United States Department of Agriculture 554-CPS-1

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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. 

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Natural Resources Conservation Service 

CONSERVATION PRACTICE STANDARD 

DRAINAGE WATER MANAGEMENT 

CODE 554 

(ac)

DEFINITION 

The process of managing the drainage volume and water table elevation by regulating the flow from a

surface or subsurface agricultural drainage system. 

PURPOSE 

This practice is used to accomplish one or more of the following purposes: 

• Reduce nutrient, pathogen, and pesticide loading from drainage systems into downstream receiving

waters. 

• Improve productivity, health, and vigor of plants. 

• Reduce oxidation of organic matter in soils. 

CONDITIONS WHERE PRACTICE APPLIES 

This practice is applicable to agricultural lands with surface or subsurface agricultural drainage systems

that can be adapted, or are partially adapted, to allow management of drainage volume and water table by

changing the elevation of water level at the outlets. 

This practice applies where a high natural water table exists or has existed, and the topography is

relatively smooth, uniform, and flat to very gently sloping. 

The practice applies to saline or sodic soil conditions, but special considerations are required. See Qadir

and Oster 2003 in the References section. 

This practice does not apply to the management of irrigation water supplied through a subsurface

drainage system. For that purpose, use NRCS Conservation Practice Standards (CPSs) Irrigation System,

Surface and Subsurface (Code 443) and Irrigation Water Management (Code 449). 

The practice does not apply to the seasonal inundation of fields from overland surface runoff. 

CRITERIA 

General Criteria Applicable to All Purposes 

Manage the drainage discharges and water levels in a manner that does not cause adverse impacts to

other properties or drainage systems. Water control structures used in the management system must not

cause water to back up into a main or lateral beyond a property line unless the upstream landowner has

given written permission. 

Manage gravity drainage systems by adjusting the outlet elevations of the water control structures located

within the drainage system, either manually or by utilizing automation technology. Refer to NRCS CPS

Structure for Water Control (Code 587) for design criteria. Managed drainage mode is raising the elevation
of the control structure outlet above the normal drain elevation to store water in the soil, as opposed to

free drainage mode. 

Manage pumped drainage outlets by adjusting the on-off elevations for pump cycling throughout the year

to provide the required outlet elevation for the drainage system. 

Raising the outlet elevation of a water control structure in a flowing drain must result in an elevated free

water surface within the soil profile. 

Locate structures and pumps where they are convenient to operate and maintain. When operated in free

drainage mode, water control structures, including any buried in-line control valves, must require no more

than 0.2 feet of head to maintain the unrestricted flow rate of the drainage system. 

Ensure the flow velocity in the drainage system does not exceed acceptable velocities prescribed by

NRCS CPSs Surface Drain, Main or Lateral (Code 608) and Subsurface Drain (Code 606), as applicable.

Controlling drain velocities is typically necessary only during the release of drainage water from control

structures. 

In cold climates, lower the outlet elevation during winter after drain flow has stopped. This will avoid

freezing damage to the water control structures. Raise the water to the planned elevation when flow

resumes. 

Control elevation 

Reference the outlet elevation of each water control structure to a “control elevation” which is defined as

the lowest elevation of the soil surface in the field (control zone) impacted by the operation of the water

control structure. 

To determine the area drained by a single drain use the lateral spacing recommendations specified in the

state drainage guide for the predominant soil type in the drained field. The outer boundary of the drained

area is a distance of one-half the recommended lateral spacing away from the drains. 

Where a state drainage guide does not exist, determine the lateral drain spacing using the van

Schilfgaarde equation and associated State-accepted time factor. 

Control zone 

The control zone (or impacted area) for each water control structure is defined as the drained area

upstream of the given control structure. The control zone is bounded on the lower end by the planned

control elevation of the given water control structure and on the upper end by the control elevation of the

structure immediately upstream or a defined elevation above the given control structure, whichever is less.

The defined elevation is a maximum of 2 feet. 

