What is a waters of the United States (WOTUS) determination?
A waters of the United States determination, WOTUS for short, is the Corps district's ruling on whether federal law reaches your site at all. It comes before every other question in this whole area. A wetland delineation maps where the water sits; a nationwide permit screening asks which authorisation covers the discharge; but neither one means anything until jurisdiction itself is settled, because Section 404 only regulates a discharge of dredged or fill material into a water of the United States. Get the jurisdiction call wrong and every downstream step, the permit pathway, the acreage threshold, the pre-construction notification, is built on sand.
The three categories that survive Sackett
Before the Supreme Court's 2023 ruling in Sackett v. EPA, a wetland could qualify as jurisdictional through a fairly loose hydrological connection to a downstream water. Sackett threw that test out. Federal jurisdiction under the Clean Water Act now runs to three categories only, and a feature that does not fit one of them is not a water of the United States no matter how wet it gets.
| Feature | Typically jurisdictional | What decides it |
|---|---|---|
| Traditional navigable water | Yes | Used, or usable, for interstate or foreign commerce; the original, least contested category. |
| Relatively permanent tributary | Usually | Standing or continuously flowing water, not a channel that only runs after rainfall. |
| Adjacent wetland, abutting | Usually | Physically touches a jurisdictional water; a continuous surface connection, not just nearby. |
| Wetland separated by a berm or road | Rarely | A physical barrier breaks the surface connection even if water moves under or through it. |
| Isolated wetland, no outlet | No | No surface connection to any relatively permanent water, regardless of how it formed. |
| Ephemeral stream, storm flow only | No | Fails the relatively permanent test on its own; can still feed a jurisdictional water it flows into. |
Treat that table as a starting orientation, not a substitute for a district ruling. Sites sit close to these lines more often than the tidy categories suggest, and only the district's own determination is appealable and reliable enough to build a permit strategy on.
What is excluded outright, whatever the site looks like
A handful of features are carved out of federal jurisdiction by rule, not by a case-by-case call. Groundwater is excluded, however connected it is to a surface water underneath. Prior converted cropland stays excluded as long as it remains in agricultural use. Waste treatment systems built to meet Clean Water Act requirements are excluded by design. Certain ditches, particularly those excavated entirely in uplands and draining only uplands, are excluded too, though the exact line for ditches has moved with almost every rule change since 2015 and is worth confirming against the current definition before you rely on it.
Preliminary JD or approved JD: which one to ask for
Once you think you know where a site sits against the categories above, you can request a jurisdictional determination from your Corps district using the district's regulatory programme request process, typically an RFJD form plus a site map and, where one exists, a wetland delineation report. A preliminary JD is faster and cheaper to get: it states that jurisdictional waters may be present without ruling on the exact boundary, and it lets a project move into permitting on that assumption. An approved JD costs more time because the district has to do the underlying analysis itself, but it is the district's definitive, appealable finding of exactly which features are jurisdictional and where their limits sit, the version a lender or a buyer will actually want to see. Districts do not publish a single national turnaround time for either request; ask your specific district's regulatory branch what its current queue looks like before you build a schedule around either one.
The 2025 proposal would move these lines again
On 20 November 2025, EPA and the Corps published a proposed rule, docket EPA-HQ-OW-2025-0322, that would write the categories above into the regulatory text for the first time since Sackett. Under the agencies' own factsheet, a water would count as relatively permanent if it stands or flows year round, or at least through the local wet season, and a wetland would count as having a continuous surface connection if it abuts, meaning physically touches, a water that itself meets that standard. The proposal also adds a standalone exclusion for groundwater and rewrites the exclusions for ditches, prior converted cropland and waste treatment systems, changes a detailed legal breakdown of the text walks through section by section. Public comment closed 5 January 2026 and the agencies are working through that record now; nothing in the proposal is binding until a final rule is signed; and reaction split along predictable lines. Environmental Defense Fund vice president Will McDow called the approach not based in science and difficult to implement in practice, while the agencies frame the same wet season standard as the plain-language test Sackett itself called for. Whichever side is right, a determination requested today under post-Sackett guidance is not guaranteed to read the same way once a final rule lands, so a preliminary JD older than a year is worth a second look before anyone relies on it.
Where jurisdiction fits against everything else PermitBird screens
Confirming a site is a water of the United States is normally the step before, not after, commissioning a wetland delineation, because the delineation's three-parameter field test only matters once jurisdiction itself is on the table. Once jurisdiction and the delineation are both settled, whether the discharge actually needs a permit at all is covered in the wetland permit guide, and which of the 57 nationwide permits could apply is what the determination toolscreens for once you have a state, district, activity and impact number to enter. A project that clears the federal jurisdiction and permit questions can still run into a district's regional conditionsor a state's Section 401 water quality certification posture, so a WOTUS call in your favour is the start of the analysis, never the end of it.