Cypress Environment & Infrastructure delineates wetlands in Louisiana and carries the result through the U.S. Army Corps of Engineers (USACE) jurisdictional determination (JD) and the federal and state permits that follow. This page covers what is specific to Louisiana: which Corps district reviews your site, how the coastal zone changes the permit path, and how compensatory mitigation is calculated.

For general background, see our pages on wetland delineation, jurisdictional determinations, Section 404 permits, and types of environmental permits.

Which Corps District Reviews a Louisiana Site

The New Orleans District (MVN) administers the Corps regulatory program in southern Louisiana, but it is not the only district with Louisiana territory. District boundaries follow river basins, not parish lines. Based on the USACE Regulatory Areas of Responsibility map layer:

New Orleans District: the coastal parishes, the Atchafalaya Basin, Acadiana, the Baton Rouge area, and most of the Florida Parishes, including Lafayette, East Baton Rouge, Jefferson, Orleans, Terrebonne, Lafourche, Plaquemines, and Tangipahoa, and most of Calcasieu and Cameron.
Vicksburg District (MVK): north Louisiana (the Red River, Ouachita, and Tensas drainages), including Caddo, Bossier, Ouachita, Lincoln, Natchitoches, Grant, Winn, and the river parishes from East Carroll to Concordia, plus parts of Rapides and Avoyelles. Vicksburg also has the Pearl River drainage, which covers most of Washington Parish and the eastern part of St. Tammany Parish.
Galveston District: the Sabine River side of Calcasieu, Cameron, Beauregard, and Vernon Parishes, including the Sabine Pass area.
Fort Worth District: the Toledo Bend and upper Sabine drainage, which covers most of Sabine Parish and about half of De Soto Parish.

St. Tammany, Rapides, Avoyelles, De Soto, Sabine, and Vernon are all split between districts. Check the parcel against the district jurisdiction maps on the New Orleans District and Vicksburg District regulatory pages before filing. A request sent to the wrong district has to be transferred before review starts.

Wetland Delineation in Louisiana

Delineations follow the 1987 Corps of Engineers Wetland Delineation Manual and the Atlantic and Gulf Coastal Plain Regional Supplement (Version 2.0, ERDC/EL TR-10-20). Louisiana spans three of the supplement’s subregions: the Mississippi Alluvial Valley (LRR O), the Inner Coastal Plain (part of LRR P), and the Outer Coastal Plain (LRR T). Some hydric soil and hydrology indicators apply only in certain subregions, so the subregion is recorded on every data form.

Field conditions that most often complicate Louisiana delineations:

Dry-season visits. The supplement treats late spring and summer as the normal dry season and names wet pine flats in western Louisiana, Louisiana coastal prairies, and Mississippi Alluvial Valley bottomland hardwoods among the wetland types that can dry out completely. A summer visit can miss hydrology indicators that are obvious in winter. When that happens, the supplement’s Chapter 5 procedures for wetlands that periodically lack hydrology indicators apply.
FACU-dominated wetlands. In some coastal plain wetlands the dominant plants are rated FACU, especially in dry periods when upland annuals move in. Hydrophytic vegetation then has to be shown with the supplement’s problematic-vegetation procedures, not the dominance test alone.
Growing season. When the hydrology call depends on observed saturation or monitoring data, growing-season dates are set from on-site plant activity (bud burst, new growth) or soil temperature, as the supplement specifies.
Altered hydrology. Levees, forced drainage, spoil banks, and canals change how water moves across a site. The report documents those alterations and explains how they affect each boundary.

Our Delineation Process

Desktop review. NWI mapping, FEMA flood zones, NRCS soil survey data, topographic data, and current and historical aerial imagery, plus the Corps district boundary and the state coastal zone boundary, so the permit path is known before fieldwork.
Field assessment. Vegetation, soils, and hydrology are documented at paired sample points on both sides of each boundary using the Atlantic and Gulf Coastal Plain data form.
Boundary flagging and GPS survey. Wetland limits are flagged in the field and recorded with sub-meter GPS, then mapped in GIS against the project footprint.
Delineation report. Maps, data forms, photographs, and conclusions, formatted for the district that has the site, with notes on tidal waters, the coastal zone, and other permit triggers.
JD and permit support. When needed, we submit the delineation to the Corps with a request for an approved or preliminary JD, or with the permit application.

Jurisdictional Determinations: AJD or PJD

A delineation maps wetlands and other aquatic resources. A JD is the Corps’ position on which of them are waters of the United States. An approved JD (AJD) is a binding determination and is generally valid for five years under Regulatory Guidance Letter 05-02. A preliminary JD (PJD) treats the mapped resources as jurisdictional so a permit can proceed; it cannot be used to show that a feature is not jurisdictional. The Corps does not publish a fixed turnaround, but a PJD is usually faster. See our jurisdictional determination page for detail.

