On March 18, 2020, the Appellate Division affirmed the Department of Environmental Protection’s November 9, 2017 decision to renew the Tier A municipal separate storm sewer system (MS4) general permit. (Delaware Riverkeeper Network v. NJDEP, Dkt. A-1821-17T3.) Stormwater discharges must be permitted by DEP. General permits streamline the permitting process by avoiding the time and expense associated with issuing individual permits to each municipality. The general permit at issue in this case authorizes the discharge of stormwater from MS4s owned or operated by 457 urban or coastal municipalities throughout New Jersey.

The decision sets forth in detail the permitting history of MS4 discharges since 1987, and explains that the current permit has been strengthened from the prior iteration based on EPA comments. The decision also highlights the challenges associated with regulating stormwater. By way of example, the permit requires Tier A municipalities to adopt and enforce various community-wide ordinances, including pet waste ordinances, wildlife-feeding ordinances, and litter control ordinances, and to maintain a log of related enforcement actions in their stormwater pollution prevention plan so that the DEP can verify compliance. In affirming the permit decision, the Court also acknowledged the limited deference afforded to agencies interpreting regulations within their enforcement responsibilities, and emphasized the need for site specific, flexible standards.

Regarding the specific arguments raised on appeal, the permit challengers argued that the general permit was unlawful because it failed to include effluent monitoring that measures mass and volume of pollutants. Citing to federal regulations, the Appellate Division found no such monitoring was required and that the Best Management Practices (BMPs) and monitoring mandated by the general permit sufficed. The challengers also argued, among other things, that the permit failed to include effluent limits consistent with wasteload allocations previously adopted by DEP. The Appellate Division found that the “overarching federal law for MS4s … is broad and flexible. It does not require the DEP to implement numeric effluent limitations; BMPs are appropriate.” Finally, the decision also explained that DEP conducts a wide array of ambient water quality monitoring and that if water quality standards are not met, the DEP may review a municipality’s permit and make revisions.