NWP 33Effective 2026-03-15

Temporary Construction, Access, and Dewatering

Requirements at a Glance

  • Pre-Construction Notification (PCN) is required for all activities
  • Authorized under Section 10 and Section 404
  • The primary activity must be authorized by the Corps or U.S. Coast Guard
  • Pre-Construction Notification (PCN) is mandatory for all activities
  • Temporary fills must be removed in their entirety upon project completion
  • Affected areas must be restored to pre-construction elevations
  • Must use appropriate measures to maintain near-normal downstream flows
  • Cofferdams must be designed to withstand expected high flows

Purpose & Scope

Nationwide Permit 33 authorizes temporary structures, work, and discharges of dredged or fill material, such as cofferdams, that are necessary for construction activities, access to project sites, or dewatering of construction areas. This permit is unique because it provides the necessary authorization for the temporary 'logistics' of a project, provided the primary activity itself is already authorized by the Corps or the U.S. Coast Guard. The scope of this permit includes both Section 10 navigable waters and Section 404 discharges. It is designed to facilitate the practical side of aquatic construction, allowing for the placement of temporary fill for equipment access or the creation of dry work environments, as long as the site is restored to its original condition once the primary work is finished.

What Changed in 2026

The 2026 reissuance of NWP 33 maintains the same national terms and conditions as the 2021 version with no substantive modifications. The Corps reevaluated the permit's use and determined that the existing requirement for mandatory pre-construction notification (PCN) for all activities remains a sufficient safeguard to ensure that temporary impacts do not result in more than minimal adverse environmental effects. While the regulatory text is unchanged, the supporting decision document was updated to include current environmental baseline data. This update utilizes the most recent national-scale assessments, such as the 2022 National Lakes Assessment and the 2021 National Wetland Condition Assessment, to support the Corps' finding that the cumulative effects of these temporary activities remain minimal nationwide.

Who Needs This Permit?

Compliance managers, general contractors, and civil engineers overseeing aquatic infrastructure projects need this permit. It is the go-to authorization for anyone needing to build a cofferdam, a temporary work bridge, or an access pad to complete a larger permitted project in or near the water.

Common Project Types

  • Installation of a cofferdam to dewater a bridge pier work area
  • Placement of temporary gravel pads for crane access in a wetland
  • Construction of temporary work trestles for utility line installation
  • Temporary dewatering of a canal for maintenance repairs
  • Discharge of temporary fill for construction vehicle access routes
  • Placement of temporary bypass structures for stream work

Environmental Review

The Corps determined that the reissuance of NWP 33 has 'no effect' on federally-listed endangered or threatened species or their critical habitat. This finding is anchored by General Condition 18, which requires project-specific Section 7 consultation if a temporary activity 'might affect' listed resources; authorization is only granted once this process is complete. Compliance with Section 106 of the National Historic Preservation Act is ensured through General Condition 20. Because every project under NWP 33 requires a PCN, district engineers are able to review each temporary layout for potential impacts to historic properties. For Essential Fish Habitat (EFH), district engineers can apply regional conditions to ensure that temporary dewatering or access fills do not disrupt sensitive aquatic life cycles.

Frequently Asked Questions

Do I need to submit a PCN for temporary access fills under NWP 33?

Is there a limit on how much temporary fill I can place?

Can I use NWP 33 if my main project doesn't have a permit yet?

What happens if I can't restore the site to original elevations?

Does this permit cover the dredging needed for a cofferdam?

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