Stormwater season in California is winding down, but for many permittees under the Industrial General Permit (IGP), that means ERA season is just getting started.
If your facility exceeded Numeric Action Levels (NALs) this monitoring year, you’re likely required to submit an Exceedance Response Action (ERA). Whether you're in Level 1 or Level 2, the deadlines are real, the requirements are detailed, and enforcement is active.
Here’s what California facilities need to know to stay compliant, and how expert support can keep you out of trouble.

What is an ERA?
Level 1: You must submit an ERA Evaluation prepared by a Qualified Industrial Stormwater Practitioner (QISP), identifying sources of pollution and suggesting Best Management Practices (BMPs).
Level 2: You’re required to submit a Technical Report with site-specific design or structural BMPs developed by a QISP — often involving engineered upgrades.
An ERA is a mandated response when stormwater sample results exceed specified pollutant benchmarks (NALs). Facilities that exceed these thresholds are required to evaluate and document what went wrong and what corrective actions they’ll take to fix it.
There are two ERA tiers:
How Do I Know If I Need to File?
Start by reviewing your QSE (Qualifying Storm Event) sample results. Did any exceed these common NALs?
Total Suspended Solids (TSS)
Oil & Grease (O&G)
pH
Facility-specific pollutant benchmarks (e.g., metals)
If so, you're likely in Level 1 or Level 2 status — depending on prior years' performance.
Still unsure? Let us complete a sampling review to check your exceedances and help determine your filing requirements.
What’s Required in the Report?
ERA Level | Required Actions |
---|---|
Level 1 | On-site evaluation, pollutant source tracking, review of current BMPs, and proposed improvements |
Level 2 | Site-specific BMP design, QISP-led reporting, submission of technical report including performance projections |
These reports must be completed and submitted through the SMARTS system by the official deadline.
What Happens If I Don’t File?
California regulators and environmental groups are actively monitoring non-compliant sites. Missing your ERA obligations could result in:
Formal enforcement actions
Fines and penalties
Lawsuits from environmental NGOs
Loss of permit coverage
In short, ERA noncompliance is a liability your business can't afford.
How We Help
At Frog Environmental, we specialize in stormwater compliance and ERA reporting. Our team includes certified QISPs and stormwater professionals who have filed hundreds of ERA Evaluations and Technical Reports for facilities across California.
We handle:
Data analysis + NAL comparison
On-site evaluations
BMP planning and design
SMARTS report submission
Regulatory communication
Not Sure Where to Start?
We’ve created a set of free downloadable resources to help you navigate ERA season with confidence:
ERA Information and Timelines (PDF)
Let’s Make This Season Less Stressful
We believe ERA season doesn't have to be a scramble. With the right support and a clear plan, you can stay compliant, avoid fines, and protect your facility from unwanted attention.
Request a free compliance assessment to get started.