United States Department of Agriculture 657-CPS-1

NRCS, NHCP

January 2024

Notice of Proposed Changes to the National Handbook of Conservation Practices 

for the Natural Resources Conservation Service

[Docket No. NRCS-2023-0022]

PROPOSED FULL TEXT FOR PRACTICE STANDARD CODE 657

NRCS reviews and periodically updates conservation practice standards. To obtain the current 

version of this standard, contact your Natural Resources Conservation Service State office or 

visit the Field Office Technical Guide online by going to the NRCS website at 

https://www.nrcs.usda.gov/ and type FOTG in the search field. 

USDA is an equal opportunity provider, employer, and lender.

Natural Resources Conservation Service 

CONSERVATION PRACTICE STANDARD 

WETLAND RESTORATION 

CODE 657 

(ac)

DEFINITION 

The re-establishment of abiotic conditions (e.g., hydrology, topographic features, and substrate) on

partially, effectively, or fully drained wetlands to a close approximation of pre-disturbance abiotic

conditions. 

PURPOSE 

Address identified resource concerns (e.g., water quality degradation, inadequate habitat for wildlife, or

degraded plant condition) by restoring the original abiotic conditions to an area that was once an

undisturbed and naturally occurring wetland. 

CONDITIONS WHERE PRACTICE APPLIES 

This practice applies to any land use (i) where there was once a naturally occurring wetland, (ii) the

wetland has been altered by onsite actions or offsite actions or disturbances that changed the hydrology

and other abiotic features, and (iii) where the conservation objective is to restore the area to a close

approximation of the pre-disturbance wetland conditions. 

Many disturbed wetlands historically contained a mosaic of landscape features, including some small nonwetlands (e.g., pimple mounds, mima mounds, gilgai uplifts, irregular sediment deposition in floodplains)

making it impracticable to separate (delineate) these areas from the historic wetland areas. In such

situations, wetland restoration will include intermingled non-wetlands, with the objective of replicating the

historic wetland and non-wetland conditions within the project area. 

Commonly supporting practices include, but are not limited to: 

• Conservation Practice Standard (CPS) Dike or Levee (Code 356) or Diversion (Code 362), used to

construct a dike, diversion, berm, or ditch plug. 

• CPS Structure for Water Control (Code 587), used to install a water control structure. 

Common associated practices installed prior to or following installation of this practice include: 

• CPS Wildlife Habitat Planting (Code 420) or Tree and Shrub Establishment (Code 612), used to

restore the plant community. 

• CPS Critical Area Planting (Code 342), used to plant vegetation on areas expected to have high

erosion rates. 

• CPS Wetland Wildlife Management (Code 644), used to manage the habitat. 

• CPS Shallow Seasonal Water Management for Wildlife (Code 646), used to manage shallow water

to mimic natural floodwater pulses. 

• CPS Brush Management (Code 314) or Herbaceous Weed Treatment (Code 315), used to control

undesirable brush or herbaceous species. 
• CPS Forest Stand Improvement (Code 666), used to manage the species composition or density of

existing trees. 

• CPS Prescribed Burning (Code 338), used to restore or manage the plant community, or for site

preparation. 

• CPS Prescribed Grazing (Code 528), used to manage the vegetation with livestock. 

• CPS Structures for Wildlife (Code 649), used to provide abiotic structures for wildlife (e.g., elevated

mounds to provide nesting sites and escape from periods of high water; course woody debris to

provide shelter, basking, and foraging habitat; and nest boxes or platforms). 

This practice does not apply to: 

• Creating a wetland to treat point and non-point sources of water pollution. Use CPS Constructed

Wetland (Code 656). 

• Rehabilitating a degraded wetland, the reestablishment of a former wetland, or the modification of

an existing wetland, where specific wetland functions are augmented beyond the original natural

conditions, at the expense of other functions. Use CPS Wetland Enhancement (Code 659). 

• Creating wetland functions on a site that was not historically a wetland. Use CPS Wetland Creation

(Code 658). 

CRITERIA 

General Criteria Applicable to All Purposes 

The restored wetland will be in the same hydrogeomorphic class and same vegetative modifier as the

historic wetland (USDA NRCS 2008). 

Evaluate sites that are suspected of containing hazardous material. If confirmed, the practice shall not be

installed. 

