City and County of San Francisco v. EPA
The Supreme Court ruled that the EPA cannot hold wastewater facilities responsible for overall water quality outcomes unless a permit actually spells out what the facility must do to achieve them — so-called 'end-result' permit conditions are not authorized by the Clean Water Act.
The decision limits a widespread EPA permitting practice used for cities with aging combined sewer systems and requires the agency to do the work of identifying and writing in specific obligations, rather than placing open-ended responsibility on the permit holder.
How it got here: San Francisco challenged two new permit conditions before the EPA's Environmental Appeals Board, lost, then petitioned the Ninth Circuit, which upheld the conditions; the Supreme Court agreed to hear the case.
The Case in Depth
What happened
San Francisco operates two treatment facilities that handle both sewage and stormwater through the same pipes. During heavy rain, these systems can overflow and discharge untreated sewage into the Pacific Ocean or San Francisco Bay. In 2019, the EPA added two new conditions to San Francisco's discharge permit stating the city could not contribute to violations of water quality standards or create pollution — without specifying what steps the city would need to take to prevent such violations.
The question before the Court
Can the EPA write water pollution permits that hold a city responsible for the overall quality of the water it discharges into, without specifying what concrete steps the city must actually take to achieve that quality?
The Court's answer
No — the Clean Water Act does not allow the EPA to write permit conditions that simply hold a city responsible for the quality of the water in the waterway it discharges into, without telling the city what specific steps it must take. The Court found that the word "limitation" in the relevant statute means a restriction imposed from outside that specifies what a permittee must or must not do — not an open-ended directive to achieve a certain outcome and figure out independently how to get there. The terms "implement" and "meet" in the statute reinforce this: they call for concrete prescribed measures, not a command to produce a result by whatever means the permittee chooses.
The Court also found that end-result requirements would undermine the Clean Water Act's "permit shield," which protects permittees from liability when they follow all their permit's specific terms. If a permittee could face fines of up to $25,000 per day — or even criminal prosecution — even after complying with every explicit permit condition, simply because water quality fell short, that protection would be meaningless. The statute's history reinforced the point: Congress deliberately replaced the old system of holding polluters accountable for overall water conditions with direct, specific restrictions on conduct, and the EPA's approach would revive exactly what Congress rejected.
Curious how the Court got there? See the step-by-step legal reasoning →
Why it matters
Cities and businesses with federal water discharge permits can no longer face enormous daily fines simply because a waterway fell below quality standards if the permit never told them what specific steps to take. The EPA must now identify and write in those concrete steps itself, a potentially complex undertaking that could slow permit renewals for municipalities and businesses across the country.
What changes now
The case is sent back to lower courts. The EPA must now write specific, concrete conditions for San Francisco's Oceanside facility permit rather than relying on end-result requirements. Going forward, the agency will need to identify and spell out what permittees must actually do to protect water quality. The decision may require the EPA to review and revise similar end-result conditions in other cities' and businesses' permits across the country, a potentially complex and time-consuming process.
What this does not decide
The ruling does not bar the EPA from requiring permit holders to follow specific "best practices," testing protocols, monitoring requirements, or other concrete operational obligations — including ones framed in narrative rather than numerical terms. The decision addresses only open-ended outcome-based conditions that leave the permittee to figure out independently how to achieve the required water quality.
Concurrences and dissents
Concurrence in part — Justice Gorsuch
Justice Gorsuch agreed with the core holding in Part III that §1311(b)(1)(C) does not authorize end-result requirements, and joined the judgment reversing the Ninth Circuit. He did not join Part II of the majority opinion, which rejected San Francisco's separate argument that all limitations under §1311 must qualify as effluent limitations. Justice Gorsuch did not write separately to explain his reasons for not joining that portion.
Dissent in part — Justice Barrett
Justice Barrett agreed with Part II of the majority, which rightly rejected San Francisco's argument that every limitation under §1311 must be an effluent limitation. But she would have upheld the EPA's authority to impose end-result requirements, arguing that a permit condition forbidding a city from contributing to water quality violations is plainly a 'limitation' as that word is ordinarily understood — limitations routinely state end results without prescribing the specific means of achieving them, just as a doctor may tell a patient to lose 20 pounds without prescribing a specific diet. She also rejected the majority's argument that end-result conditions revive the pre-1972 abatement regime, noting that these conditions operate as prospective permit requirements enforceable through the Act's existing civil penalty scheme — exactly the 'direct restrictions on polluters' the 1972 law intended.
How the Court got there
The legal reasoning, step by step
- The Court analyzed the text of §1311(b)(1)(C) of the Clean Water Act, which requires permits to include 'any more stringent limitation' necessary to 'implement' or 'meet' applicable water quality standards. It started with the word 'limitation,' defined as a restriction 'imposed from without' — meaning a rule the permit itself specifies. A directive that merely tells a permittee to achieve a good outcome and figure out how to get there imposes no restriction from outside; the restriction comes from the permittee's own self-devised compliance plan.
- The terms 'implement' and 'meet' in the statute pointed the same direction. 'Implement' standards means carrying them out 'by concrete measures' — devising and prescribing specific actions to ensure fulfillment. A limitation 'necessary to meet' a standard most naturally means one that sets out what a permittee must do to achieve the standard, not merely a directive to ensure the result occurs. The Court likened a school principal telling teachers to 'implement' math proficiency standards: the expectation is a concrete plan, not telling students to just pass the test.
- The Court drew on the history of federal water pollution law. Before 1972, the old Water Pollution Control Act held polluters liable by working backward from polluted water to identify who caused it — an enforcement model Congress found unworkable. The 1972 Clean Water Act deliberately replaced that backward-looking approach with direct, specific restrictions on polluters. End-result requirements, which hold a permittee liable whenever receiving water quality falls short regardless of what it did, replicate the same backward-looking logic Congress rejected.
- The Clean Water Act's 'permit shield' — which protects permittees from liability as long as they comply with all explicit permit conditions — would be gutted by end-result requirements. A permittee could follow every concrete step in its permit, yet still face fines up to $25,000 per day if water quality fell short for reasons outside its control. Potential penalties in the pending suit against San Francisco's other facility already reach $10 billion, illustrating how the shield's protection would be rendered hollow.
- The absence of any mechanism for dividing responsibility when multiple entities discharge into the same waterway reinforced the conclusion. If end-result requirements were valid, many dischargers could simultaneously be held responsible for the same water quality failure — yet Congress provided no way to allocate that shared liability fairly. The Court found it implausible that Congress silently preserved backward-looking liability while providing no framework for this obvious complication.
- The EPA argued it needs end-result requirements when it lacks enough information to write specific conditions. The Court rejected this: the agency has ample tools to gather needed information, including the power to set information-submission schedules and to withhold permits until applicants comply. The responsibility to determine what steps a permittee should take rests on the EPA, and Congress gave it the resources to discharge that responsibility.