Develop a management calendar which specifies the target water control structure outlet elevation

throughout the year to meet the intended purpose. Adjust the water levels throughout the year to allow for

proper root zone development. Specify conditions where adjusting the outlet elevations may be required,

such as significant rainfall events. Describe what those adjustments might be. Provide means for the

operator to monitor and record the water levels in the water control structures and the water table within

the control zones. This information will enable the operator to adapt management to changing weather

conditions and minimize adverse effects on crops and soils. 

Laws and regulations 

Plan, design, and construct this practice to comply with all Federal, State, Tribal, and local laws and

regulations 

Additional Criteria to Reduce Nutrient, Pathogen, and Pesticide Loading 

NRCS CPS Drainage Water Management (Code 554) is an ongoing practice implemented throughout all

days of the year. 

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Minimize drainage below that is necessary to provide an adequate root zone for the crop. 

Maintain each water control structure outlet in managed drainage mode except when the water table must

be lowered for trafficability for field work, adverse weather conditions, or system maintenance. 

Raise the outlet elevation of the water control structure to within 12 inches or less of the ground surface

during noncropped (fallow) periods. Raise the outlet within 2 weeks after final field operations following

harvest. Change to free drainage mode no more than 2 weeks before the planned commencement of the

next season’s field operations, except during system maintenance periods or to provide trafficability when

field operations are necessary. 

In cold climates, lower the outlet elevation during winter after drain flow has stopped. This will avoid

freezing damage to the water control structures. Raise the water to the planned elevation when flow

resumes. In fields with winter cover crops, lower the outlet elevation during winter to within 0.5 feet of the

expected cover crop rooting depth. 

Raise the outlet elevation of the water control structure to within 0.5 feet below the control elevation or just

below the root zone of an actively growing crop prior to and during applications of liquid or solid manure,

soluble fertilizers, or concentrated organic fertilizersin order to prevent direct leakage of manure and limit

transport of soluble nutrients into drainage pipes through soil macro pores (cracks, wormholes, root

channels). Maintain the raised outlet elevation for at least 15 days following manure or fertilizer application

or until the next precipitation event that produces drainflow. Monitor the control structures for trapped

manure. Remove liquid manure trapped in the structures and dispose of it in an appropriate manner. 

Manure, fertilizer, and waste by-product applications shall be in accordance with NRCS Conservation

Practice Standards, Nutrient Management (Code 590) and Waste Recycling (Code 633). 

Additional Criteria to Improve Productivity, Health, and Vigor of Plants 

When managing drainage outflow to maintain water in the soil profile for use by crops or other vegetation,

specify the water elevation based on root depth and soil type to maintain proper root development and soil

aeration. 

Raise the outlet elevation after planting to allow the retention and movement of water in the crop root

zone. 

Additional Criteria to Reduce Oxidation of Organic Matter in Soils 

Minimize drainage beyond that necessary to provide an adequate root zone for the crop. 

To reduce oxidation of organic matter, set the outlet elevation to enable the water table to rise to the

ground surface, or to a designated maximum elevation, for sufficient time to create anaerobic soil

conditions. The implementation of this practice must result in a reduced average annual thickness of the

aerated layer of the soil. 

CONSIDERATIONS 

When planning, designing, and installing this practice, consider— 

• Generally, the same drainage intensity is not required at all times during the year. Consider a

management strategy that enhances crop yield while minimizing negative water quality impacts. 

• For the practice to be economical and practical, each control structure needs to influence a

significant amount of the field; therefore, drainage water management is generally limited to nearly

flat fields with slopes typically less than 1.0 percent. On moderate slopes, design drainage laterals

on the contour to maximize the control zone of each structure. Raising the water table during the

growing season will generally increase evapotranspiration and may increase crop yield. Take care

to maintain a sufficiently aerated crop root zone so as not to damage the crop. 

• Monitoring of root zone development may be necessary if the free water surface in the soil profile

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rises close to the soil surface during the growing season. 

• Because of the increase in water volume stored in the soil profile, drainage water management may

affect the water budget, especially volumes and rates of runoff, infiltration, evaporation,

transpiration, deep percolation and ground water recharge. 

