The U.S. Supreme Court is considering a pair of cases that could cut back on the ability of citizens to enforce the Clean Water Act. Although different, at their core, both afford the court opportunities either to preserve or weaken the power of citizens to hold polluters accountable for harming our nation’s waters.

The Clean Water Act, enacted four decades ago, aimed to make the nation’s waters drinkable, fishable, and swimmable. To make good on this promise, it prohibits discharges of pollution into U.S. waters without a permit and holds polluters to the limits imposed in such permits. Congress gave citizens the power to enforce the Clean Water Act, for Congress recognized that the government often lacks the financial resources and political will to enforce environmental laws against violators. In this way, the Act enlists people who use treasured waters or live near facilities that expose their communities to untenable pollution to stand in the shoes of the government to enforce the law against wrongdoers.

The first case that was argued this week—Decker v. Northwest Environmental Defense Center—concerns logging roads actively used to haul timber. These roads pulverize gravel and spew sediment and logging detritus into adjacent streams through pipes, ditches and channels.

A local environmental group brought a citizen suit to force Oregon and the timber companies logging state forest in northwestern Oregon to get a permit limiting the pollution from these roads. Pollution from such logging roads chokes salmon eggs and young salmon, kills their prey, and buries their essential habitat. Numerous salmon streams exceeded water quality standards due to this type of pollution. In the court of appeals, the citizens won the right to pursue the case.

None of the parties will dispute that these roads cause serious pollution. Instead, what is before the court is whether citizens can even bring this enforcement action and attempt to prove that the pollution requires a permit.

The reasons for keeping the citizens out of court vary: the Environmental Protection Agency asks the court to defer to its view that decades-old regulations exempt logging roads from the Clean Water Act; the timber industry believes the citizens group is 25–35 years too late to bring the case; and the state of Oregon argues that it should be left to address the pollution as the state regulator sees fit. Of course, in this case, Oregon is not only the regulator, but also the landowner whose activities are causing the pollution, and its past efforts have failed to curb pollution from logging roads in this region.

The second case the court is considering—Los Angeles County Flood Control District v. Natural Resources Defense Council—could affect the enforceability of stormwater permits. When rains flow over parking lots, streets and lots, the resulting stormwater transports polluted water laden with toxic metals, lawn fertilizer, dog poop and other bacteria into lakes and rivers.

The Los Angeles area has some of the most persistent stormwater pollution problems, with toxic plumes of contaminated river water persisting miles into the open ocean for days. A complicated permit governs thousands of sources of stormwater that flow through channels ultimately into the Los Angeles and San Gabriel Rivers and then into the Pacific Ocean.

The citizens’ group brought an enforcement action when the designated monitoring stations revealed violations of the permit’s limits. LA County is arguing that since pollution levels aren’t measured where the stormwater enters the rivers, the pollution limits cannot be enforced. Some of the parties, however, would go further and block any enforcement action, no matter how strong the evidence, on the theory that moving the polluted water through the stormwater system is outside the law’s reach.

These cases fit a troubling pattern in which polluters and governments have been trying to close the courthouse door to citizen enforcement of our environmental laws. Too often, courts have acceded to those demands. With the federal government embroiled in budget-cutting negotiations to avoid sequestration, citizen enforcement is critically important. Such enforcement actions—people caring about particular rivers and stepping in at their own expense to make polluters follow the law—also serve to level the playing field so that some polluters don’t obtain a competitive advantage from polluting U.S. waters in violation of the laws other law-abiding players follow.

We need more, not less, citizen enforcement if strong laws on the books are to be the reality we see on the ground (or in the river).