Is Your Facility Covered Under California's Industrial General Permit?

Coverage is based on your facility's Standard Industrial Classification (SIC) code and whether industrial materials or activities are exposed to stormwater. Most manufacturing, metal finishing, recycling, and warehousing operations with outdoor exposure fall under one of the permit's ten covered sectors. A site review is the fastest way to confirm your status.

A No Exposure Certification (NEC) is available only when industrial materials and activities are completely protected from rain and stormwater contact. It's a narrow exemption, not a default — most industrial sites with any outdoor storage, loading, or processing don't qualify and need full permit coverage instead.

A Qualified Industrial Stormwater Practitioner (QISP) is a state-certified professional required to develop and implement Exceedance Response Action evaluations once a facility triggers Level 1 or Level 2 ERA status — that certification isn't optional at that point, it's a permit requirement. Many facilities also bring in a QISP earlier, for routine sampling, visual observations, and initial SWPPP development, since the same expertise that gets you through an ERA also catches the gaps that would trigger one in the first place. Working with a QISP from the start typically means fewer surprises at Level 1, not just a faster response once you're already there.

There's no making it up after the fact. Sampling has to happen within the specific window tied to a qualifying storm event, and once that window closes, it's closed — you can't go back and collect a late sample to fill the gap. It gets logged in SMARTS as a missed event and can be cited as a permit violation on its own, whether or not any actual discharge or exceedance occurred that period.

There's no confirmed date yet. The State Water Board has been working on a revised Industrial General Permit for several years — an informal draft and public process were expected to move it toward adoption, but that timeline has slipped more than once, and as of now the current permit (Order 2014-0057-DWQ, amended in 2015 and 2018) remains in effect through administrative continuation. In practical terms, that means your facility complies with the existing IGP requirements until a new permit is formally adopted — waiting for the rewrite isn't a compliance strategy. Plaid Safety tracks the State Water Board's process and will flag what changes for your facility once a new permit is actually finalized.

It might, but not automatically. TMDL requirements only apply if you're a "Responsible Discharger" — meaning your facility discharges one of the specific pollutants that has a wasteload allocation under that waterbody's TMDL, not just any facility located nearby. New dischargers to a 303(d)-impaired waterbody are addressed specifically under Section VII.B of the IGP, separate from the general TMDL provisions. If you are a Responsible Discharger, Attachment E sets both TMDL-specific Numeric Action Levels (TNALs) and Numeric Effluent Limitations (NELs) for your facility — and a NEL exceedance is treated as an immediate violation, not a two-strikes ERA trigger like a standard NAL. Determining applicability requires matching your receiving waterbody, your discharged pollutants, and Attachment E — worth confirming before you file your NOI, not after.

Not on its own. A single exceedance of a Numeric Action Level is expected to happen occasionally. What matters is the response: two exceedances of the same parameter trigger a Level 1 ERA evaluation, and failing to complete that evaluation and report on time is what creates a violation.

Yes. Regional Water Board staff can conduct unannounced inspections, and citizen suits under the Clean Water Act are also a real enforcement channel for facilities with public SMARTS records showing gaps or exceedances.