• Drainage water management may increase base flow in streams and ditches because of a higher

gradient from the fields. A higher field water table may increase lateral and vertical seepage losses.

Since this water will likely pass through reduced (low) oxygen zones, seepage water may be

denitrified before reaching surface water conduits. 

• Installing inexpensive water table observation wells can improve management. 

• Avoid traffic on fine-textured, wet soils to minimize soil compaction. 

• Reducing mineralization of organic soils may decrease the release of soluble phosphorus, but

water table management may increase the release of soluble phosphorus from mineral soils. 

• Elevated water tables may increase the runoff portion of outflow from fields. Consider conservation

measures that control sediment loss and associated agrichemical discharge to waterways. 

• When using this practice for reduction of pesticide loading or rodent control, apply pesticide in

accordance with NRCS CPS Integrated Pest Management (IPM) (Code 595). 

• If wildlife habitat is a resource concern, design the system so that during the noncropped season,

the managed elevation of the drainage outlet is consistent with the habitat management plan for the

targeted species. 

PLANS AND SPECIFICATIONS 

Prepare plans and specifications that describe the requirements for applying the practice to achieve its

intended purposes. 

At a minimum, include— 

• Farm and field information with a location map. 

• The objectives of the landowner. 

• A map (or maps) that includes— 

• Field boundaries. 

• Drainage water management project area (drained area) boundaries. 

• A soils map showing the drainage class. 

• A map of the drainage system, including the location of water control structures and the size

and location of all mains and laterals. 

• A topographic map with 1-foot contours or less. 

• A map that shows the location, size, and impacted area (i.e., control zone) of each existing and

planned control structure. 

• A management plan as described in the Operation and Maintenance section of this standard. 

OPERATION AND MAINTENANCE 

Prepare an operation and maintenance (O&M) plan and review with the landowner or operator

responsible for the application of this practice. 

• Identify the intended purpose of the practice, safety requirements, and critical dates and target

elevations of the water table necessary to meet the intended purposes. 

• Include instructions for operation and maintenance of critical components of the drainage

management system, including instructions necessary to maintain flow velocities within allowable

limits when lowering water tables. Address the following management objectives as applicable: 

• Prior to tillage, harvest, and other field operations, set the outlet elevation at a depth to provide

trafficability throughout the field (typically the bottom of the drainage outlet). 

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• After planting and other necessary field operations, raise the outlet elevation to the planned

level. Monitor water elevations to allow capacity to store infiltration from rainfall, as well as

subsurface water from up gradient, depending on the soil texture, significant allowance may be

required to allow for capillary rise. This will vary, depending on crop, stage of growth, and soil. 

• Operate the outlet elevation in the control structure during the crop season so that prolonged

saturation of the root zone does not occur (i.e., as observed in the water table observation

wells, if any). 

• During the fallow period, set the outlet elevation in the control structure to allow local ground

water and infiltrated precipitation to elevate the water table to potentially rise near the soil

surface or to an elevation specified by the planner. 

• To prevent leakage of liquid manure applications into drainpipes, specify the elevation of the

raised drainage outlet and the number of days prior to and after the application that a raised

outlet elevation is to be maintained. 

• Replace warped flashboards and damaged seals that cause structure leakage. 

REFERENCES 

Qadir, M. and J.D. Oster. 2003. Crop and irrigation management strategies for saline-sodic soils and

waters aimed at environmentally sustainable agriculture. Science of The Total Environment. DOI:

10.1016/j.scitotenv.2003.10.012. Volume 323, Issues 1–3, 5 May 2004, Pages 1–19. 

USDA, NRCS. 2001. National Engineering Handbook (Title 210), Part 624, Sec 10, Water table control,

and Sec. 16, Drainage of agricultural land. Washington, D.C. https://directives.sc.egov.usda.gov/.

USDA, NRCS. 2001. National Engineering Handbook (Title 210), Part 650, Engineering Field Handbook,

Chapter 14, Water management (Drainage). Washington, D.C. https://directives.sc.egov.usda.gov/.

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