NACWA filed an amicus brief last week supporting a group of Maryland municipalities challenging a state-issued National Pollutant Discharge Elimination System (NPDES) general permit for small MS4 operators that includes requirements beyond the maximum extent practicable (MEP) standard and requires MS4s to address nonpoint source runoff and other third-party stormwater discharges that neither flow into nor discharge from their systems. 

NACWA’s brief outlines the legal and technical reasons that MS4 operators can only be lawfully required to manage discharges from their systems, not third-party discharges and nonpoint source runoff over which they have no authority or control.  NACWA also explains how such requirements would inappropriately divert limited public resources to attempt to address private pollution.

NACWA’s brief likewise argues that states cannot lawfully impose requirements on MS4s that are beyond the statutory MEP standard, which many of the provisions in Maryland’s general permit attempt to do.  NACWA points out that such requirements would impermissibly expand the regulatory obligations on already overburdened clean water utilities and the communities they serve.

The MS4 coalition in the case, Maryland Small MS4 Coalition et. al. v. Maryland Department of the Environment, is being represented by NACWA Legal Affiliate AquaLaw.

While the Maryland Court of Appeals previously narrowly ruled against NACWA’s stormwater permitting positions in a 2019 decision involving an individual MS4 permit challenge in the case of MDE v. Carroll County, NACWA is hopeful that the court’s renewed interest in the issues in the present case may indicate a shift in judicial opinion that could allow for relief for Maryland MS4 operators and provide good legal precedent that other states could follow.

Please contact Amanda Aspatore, NACWA’s Chief Legal Counsel, with any questions.