How do I know if I need a Section 404 permit?

You need Clean Water Act Section 404 authorisation if your project discharges dredged or fill material into waters of the United States. If the impact is small enough and matches a listed activity, a nationwide permit may authorise it. If not, you need an individual permit. This tool screens your impacts against all 57 nationwide permits.

When did the 2026 nationwide permits take effect?

The 2026 nationwide permits were published at 91 FR 768 on 2026-01-08, took effect on 2026-03-15, and expire on 2031-03-15.

Does the 300 linear foot stream limit still apply?

No. The 300 linear foot limit on the loss of stream bed was removed in the 2021 reissuance and the Corps declined to reinstate it in 2026. Acreage limits still apply.

91 FR 768 · effective 2026-03-15

Find out which nationwide permit covers your project, and see the rule that says so.

Every other answer on the open web is a PDF, a page of statute, or an instruction to call your district office. Whether you need a wetland permit, and which Section 404 pathway it falls under, is a question about thresholds. PermitBird screens your impacts against all 57 nationwide permits and returns a pathway, the notification trigger, and the rule text behind each conclusion.

Run a determination Use the API

Permits compiled: 57 of 57; every one sourced to the final rule
Carrying acreage limits: 20; the rest state no acreage cap
District conditions: 0 of 38; not yet compiled, and we say so
State 401 certifications: 0 of 54; not yet compiled, and we say so

Determination

The full engine, running in your browser. Change a number and the verdict updates with the rule that produced it.

Your project

Everything runs in this browser. Nothing is sent to a server.

Activity

Aquatic resource

Permanent loss

Stream bed

USACE district

State or territory

Screening only. Only a Corps district can confirm that a nationwide permit authorises your project.

Live preview

Nationwide permit, notification required

A nationwide permit looks available, but you must file a pre-construction notification before you build.

Computed against the 2026 nationwide permits, effective 2026-03-15.

Pre-construction notification

Required. The district engineer has 45 calendar days to review a complete notification.

Permanent loss is greater than 0.1 acres, which triggers a pre-construction notification.
Verified
0.35 acres measured against the 0.1 acres notification trigger.
91 FR 768 - Reissuance and Modification of Nationwide Permits (final rule, 8 Jan 2026)
NWP 14 requires notification in defined circumstances. Check them against your project.
Verified
PCN required if: (1) the loss of waters of the United States exceeds 1/10-acre; or (2) there is a discharge in a special aquatic site, including wetlands.
91 FR 768 - Reissuance and Modification of Nationwide Permits (final rule, 8 Jan 2026)
NWP 3 requires notification in defined circumstances. Check them against your project.
Verified
Required for activities under paragraph (b) - removal of accumulated sediments and debris outside the immediate vicinity of existing structures.
91 FR 768 - Reissuance and Modification of Nationwide Permits (final rule, 8 Jan 2026)

Permits screened (3)

NWP 14: Linear Transportation ProjectsWithin limits

Permanent loss is within the 1/2 acre limit NWP 14 applies in non-tidal waters.
Verified
0.35 acres of permanent loss in non-tidal waters, measured against the 1/2 acre limit. 1/2-acre limit applies in non-tidal waters; a lower 1/3-acre limit applies in tidal waters.
91 FR 768 - Reissuance and Modification of Nationwide Permits (final rule, 8 Jan 2026)

NWP 3: MaintenanceNot determinable

No impact limit has been transcribed for NWP 3 yet, so eligibility cannot be determined here.
Unverified
PermitBird returns an explicit gap rather than an inferred limit. Read the permit text or contact the district office.
91 FR 768 - Reissuance and Modification of Nationwide Permits (final rule, 8 Jan 2026)

NWP 18: Minor DischargesExceeds limits

Permanent loss exceeds the 1/10 acre limit for NWP 18.
Verified
0.35 acres of permanent loss measured against a 1/10 acre limit.
91 FR 768 - Reissuance and Modification of Nationwide Permits (final rule, 8 Jan 2026)

Sacramento District

Regional conditions are not compiled. This determination covers the federal layer only.

District regulatory office

California Section 401

Section 401 certification conditions are not compiled. Confirm with the state agency.

What we hold for this state

What this determination does not cover

The mapping from "Road, highway or railway crossing" to candidate permits is unverified. Confirm the permit selection against the permit text.
Impact limits are not yet transcribed for NWP 3.
Regional conditions for the Sacramento District are not compiled. They can narrow or remove a nationwide permit, so confirm them with the district before relying on this.
The Clean Water Act Section 401 water quality certification for California is not compiled. A state can condition, waive or deny certification, which changes the outcome.

Read the full coverage matrix

Sources

Project impact entered: 0.35 acres permanent loss, 120 linear feet of stream bed.

Gaps are shown, not hidden

We hold the federal layer in full. We do not yet hold the 38 districts' regional conditions or the 54 state Section 401 certifications, and every determination says so rather than implying full coverage. A regulatory product that quietly guesses is worth less than none.

Coverage and method

Three things engineers still get wrong

The 300 linear foot stream limit is no longer in force. It was removed in 2021 and was not reinstated.
The half acre limit is not universal. NWP 14 is 1/3 acre in tidal waters, and NWPs 46 and 60 use one acre.
General Condition 32 has two clocks: 30 days to judge completeness, then 45 to review.

Read the guides

Built for agents too

A JSON API, a hosted MCP server, an OpenAPI manifest and machine readable pricing. The sandbox key is public, so an agent that finds this page can make a successful call without signing up.

curl https://permitbird.com/api/v1/nwp/14 \
  -H "Authorization: Bearer pb_sandbox_publickey"

API documentation