A Definitive Guide for Facilities to Navigate the IGP and RWQCB Expectations in 2026
California’s stormwater scene is evolving and 2026 is shaping up to be a watershed year for industrial stormwater compliance. With the Industrial General Permit (IGP) still administratively continued and updated through State and Regional Water Boards, facilities must be proactive about numeric thresholds, monitoring, adaptive planning, and documentation. Here is what California industrial operators need to know now.
What Is the California Industrial General Permit (IGP)?
The IGP (State Water Board Order No. 2014-0057-DWQ) regulates stormwater discharges associated with industrial activities that drain to waters of the United States. Although originally adopted in 2014 and amended in 2015 and 2018, it continues in effect through administrative continuation until a new permit is formally adopted.
Under the IGP, industrial operations like manufacturing, recycling, transport maintenance yards, landfills, and other facilities listed in Attachment A must:
Enroll under the permit via the SMARTS system or secure a No-Exposure or Non-Applicability status if eligible Maintain a tailored Stormwater Pollution Prevention Plan (SWPPP) Conduct routine monitoring and implement BMPs Submit reports and respond to exceedances of numeric measures
In many regions, Regional Water Quality Control Boards (RWQCBs) are increasing scrutiny and inspections, especially in sensitive watersheds.
Numeric Action Levels (NALs)
California’s IGP uses Numeric Action Levels (NALs) as thresholds for common pollutants such as pH, TSS (total suspended solids), oil and grease, heavy metals, and other indicators. These thresholds serve as early warning triggers for corrective action.
Important points for 2026:
- An NAL exceedance is not an automatic violation but it requires corrective action under the exceedance response action (ERA) process.
- There are multiple trigger types including “instantaneous maximum” exceedances and “annual average” exceedances, both requiring response plans.
- Corrective actions can include BMP upgrades, enhanced controls, or additional treatment to address specific pollutants.
- Repeated NAL exceedances may escalate into Numeric Effluent Limitations (NELs) and potential penalties under mandatory minimum penalty provisions.
These numeric levels and responses ensure that industrial dischargers not only monitor but also act promptly to reduce pollution rather than just document it.
Monitoring Expectations for 2026
Under the current IGP structure in California:
Qualifying Storm Event (QSE) Sampling
Facilities must collect stormwater samples from each discharge point for multiple QSEs per reporting year.
Conventionally this has meant at least four QSE sampling events, two in the first half of the reporting year and two in the second.
Visual Observations
During each QSE and routine inspections, visual checks for sheen, discoloration, sediment, or other signs of pollution are required.
Laboratory Analysis
Samples are analyzed for standard indicators like pH, TSS, and oil and grease, plus any parameters relevant to your operations or specific impaired waterbodies.
SMARTS Reporting
Results must be uploaded into the State Water Board’s SMARTS database, with Ad-Hoc Reports submitted within 30 days of lab results.
Annual Report
A summary of compliance activities and monitoring data must be filed by July 15 each year.
RWQCB Roles and Regional Nuances
California is divided into nine Regional Water Quality Control Boards, each with enforcement authority over stormwater discharges in its area. While the statewide IGP sets the baseline rules, RWQCBs can:
- Prioritize inspections in sensitive watersheds
- Impose TMDL (Total Maximum Daily Load)-specific requirements
- Require additional monitoring or BMP measures if pollutant loads threaten receiving waters
Some regions are particularly stringent, especially where impaired waterbodies are present. This means your facility may have additional numeric pollutant responsibilities beyond baseline NALs.
Qualified Industrial Stormwater Practitioners (QISP)
In many compliance scenarios, especially after NAL exceedances, the IGP requires that corrective action plans, evaluations, and technical reports be prepared by a Qualified Industrial Stormwater Practitioner (QISP). QISPs help ensure that investigations and action plans meet regulatory expectations and technical rigor.
Training and certification help your team avoid common pitfalls, and many RWQCBs expect documentation prepared or stamped by QISPs for higher levels of compliance evaluation.
Common Mistakes That Get Facilities in Trouble
As regulations mature, enforcement action tends to focus on recurring issues:
- Incomplete or outdated SWPPPs. Generic plans without site-specific pollutant sources and BMPs fall short under inspection.
- Late or missing SMARTS uploads. Untimely reports draw attention from inspectors and may trigger enforcement.
- Ignoring response action requirements. Permittees must act when NAL triggers occur, even if it is not a violation yet.
- Lack of documentation. Inadequate logs for inspections, maintenance, or training undermine defense during an audit.
Penalties and Enforcement You Should Know
Non-compliance with the IGP has consequences:
- Not obtaining coverage. Enforcement and fines under California Water Code.
- Repeated NAL/NEL exceedances. Potential for enforcement escalation and mandatory minimum penalties.
- Failure to report or corrective act. Can trigger Notices of Violation (NOVs), Cease and Desist Orders (CDOs), or Administrative Civil Liability (ACL) actions.
Staying ahead of schedules, documentation, and corrective actions is far easier and cheaper than reacting to enforcement.
Your 2026 Compliance Action Plan
- Update Your SWPPP. Make it site-specific with clearly identified pollutant sources, BMPs, and adaptive actions.
- Review NAL Triggers. Not just meeting numeric levels but understanding what they mean and how they trigger action.
- Stay on SMARTS Deadlines. Upload visual observations, sampling data, and annual reports on time.
- Train and Certify. Ensure roles like QISPs and stormwater team members are properly trained.
- Document and Respond. Log everything from inspections to BMP maintenance and act promptly when thresholds are triggered.
Conclusion
California’s stormwater regulations demand more than compliance by default. By understanding how Numeric Action Levels, monitoring regimes, and regional expectations play out in 2026 and beyond, your facility can stay compliant, avoid penalties, and protect water quality effectively.