Industrial Stormwater Lawsuits
Violations of the industrial stormwater general permits (IGP or ISGP) or multi-sector general permits (MSGP) can carry stiff financial penalties. In California, industrial stormwater discharges that violate the IGP carry up to a $37,500 per day penalty. Under the Clean Water Act (CWA), environmental groups can file citizen lawsuits against companies for violations of their stormwater permit.

Rain Logs Matter
This is where your rain log comes into incredibly handy. If you have a list of all the storm events, precipitation amounts, and whether you sampled or not, you can push back on these allegations of 1) discharge and 2) not sampling. Most facilities are not even keeping a rain log.
- Rain logging does not occur;
- Rain logs are stored on paper at another location; and
- Paper logs are not kept for five years (permit requirement).
What Should Be In a Rain Log
Rain logs should have a few components that address the aforementioned allegations in lawsuits and enable environmental and EHS managers to ensure samples are being collected. A good rain log should track the following:- Rain start and end date/time
- Stormwater samples collected (yes/no)
- Notes on whether discharge occurred
- Amount of rain
How Automatic Rain Logs Work
Mapistry’s stormwater compliance platform takes this all a huge step forward. Because we know facility staff are really, really busy and rain logs do not get done. We automated the logging of storm events.