Industrial Stormwater Permitting requirements have been in place for over 20 years. Facilities that fall under one of eleven industry categories identified by the US Environmental Protection Agency (USEPA) and have material handling and storage, equipment maintenance and cleaning, and other activities exposed to stormwater are required to have a permit to discharge their stormwater runoff. Stormwater runoff is generated from rain and snowmelt events that flow over land or impervious surfaces, such as paved streets, parking lots, and building rooftops, and does not soak into the ground. The runoff picks up pollutants like trash, chemicals, oils, and dirt/sediment that can harm our rivers, streams, lakes, and coastal waters. Most often, industrial facilities are covered under General Permits issued by the State, but some facilities have individual permits.

Traditionally, facilities covered by General Permits have had a relatively low level of compliance oversite from regulators. State or local inspectors would show up in response to complaints or visit facilities that were high-profile and/or discharged into critical water bodies. However, the average manufacturing facility had a very low chance of seeing a stormwater inspector. Over the past several years, this has started to change.
The first increase started with local municipalities. Approximately ten years ago, the permits for Municipal Separate Storm Sewer Systems (MS4s) began requiring the MS4 operators to conduct inspections of the industrial sites that have stormwater discharges into the MS4. Those permits typically require the MS4 operator to conduct inspections of 20% of the industrial facilities each year. This means that each site should see an inspector at least once every five years. However, the majority of facilities do not discharge to MS4s; so most people have not dealt with these inspections.
Over the past year or two, there has been a push for greater oversite from the state agencies. There are two drivers for this: 1) the USEPA has asked states to significantly increase their inspection rate; and 2) there has been a shift in focus from construction stormwater to industrial stormwater. One source at a state agency reported that the USEPA has asked them to conduct 1,000 inspections per year, a major increase from their prior rate of less than 100. The other issue is that for almost two decades, there has been a significant push to control the discharges from construction sites, and most of the state resources for inspection were directed towards that goal. There have been significant strides in construction stormwater management over the past decades, and now the spotlight is shifting from construction to industrial activities, with a hope of similar results in increased runoff management.
In addition to the increased frequency of inspections, there is more data available to regulators. In 2015, the USEPA passed a rule requiring electronic reporting of most information related to water discharges. There was a phased implementation of the rule, but most states are now requiring electronic submission of all reports and Notices of Intent (NOIs), or they have plans to implement this in the next year. With the electronic submission of data, it is easier for regulators to identify facilities with recurring issues. For example, in some states, facilities that exceed stormwater benchmark values are being identified by regulators and asked to explain what corrective actions are planned, and are required to notify the state if the identified corrective actions are going to take longer than 90 days to abate or implement, in some instances. Gone are the days of simply filing your sampling and inspection results in your Storm Water Pollution Prevention Plan (SWP3) binder and expecting them to never be seen. Regulators are now taking a look.