Los Angeles County Flood Control District v. Natural Resources Defense Council, Inc.
The Supreme Court ruled that water flowing from a concrete-lined section of a river into an unlined section of the same river is not a new "discharge of a pollutant" under the Clean Water Act, because nothing is being added to the water body — it is simply moving within it.
The decision reverses a Ninth Circuit ruling that would have made a flood-control agency liable for pollution levels detected where water exits concrete channels, reinforcing a narrower reading of when the Clean Water Act's permit-liability rules kick in.
How it got here: A federal trial court ruled for the flood-control district; the Ninth Circuit reversed in part; the district asked the Supreme Court to review that reversal.
The Case in Depth
What happened
Los Angeles County's Flood Control District operates a large storm-drain system that collects and discharges storm water, much of which is polluted, into the Los Angeles and San Gabriel Rivers under a federal pollution permit. Environmental groups Natural Resources Defense Council and Santa Monica Baykeeper sued, pointing to pollution readings at monitoring stations inside the rivers as proof the District was violating its permit, even though thousands of other entities also discharge into the same rivers upstream.
The question before the Court
If storm water in a concrete-lined stretch of a river flows downstream into an unlined stretch of the very same river, does that count as a new "discharge of a pollutant" under the Clean Water Act?
Why it matters
Local flood-control and storm-sewer agencies across the country won't be automatically liable under the Clean Water Act just because polluted water measured inside their own drainage channels later flows into unlined stretches of the same river. Environmental groups suing over storm-water pollution will need other evidence \u2014 such as permit-violation theories \u2014 to hold operators responsible for pollutants that originate from other upstream sources.
What changes now
The case goes back to the lower courts. The Ninth Circuit's ruling that the flood-control district was liable simply because pollution was detected where water left the concrete channels is undone. The environmental groups' separate argument \u2014 that the District's own permit terms make the monitoring-station readings enough to prove a permit violation \u2014 was never decided by the Court and remains open for the lower courts to consider on remand.
What this does not decide
The Court decided only the narrow question of whether flow within the same river counts as a new discharge; it did not decide whether the District's permit terms independently made the monitoring-station pollution readings enough to prove a violation. That separate argument, raised by the environmental groups, was left unresolved.
Concurrences and dissents
Concurrence — Justice Alito
Justice Alito agreed with the outcome — reversing the Ninth Circuit — but did not join the Court's opinion or its reasoning. The opinion does not include any separate writing explaining his specific grounds for concurring only in the judgment.
How the Court got there
The legal reasoning, step by step
- The Court applied its earlier ruling in Miccosukee Tribe, which held that moving polluted water between two parts of the same water body — without removing it and putting it somewhere new — does not count as "adding" a pollutant under the Clean Water Act.
- The Court read the Act's text, which defines a regulated discharge as an "addition" of a pollutant to navigable waters, and reasoned that transferring water from one stretch of a river to another stretch of the identical river adds nothing new to that water body.
- It illustrated the point with an analogy: ladling soup out of a pot and pouring it back in does not add soup to the pot, even though the soup moved.
- Applying that logic, the Court concluded that water flowing out of a concrete-lined section of the Los Angeles and San Gabriel Rivers into an unlined section of the same rivers is not a new discharge, because the concrete channel and the unlined channel are simply two parts of one river, not separate water bodies.
- Because the Ninth Circuit had found liability based on exactly that kind of within-river flow, its reasoning could not stand under the rule the Court had already set out in Miccosukee.
Doctrinal impact
Cases affected by this decision
Reaffirms South Fla. Water Management Dist. v. Miccosukee Tribe (541 U. S. 95)
The Court relies on and extends this ruling that moving polluted water within one water body isn't a regulated discharge.