SWPPP Amendment No. 3

Source file type Supporting Documentation · 2023-03-13 · 182 KB

Sampling Log

Source file type Supporting Documentation · part 1/1 · 2019-01-04 · 315 KB

Sampling Log

Source file type Supporting Documentation · part 1/1 · 2019-01-04 · 409 KB

Trinidad ISWPPP Amendment No.001

Source file type Other · part 1/1 · 2018-05-31 · 3.9 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-06-30 · 3.7 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-06-30 · 1.8 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-06-30 · 3.6 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-06-30 · 2.8 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-02-09 · 3.2 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-02-09 · 2.3 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-02-09 · 2.8 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2016-02-09 · 3.0 MB

141017_DCJ_ef_IGPExceedance_MercerFraserTrinidad.pdf

Source file type Cover/Explanation Letter · part 1/1 · 2014-10-28 · 335 KB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2014-02-25 · 1.9 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2014-02-25 · 2.3 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2014-02-25 · 2.4 MB

Mercer Fraser Trinidad

Source file type Photograph · part 1/1 · 2014-02-25 · 2.4 MB

Enforcement

Enforcement records

Enforcement actions as recorded by the State Water Board for this permit, in the source system's own terminology.

Source record — SMARTS enforcement data

Structured enforcement records are not yet connected for this site. The absence of a record is not a finding about this facility.

Reporting

Reporting and ERA records

Annual report and Exceedance Response Action information as stated by the source system, distinguished from what is inferred from document metadata.

Source record — SMARTS reporting data

Annual report documents on file

Derived
Reporting years identified
2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
Apparent year gaps
None apparent

Years are YDOS-derived from attachment metadata. A gap means no annual-report document was identified for that year in the attachment index — it is not a finding that a report was not filed.

Recent activity

Recent source changes

New or changed source records this platform detected for this permit, newest first.

Derived

No source change has been detected for this permit yet. Change detection begins from the date each dataset was first indexed.

Provenance

Source & provenance

Source agency
California State Water Resources Control Board
Source dataset
Industrial General Permit — permitted facilities (statewide GIS layer)
WDID
1 12I019994
Source feature ID
9182
Application type
Notice of Intent
Regional board derivation
WDID region prefix
Geometry status
valid
Last successful facility import
Sep 16, 2026, 10:48 PM UTC

Official IGP permitted facilities feature layer