Which definition applies. The January 2023 definition of waters of the United States is enjoined in Louisiana, so the Corps and EPA apply the pre-2015 regulatory regime here, interpreted consistently with Sackett v. EPA (2023). The September 2023 conforming rule does not govern Louisiana sites (EPA rule status page). Under Sackett, an adjacent wetland is jurisdictional only if it has a continuous surface connection to a relatively permanent, jurisdictional water, and the agencies’ March 2025 guidance reads that connection narrowly. A replacement rule was proposed on November 20, 2025, with a supplemental proposal on September 9, 2026; neither is final. See what the Sackett ruling changed.

In practice. Most of coastal Louisiana is tidal marsh and swamp that abuts tidal waters, and Sackett changes little there. The question becomes site-specific for depressional wetlands and pine flats in western and central Louisiana, and for wetlands inside leveed, pumped drainage systems, where the answer turns on the actual surface connection in the field. An AJD is worth its longer schedule when a non-jurisdictional finding would change the site plan. See also isolated wetlands.

Permits: Federal, State, and Coastal

Corps authorization

Small fills are usually authorized under a nationwide permit (NWP). The 2026 NWPs took effect on March 15, 2026 and expire on March 15, 2031 (91 FR 768). Each district adds its own regional conditions, so read the New Orleans or Vicksburg District conditions for your site before relying on an NWP. Projects that exceed NWP limits need an individual permit with public notice. Work in or over navigable waters also needs Section 10 authorization; in tidal waters, Section 10 jurisdiction extends to the mean high water line.

LDEQ Section 401 water quality certification

The Louisiana Department of Environmental Quality (LDEQ) issues Section 401 Water Quality Certifications for federal permits that may result in a discharge into waters of the United States. The New Orleans District notes that this includes placing dredged or fill material in wetlands and mechanized clearing of wetlands. For an NWP, check LDEQ’s certification decision for that specific NWP before assuming it is covered.

Coastal Use Permit (CUP)

Inside the Louisiana Coastal Zone, most regulated work also needs a Coastal Use Permit under the State and Local Coastal Resources Management Act. Since October 1, 2025, CUPs have been handled by the Office of Permitting and Compliance of the Louisiana Department of Conservation and Energy (C&E), the renamed Department of Energy and Natural Resources, which absorbed the permitting role of the former Office of Coastal Management. A single joint permit application filed through C&E goes to both the state and the New Orleans District.

The coastal zone runs from the Texas line through Cameron and Calcasieu, across Vermilion, Iberia, St. Mary, St. Martin, Terrebonne, and Lafourche, north to St. Charles, St. John the Baptist, and St. James, and east through Livingston, Tangipahoa, and St. Tammany. Orleans, Jefferson, St. Bernard, and Plaquemines are inside it. The inland boundary cuts through several of these parishes, so check the parcel against the state’s coastal zone map.

Exemptions. Under La. R.S. 49:214.34, activities wholly on land five feet or more above mean sea level, or within fastlands, generally do not need a CUP unless the state finds a direct and significant impact on coastal waters. C&E maintains maps of these areas.
Federal jurisdiction is not the trigger. The CUP is a state permit. A wetland the Corps finds non-jurisdictional can still require a CUP and state compensatory mitigation, and CUP mitigation must come from options the state accepts, which is not every Corps-approved bank. See our 401 and coastal permit overview.
Local programs. Twelve parishes run approved Local Coastal Management Programs and permit uses of local concern themselves: Calcasieu, Cameron, Jefferson, Lafourche, Orleans, Plaquemines, St. Bernard, St. Charles, St. James, St. John the Baptist, St. Tammany, and Terrebonne.

Other state reviews

State water bottoms. The state owns the beds of many waterways, generally to the low-water line on rivers and streams and to mean high water on most lakes, bays, and sounds. Work on state water bottoms is coordinated with the State Land Office.
Scenic rivers. The Louisiana Department of Wildlife and Fisheries issues Scenic Rivers permits for activities such as crossings, bulkheads, and other structures on streams in the Natural and Scenic Rivers System, which includes the Tchefuncte and Bogue Chitto rivers.
Listed species. The gopher tortoise is federally listed as threatened in Louisiana. When a Corps permit is involved, listed species and critical habitat are addressed through ESA Section 7 consultation. See gopher tortoise surveys.

Compensatory Mitigation, Including Streams

New Orleans District. Wetland impacts and credits are calculated with the Louisiana Wetland Rapid Assessment Method (LRAM), released for use in the district on February 29, 2016 to replace the Modified Charleston Method. The district does not use a separate stream method. Streams are treated as part of the overall wetland feature, so stream impacts are assessed and mitigated with the associated wetland, typically through LRAM.
Vicksburg District. North Louisiana sites fall under the Vicksburg District, which uses the Modified Charleston Method for stream mitigation. The district posts the 2010 Charleston Method guidelines, which include the stream credit worksheets. In either district, confirm current practice at the pre-application meeting.
State CUP mitigation. Coastal zone impacts carry a separate state mitigation requirement, evaluated and approved by C&E rather than by the Corps.

Approved banks and their service areas are listed in the Corps’ RIBITS database. See our pages on mitigation banking, stream mitigation, and buying credits versus establishing a bank.