Identify the project area physical and legal constraints (e.g., property boundaries, flood prevention levees,

public drainage systems, and changes in the watershed) to determine practice feasibility and scope. 

Within the physical and legal constraints, and to the extent practicable, restore hydrology (frequency,

duration, depth, and timing of inundation or saturation), source (e.g., groundwater discharge, overbank

flooding, or tidal inundation), and hydrologic losses (e.g., evaporation, vegetative transpiration,

groundwater recharge, and surface outflow) to the historic conditions by: 

• Removing sediment or fill. 

• Breaking or crushing drainage tile. 

• Breaching or removing berms, dikes, terraces, and levees. 

• Filling pits or ponds. 

• Grading to re-establish macro- or micro-topography. 

• Installing berms or dikes with the application of CPS Code 356. 

• Installing diversions with the application of CPS Code 362. 

• Installing structures for water control with the application of CPS Code 587. 

• Managing frequency, depth, duration, and timing of inundation with the application of CPS Shallow

Seasonal Water Management for Wildlife (Code 646) to mimic natural and historic flood pulses. 

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January 2024
CONSIDERATIONS 

[General Considerations] 

Restoring wetland hydrology to an area may increase or decrease the hydrology to adjacent and

downgradient areas, including adjacent wetlands. 

Some current streams and adjacent areas were historically low-gradient wetlands (Cluer and Thorne

2014). Soil investigations often provide string evidence of the pre-disturbed conditions. 

Excessive excavating and grading activities have the potential to significantly disrupt soil profiles and

facilitate the establishment of noxious and invasive plant species. 

Wetlands attract many species of wildlife. Some can create safety concerns with adjacent roads, airports

and military installations, which may introduce liability concerns to the agency and landowner. 

Restoring the occurrence of elevated areas with lighter textured soils (e.g., sand, sandy loams) removed

during previous land-clearing, leveling, and plowing activities, will restore the plant species diversity and

subsurface nesting sites for an array of small mammals, reptiles, and invertebrates. 

PLANS AND SPECIFICATIONS 

Where applicable, assure water rights support the restoration objectives. 

Describe the past actions that impacted the project area. 

Describe and contrast the historic conditions and current conditions for soils (e.g., presence of aquitards,

wetting and drying cycles), hydrology (e.g., source and hydroperiods) and vegetation (e.g., species

composition, structure, and distribution) associated with the hydrology described. Extrapolate the historic

conditions from a review of aerial photography or other remotely sensed data, soil maps, topographic

maps, stream gage data, similar intact reference wetlands, and historical ecological records. 

Describe the target hydrological conditions and provide an analysis of alternatives that compares different

restoration actions and associated water management actions over the project life. Document alternatives

considered with clear support for the chosen alternative. 

Include a plan view, quantities, and sufficient profiles and cross-sections to define the location, line, and

grade for stakeout, and checkout. 

Identify suitable water sources based on groundwater investigations, stream gage data, water budgeting,

or other appropriate means. 

Identify annual water management practices to be implemented following restoration of the wetland. (e.g.,

CPS Seasonal Water Management for Wildlife (Code 646)). 

OPERATION AND MAINTENANCE 

Operation and Maintenance (O&M) activities may be needed to ensure the continued hydrologic function

of the restored wetland. If needed, a monitoring schedule will be included in the O&M plan. 

The O&M plan may include the following: 

• Maintenance requirements for water control structures, or other structural practices critical to

maintaining the target conditions. 

• Maintenance related to sedimentation. 

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NRCS, NHCP

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January 2024
REFERENCES 

Cluer, B., and C. Thorne. 2014. A Stream Evolution Model Integrating Habitat and Ecosystem Benefits.

River Research and Applications, 30(2) 135-154. 

Maschhoff, Justin T & James H. Dooley. 2003. Functional Requirements and Design Parameters for

Restocking Coarse Woody Features in Restored and Enhanced Wetlands. 

USDA, NRCS. 2008. Hydrogeomorphic Wetland Classification System: An Overview and Modification to

Better Meet the Need of the Natural Resources Conservation Service. Technical Note No. 190-8-76.

February. 

USDA, NRCS. 2011. Scenarios for Wetland Restoration. Technical Note No. 4. October . 

USDA, NRCS. 2021. Wetland Restoration, Enhancement, or Creation, Engineering Field Handbook Part

650, Chapter 13. 160 pp. 

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NRCS, NHCP

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January 2024