Montana DEQ Permits Storm Water Runoff

April 16, 2019

In Montana, permits that govern large municipalities’ storm water runoff are allowed

The Montana Supreme Court upheld the Montana Department of Environmental Quality's establishment of new storm water discharge permits for six of the state's largest cities April 9, according to the Billings Gazette.

“The plaintiffs sought an overly prescriptive approach that would have resulted in excessive and costly monitoring at the expense of infrastructure improvements and other initiatives with a more direct impact on water quality,” said Tim Davis, DEQ's Water Quality Division administrator, to Billings Gazette.

In an abbreviation-filled ruling, five members of the court found the state agency was not arbitrary  nor did it act illegally, affirming Gallatin District Court Judge Rienne McElyea’s previous finding, according to the Billings Gazette.

According to the Billings Gazette, the ruling came from a court challenge by an Upper Missouri Waterkeeper. The group explained in its 2016 lawsuit that the new permit was insufficient because the public was not allowed to participate in setting new standards. The city of Billings was on the side of DEQ, according to the Billings Gazette.

"Montana citizens and local businesses dependent on our outdoors economy want to know the state and local jurisdictions are reducing stormwater pollution," said Guy Alsentzer, executive director for Upper Missouri Waterkeeper, to the Billings Gazette. "The court has denied these tougher municipal stormwater permits, and that’s disappointing."

According to the Gazette, Congress amended the Clean Water Act to address storm water runoff in 1987. The new permit was directed toward Municipal Separate Storm Sewer Systems (MS4s).

EPA defined MS4s as “not always just a system of underground pipes." According to the Gazette, the system can include roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains.

The law only targeted larger cities at the beginning, according to the Gazette. It was not until 1999 that the EPA shifted to also include smaller communities. Small MS4s serve populations of less than 100,000, and to comply, the Montana Board of Environmental Review adopted rules for small MS4s in 2003.