Construction stormwater general permits do not impose one inspection frequency. They offer elections, and the operator picks one in the permit paperwork. Which one you elected decides every due date on your site, so it is worth knowing exactly which line you are on.
The table below is generated from the same rule matrix RainClock's clock engine runs, so it describes what the product actually enforces rather than a summary of it.
| Election | Routine interval | Storm trigger | Rule |
|---|---|---|---|
| EPA CGP: every 7 days (all weather) | every 7 calendar days | none (all weather) | EPA 2022 CGP Part 4.2.1 (every 7 calendar days) |
| EPA CGP: every 14 days + within 24h of a 0.25″ storm | every 14 calendar days | 0.25″ · 24h from occurrence | EPA 2022 CGP Part 4.2.1 (every 14 calendar days) |
| TXR150000: every 7 days (all weather) | every 7 calendar days | none (all weather) | TXR150000 Part III.F.8(c)(v) (every 7 calendar days) |
| TXR150000: every 14 days + within 24h of the end of a 0.5″ storm | every 14 calendar days | 0.5″ · 24h from storm end | TXR150000 Part III.F.8(c)(i) (every 14 calendar days) |
| Arid/semi-arid: monthly + post-storm | every 1 month | 0.25″ · 24h from storm end | Governing CGP arid/semi-arid provision (monthly inspections) |
Why the 24-hour window differs
The EPA CGP requires the post-storm inspection within 24 hours of the occurrence of a qualifying storm. TXR150000 measures the same 24 hours from the end of the storm event. On a long storm those are different deadlines, which is why RainClock records the event window rather than just a date.
Sources, both primary: EPA 2022 Construction General Permit (PDF) Part 4.2; TCEQ TXR150000 (2023) (PDF) Part III.F.8(c).
What RainClock does with this
You tell us your election when you add a site. We watch NOAA MRMS rainfall at the site coordinates, start the clocks your election implies, and name the rule on every one of them. We do not decide your election for you and we do not perform your inspections. The free rain log shows the calendar for any address.