How Long Is a Wetland Delineation Good For? 5-Year Rule

A wetland delineation, once the U.S. Army Corps of Engineers issues an Approved Jurisdictional Determination on it, is good for five years from the date of the letter.¹ That’s the standard federal window, and it applies to the Corps’ binding ruling on your property, not to the consultant’s underlying fieldwork. Site changes, new regulatory interpretations, and the type of determination you actually hold can all shorten or complicate that timeline.

The Five-Year Rule for Approved Determinations

An Approved Jurisdictional Determination (AJD) is the Corps’ legally enforceable ruling that federal waters or wetlands are present, or absent, on your property. Under Regulatory Guidance Letter 05-02, an AJD remains valid for five years from the date of the letter, unless new information or changing environmental conditions justify a revision.¹ The Corps set that window because wetlands shift over time: hydrology changes, vegetation communities evolve, and soil conditions fluctuate with weather and surrounding land use.

While the AJD is active, you can rely on it for permit decisions, property transactions, and development planning. You also have the right to appeal the boundaries through the Corps’ administrative appeals process, a right that doesn’t exist with a preliminary determination.²

One useful wrinkle: if the AJD was issued as part of an individual permit, the determination generally remains valid for the life of that permit, even after the standalone five-year window has passed. That keeps long-running projects from losing their jurisdictional basis midway through construction.

A Delineation Report Without Corps Approval Is Just an Opinion

The fieldwork itself, walking the property, testing soils, cataloging vegetation, evaluating hydrology, and drawing wetland boundaries on a map, is what most people mean when they say “delineation.”² But the delineation report a consultant produces has no legal validity period on its own. It becomes legally meaningful only when submitted to the Corps and confirmed through a jurisdictional determination. So when someone asks how long a delineation is “good for,” the answer really depends on what the Corps has issued on top of that report.

Preliminary Determinations Have No Expiration, but Cost You Elsewhere

A Preliminary Jurisdictional Determination (PJD) is not a binding ruling. It simply flags that there “may be” waters of the United States on the property and identifies features that could be affected by your proposed activity.¹

PJDs have no expiration date.² The catch is real, though. Because a PJD is non-binding, the Corps treats every aquatic feature on your parcel as jurisdictional for permitting purposes. Accepting a permit based on a PJD means agreeing that all aquatic resources in the review area will be treated as federally regulated, which typically drives up compensatory mitigation and adds restrictions you wouldn’t face under an AJD that identifies only the features actually under federal jurisdiction. The speed you gain by skipping a full AJD often gets erased by the mitigation bill on anything larger than a minimal-impact project.

What Can Shorten the Five-Year Window

Even a valid AJD can stop reflecting reality before its five years are up.

Physical Changes to the Site

Wetlands are defined by hydrology, vegetation, and soils. Anything that materially alters one of those factors can move the boundaries. Prolonged drought can shrink wetland areas. Upstream construction can redirect water flow and expand them. Extensive clearing removes the vegetation that partly defines a wetland. If the site looks substantially different from when the fieldwork was done, the paperwork no longer matches the ground.

The Sackett Decision

The Supreme Court’s ruling in Sackett v. EPA (2023) significantly narrowed which wetlands qualify for federal protection. The Court held that a wetland must have a “continuous surface connection” to a traditionally navigable water, making the wetland essentially indistinguishable from the water itself.³ The earlier “significant nexus” test, which extended jurisdiction to wetlands with a meaningful ecological connection to navigable waters even without a direct surface link, was rejected.

That matters for anyone holding a pre-2023 AJD. Wetlands classified as federally jurisdictional under the old standard may no longer qualify. EPA and the Army have proposed a rule to formally implement the decision, with the public comment period closing in January 2026.⁴ Some features previously excluded may also come back into play under state regulations that apply a broader definition than the new federal one.

Revalidating Before Expiration

If the AJD is nearing five years and the project isn’t finished, you can ask the Corps to revalidate. Revalidation is lighter than starting over, but it isn’t automatic. The Corps will want evidence that site conditions haven’t materially changed, which usually means recent site photographs and often a new field visit by a qualified wetland professional to confirm the boundaries.

Revalidation is more likely when the site hasn’t been physically altered, surrounding land use is stable, and no major regulatory changes have occurred since the original AJD. If any of those aren’t met, expect the Corps to require a full new delineation.

When You Have to Start Over

A fresh delineation is the only option in several situations:

Major site disturbance such as grading, filling, rerouting drainage, or clearing vegetation, which changes the very features the original delineation was built on.
An expanded project footprint that reaches into areas the original delineation didn’t cover.
Upgrading from a PJD to a binding AJD for permitting or a real estate transaction; the Corps cannot convert one to the other without a full evaluation.
An expired AJD where you can’t demonstrate site stability, which sends you back to new fieldwork and a fresh Corps review.

Cost and Timing

Professional delineation fees generally start around $3,500 for a straightforward small site. Larger or more complex properties cost substantially more, since fieldwork time, the number of soil test pits, vegetation sampling points, and report length all scale with acreage and complexity. That fee is separate from Corps processing and from any compensatory mitigation owed if the project impacts jurisdictional wetlands.

Because the five-year clock starts when the AJD is issued, timing the delineation too early in planning can force you to pay for revalidation or a second delineation before you break ground. Most consultants recommend starting the process about a year before permits are needed, which allows enough runway for fieldwork, report preparation, and Corps review while leaving most of the five-year window ahead of the project.

The Cost of Operating Without a Valid Determination

An expired AJD doesn’t by itself put you in violation, but it does mean you’re working without a clear picture of where regulated waters sit on your property. That’s the exact scenario where accidental fill violations happen.

Filling, grading, or otherwise disturbing wetlands without a valid Section 404 permit can trigger federal enforcement. The Clean Water Act authorizes civil penalties of up to $25,000 per day for each violation.⁵ After inflation adjustments, that figure now reaches $68,446 per day.⁶

Fines are often the smaller problem. EPA can require you to remove all fill material and restore the site to its original condition, including replanting native species and removing invasives.⁷ Restoration projects have success criteria set case by case, such as 80% survival of planted native species after the first year and 100% survival in subsequent years. Monitoring periods typically run five to ten years, all at your expense. A stale delineation is cheap to fix. That combination is not.

1
U.S. Army Corps of Engineers. Regulatory Guidance Letter 16-01 – Jurisdictional Determinations
2
U.S. Army Corps of Engineers. Jurisdictional Determinations and Delineating Waters of the United States
3
Supreme Court of the United States. Sackett v. EPA, 598 U.S. 651
4
U.S. Environmental Protection Agency. Updated Definition of Waters of the United States
5
Office of the Law Revision Counsel. United States Code Title 33 – 1319
6
Federal Register. Civil Monetary Penalty Inflation Adjustment Rule
7
U.S. Environmental Protection Agency. How Enforcement Actions Protect Wetlands Under CWA Section 404