Louisiana Landscapes and What They Mean for Fieldwork

Deltaic marsh and swamp. In the Pontchartrain Basin, the Barataria and Terrebonne basins, and the Atchafalaya Basin, tidal marsh grades into cypress-tupelo swamp and bottomland hardwood forest. Wetland boundaries here are often clear; more of the work is documenting tidal waters, the Section 10 line, and the coastal zone.
Chenier Plain and coastal prairie. In southwest Louisiana, low ridges separate broad marshes, and remnant coastal prairie wetlands can look like upland grassland in summer. Sites near the Sabine River may belong to the Galveston District.
Bottomland hardwoods. Along the Atchafalaya, Red, Ouachita, and Mississippi Rivers, floodplain forests in the Mississippi Alluvial Valley (LRR O) can lack surface water for months. Soils and hydrology indicators specific to LRR O carry much of the decision.
Florida Parishes uplands. North of Lake Pontchartrain, pine flats, seepage areas, and higher-gradient streams bring the vegetation and stream mitigation questions above, along with gopher tortoise habitat and the split between the New Orleans and Vicksburg Districts.

Louisiana Project Experience

Cypress has performed wetland delineations in Louisiana. We are licensed in Louisiana and serve Louisiana projects from our Biloxi headquarters; we do not keep a Louisiana office. Louisiana work includes:

Lea Farm Mitigation Bank. A proposed East Baton Rouge Parish, Louisiana mitigation bank producing bottomland hardwood credits on a former agricultural site. Wetland delineation, endangered species survey and wetland ecological assessments on 400+ acres.
Mei Gum Mitigation Bank. A pending Tangipahoa Parish, Louisiana mitigation bank producing bottomland hardwood credits on a former silviculture site. Wetland delineation, endangered species survey, wetland ecological assessment and mitigation banking instrument on 300+ acres.
Bedico Creek site. 505-acre wetland delineation, endangered species survey and wetland function assessment in Tangipahoa Parish.
Louisiana Coastal Area 4 Restoration Planning. Planning program support to the New Orleans District on the LCA 4 group, the four projects authorized by WRDA 2007 Section 7006(e)(1). Cypress supported preparation of the Summary Reports for two of them: Maintain Land Bridge between Caillou Lake and the Gulf of Mexico, and Stabilize Gulf Shoreline at Point Au Fer Island.
Louisiana Coastal Area 6 Restoration Program. Restoration program support to the New Orleans District on the LCA 6 group, the six projects authorized by WRDA 2007 Section 7006(e)(3), in partnership with Malcolm Pirnie/Arcadis, including the Summary Report for the six-project feasibility study. The group includes Convey Atchafalaya River Water to Northern Terrebonne Marshes (our Northern Terrebonne Marsh Restoration page) and the Amite River Diversion Canal Modification in Ascension and Livingston Parishes.

On private sites we coordinate the delineation with mitigation planning, permitting, and civil design.

Frequently Asked Questions About Wetland Delineation in Louisiana

Is a wetland delineation required before I build in Louisiana?

If the site has wetlands or other waters and your work will place fill in them, the Corps needs mapped boundaries to process a permit, and C&E needs them for a Coastal Use Permit inside the coastal zone. If you are not sure whether wetlands are present, a delineation answers that before design is fixed.

How do I know if wetlands are present on my property?

Many Louisiana wetlands are not wet year-round, and NWI mapping is not drawn at site scale. A field delineation documents vegetation, soils, and hydrology at sample points to fix the boundary.

How long is a wetland delineation or JD valid in Louisiana?

An approved JD is generally valid for five years under Regulatory Guidance Letter 05-02, unless new information warrants revision. A delineation report or PJD has no fixed federal expiration, but the district may ask for updated data if site conditions or the regulations have changed. We can update or re-verify older reports.

Can Cypress request a jurisdictional determination for me?

Yes. After fieldwork and reporting, we submit the delineation to the New Orleans, Vicksburg, Galveston, or Fort Worth District, whichever has the site, with a request for an approved or preliminary JD, depending on whether you need a binding answer or a faster path to a permit.

If the Corps says a wetland is not jurisdictional, do I still need a permit?

Possibly. Inside the coastal zone, a Coastal Use Permit can still apply. Scenic Rivers permits, state water bottom authorizations, local coastal programs, and parish floodplain and drainage rules are separate from federal jurisdiction.

Do Louisiana parishes have their own requirements?

Yes. The twelve parishes with approved Local Coastal Management Programs (including Jefferson, St. Tammany, Terrebonne, and Orleans) permit uses of local concern, and parishes also apply their own floodplain, drainage, and subdivision rules. Drainage Districts are frequently a key stakeholder on mitigation projects. We confirm local requirements and coordinate with the relevant local government entities as part of the permit plan.

Request Wetland Delineation in Louisiana

Send the parcel location, acreage, and what you plan to build. We will tell you which Corps district and state programs apply, and whether you need a delineation and JD.

Call us at: 228-596-1580
Email: [email protected]

Offices: 772 Howard Avenue, Biloxi, MS (headquarters); 150 Government Street, Suite 950-1000, Mobile, AL; and 13 Palafox Place, Pensacola, FL. Hours are Monday–Friday, 9 a.m.–5 p.m.

Wetland Delineation, JDs and Permitting in Louisiana