The following article provides insights for facility managers and others managing an industrial stormwater program who may need to leverage the victory of Gwaltney Foods factory to defend themselves in a time when citizen suits are at an all-time high. The 1987 decision issued in Gwaltney of Smithfield, Ltd. v. Chesapeake Bay Foundation set the scene for a tactic used by facilities defending themselves against the tar pit that is inevitable litigation. The case involved discharges into the Pagan River by Gwaltney Foods, a meat-packing company from Virginia. The initial award of $1.3 million ordered by the judge was the largest penalty ever imposed in a citizen enforcement case under the FWPCA (Clean Water Act) before the case was appealed to the U.S. Supreme Court. In its opinion, the Supreme Court explained that Congress intended citizen suits to play an “interstitial”, rather than “intrusive” role and were appropriate only where federal and state authorities have declined to exercise their enforcement power. Essentially, the Supreme Court ruled that plaintiffs in Clean Water Act §505 citizen suits must make a good faith allegation of ongoing or intermittent violation and citizen suits will be barred if another agency is already pursuing a civil claim. This holding had the effect of curtailing the ability for environmental coalitions to sue polluters for past violations. At the time, the defense felt it was a “90%” victory because the decision meant that the precedent set by the Court would give industrialists a measure of practical protection against citizen suits for violations that have ended before the suits are filed. Under Gwaltney, a defendant seeking a dismissal on mootness grounds faces a heavier burden where it must be “absolutely clear that the wrongful behavior would not reasonably be expected to recur”. In the thirty years since Gwaltney, the court’s ruling has joined a line of defenses against citizen suits that include challenging the plaintiff’s standing to maintain the suit, whether the plaintiff has met all the statutory requirements for notice, and most frequently, whether violations are actually “on-going”. In fact, as a result of Gwaltney the Clean Air Act was amended in 1990 to allow citizen suits for wholly past permit violations. The premise behind the case law that emerged from Gwaltney is that a business owner or facility manager can avoid being sued if they cure alleged conduct during the 60-day intent to sue period and take remedial measures to prevent future violations.