In the next decade, the Multi-Sector General Permit (MSGP) for industrial stormwater is expected to be required of more facilities. This comes after a court order forces the EPA to modernize stormwater permits.
The MSGP covers rain or snowmelt that can be measured in a downstream river, stream, ditch, gutter or pipe shortly after precipitation has reached the ground and passes through some sort of engineered conveyance like a gutter, pipe or concrete canal. Measurements are regulated under the Clean Water Act.
The difficulty in managing the measurements of industrial stormwater is due in part because of the wide range of industrial sectors that must be accounted for, each of which produces a unique suite of contaminants in stormwater. The industrial stormwater permit program includes a small number of individual facility permits as well as general permits that are issued to groups of industries at the state and federal level.
In order to help regulate better, the EPA will be taking recommendations from the National Academies of Sciences, Engineering, and Medicines, who has conducted studies that help evaluate the needs for certain industrial sectors to be added to the permit, the cost implications and so forth.
Roughly 4,000 facilities currently comply with the current MSGP. Any changes to the permit will influence state water regulators who use the permits to write benchmarks and best management practices (BMPs).