On this page
In this lesson
What you'll learn
- Choose and apply the correct inspection schedule under the EPA CGP
- Know when inspection frequency increases or may be reduced
- Inspect every area and control the permit requires
- Complete and sign an inspection report within 24 hours
Who inspects
Inspections may be done by your own staff or a third party, but the inspector must be a qualified person. For EPA CGP coverage on or after February 17, 2023, that means completing EPA's construction inspection course for the permit and passing its exam, or holding a current, valid construction inspection certification or license from a program that covers the required topics. State permits set their own qualifications, such as California's QSP. See federal qualified person vs. California QSP/QSD.
How often: the standard schedules
Under CGP Part 4.2, choose one schedule and document it in the SWPPP:
- At least once every 7 calendar days, or
- Once every 14 calendar days and within 24 hours of either:
- A storm producing 0.25 inches or more of rain within 24 hours (multiple small storms that total 0.25 inches in 24 hours count), or
- A snowmelt discharge from a storm producing 3.25 inches or more of snow in 24 hours.
If you use the 14-day schedule, keep a rain gauge on site or use a representative weather station, and record the rainfall for any day with 0.25 inches or more. Inspections are only required during the site's normal working hours; if the 24-hour window falls entirely outside working hours, inspect by the end of the next business day.
When frequency increases
For any portion of the site that discharges to a sediment- or nutrient-impaired water, or to a Tier 2, 2.5 or 3 water (high-quality waters for antidegradation), inspect once every 7 calendar days and within 24 hours of a 0.25-inch storm or a qualifying snowmelt discharge (Part 4.3.1). Dewatering discharges are inspected once per day of discharge (Part 4.3.2).
When frequency may be reduced
- Stabilized areas: where the stabilization steps are complete, inspect twice in the first month (no more than 14 days apart), then once a month until coverage is terminated. Linear projects have their own variation.
- Arid, semi-arid and drought-stricken areas during the seasonally dry period or drought: once per month and within 24 hours of a 0.25-inch storm.
- Frozen conditions: the permit allows suspended or reduced inspections when frozen conditions meet its criteria.
What to inspect
At a minimum (CGP Part 4.5), inspect:
- All disturbed areas not yet stabilized.
- All stormwater controls, including pollution prevention controls, and track-out onto paved areas.
- Material, waste, borrow and equipment storage and maintenance areas.
- All areas where stormwater flows, including drainage features.
- Dewatering areas and controls.
- All points of discharge.
- All locations where stabilization has been implemented.
What to check
During each inspection (Part 4.6), check whether controls are properly installed, operational and working; look for conditions that could lead to spills or leaks; identify where new or modified controls are needed; look for erosion and sediment deposits at discharge points, on stream banks, in drainage features and on nearby streets; and note any noncompliance. If a discharge is occurring, identify the discharge points and observe and document its quality: color, odor, solids, foam, oil sheen and other indicators.
The inspection report
Complete the report within 24 hours of finishing the inspection (Part 4.7). Include the date, the inspectors' names and titles, a summary of findings including maintenance and corrective action needs, the rain gauge or weather station reading that triggered a storm inspection, and any areas that were unsafe to inspect and why. The report must be signed by the operator's authorized signatory. Keep reports with the SWPPP for at least 3 years after coverage ends.
Use our printable SWPPP inspection checklist in the field.
Key takeaways
- Inspectors must be qualified persons as defined by the permit.
- EPA CGP: every 7 days, or every 14 days plus within 24 hours of 0.25 inches of rain (or 3.25 inches of snow melting).
- Sensitive waters: every 7 days plus after 0.25-inch storms. Dewatering: daily during discharge.
- Inspect disturbed areas, every control, storage areas, flow paths, dewatering, discharge points and stabilized areas.
- Report within 24 hours, signed, and keep it 3 years.
Knowledge check
Lesson 9 quiz: 8 questions
Choose one answer for each question, then select Check my answers. Score 80% or higher to pass. Your answers stay in your browser and are never saved.
Sources and official references
Last reviewed: October 25, 2026 · Free general education based on the Clean Water Act, EPA NPDES rules and the EPA Construction General Permit. Your governing permit (EPA, state, tribal or local) controls. This is not legal advice, not EPA-approved, and not a California QSP/QSD or other state credential, and it does not issue a certificate. Nothing you enter on this page is saved or sent.