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Conservation practice standards are reviewed periodically, and updated if needed. To obtain 

the current version of this standard contact your Natural Resources Conservation Service

State Office, or visit the Field Office Technical Guide.

NATURAL RESOURCES CONSERVATION SERVICE

CONSERVATION PRACTICE STANDARD

SHALLOW WATER DEVELOPMENT AND MANAGEMENT

(Ac.)

CODE 646

DEFINITION

The inundation of lands to provide habitat for 

fish and/or wildlife.

PURPOSE

To provide habitat for wildlife such as 

shorebirds, waterfowl, wading birds, mammals,

fish, reptiles, amphibians and other species 

that require shallow water for at least a part of 

their life cycle.

CONDITIONS WHERE PRACTICE APPLIES

On lands where water can be impounded or 

regulated by diking, excavating, ditching, 

and/or flooding.

On floodplain areas that provide refuge 

habitats for native fish during high flow periods. 

This practice does not apply to: 

• Wildlife Watering Facility (648) intended to 

provide watering places for wildlife; 

• Wetland Restoration (657) intended to 

rehabilitate a degraded wetland where the 

soils, hydrology, vegetation community, 

and biological habitat are returned to a 

close approximation of the original 

conditions; 

• Wetland Enhancement (659) intended for 

modification of an existing wetland where 

specific attributes are targeted by 

management objectives, possibly at the 

expense of other attributes, or the 

rehabilitation of a degraded wetland where 

the result is a wetland that is different than 

what previously existed on the site; 

• Wetland Construction (656) intended to 

treat point and non-point sources of water 

pollution; 

• Wetland Creation (658) for creating a 

wetland on a site which historically was not 

a wetland; or 

• Fish Pond Management (399).

CRITERIA

Soils must have low permeability or seasonal 

high water table to inhibit subsurface drainage 

and allow for maintenance of proper water 

levels.

Site must be free of hazardous materials.

Water supply for flooding the area during 

periods of planned inundation must be 

adequate. 

An adequate method for dewatering is required 

when water levels must be artificially lowered in 

order to produce desired habitat condition.

Water levels must be able to be maintained 

between 1 to 18 inches in depth over the 

majority of the area during periods of planned 

inundation. An exception to this criterion is 

made for floodplain habitats connected to 

stream channels where water depths of up to 6 

feet provide habitat for native fish species that 

use these habitats during periods of inundation 

associated with high stream flows. 

Where active habitat management is planned 

(such as disking or water level management) a 

point of access will be planned and developed 

to facilitate management activity.

Invasive plant species and federally/state listed 

noxious and nuisance species shall be 

controlled on the site.
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Existing drainage systems shall be utilized, 

removed or modified as needed to achieve the 

intended purpose.

Criteria for Waterfowl Habitat

Areas planned to provide waterfowl feeding 

and resting habitat shall be designed to 

facilitate gradual flooding of areas containing 

food plants to an average depth of 6 to 10 

inches.

Areas containing food plants shall be flooded 

during seasonal periods of waterfowl use.

Criteria for Shorebird Habitat

Areas planned to provide shorebird habitat 

shall have exposed mudflats and areas with 1 

to 4 inches of water during seasonal periods of 

shorebird use.

Criteria for Amphibian Habitat

Inundation shall be planned to last throughout 

the local breeding period of at least one

endemic amphibian species.

Surrounding upland habitat shall be of 

sufficient quality and quantity to support the 

complete life-cycle requirements of at least one 

endemic amphibian species.

Structures shall be designed to prevent fish 

access to areas planned for amphibian 

breeding habitat.

.

Criteria for Off-stream Stream Fish Habitat

Water control structures shall be designed to 

prevent native fish from being trapped as water 

recedes.

CONSIDERATIONS

Water volume, rates of runoff, infiltration, 

evaporation and transpiration will affect 

performance of the practice.

Nearly level sites will allow for larger units while 

keeping planned water depths within the 

optimum range over most of the unit.

Where impoundments are developed, 

shorelines with irregular shapes and varying 

side slopes from 9:1 to 20:1 along water 

surface margins may increase habitat diversity.

Consider how the timing of flooding and 

drawdown, as well as the type of drawdown, 

will affect moist soil plant species composition.

Consider tolerance of plants to flooding and 

salinity, as well as the composition of seed in 

the soil.

Nutrient and pesticide residues may affect 

plant species composition and the site’s 

capability to grow desirable plants.

Consider effects on nearby wetlands, or waterrelated fish and wildlife habitats.

Consider movement of dissolved and 

suspended substances to downstream surface 

waters and groundwater.

The practice may affect downstream flows, or 

aquifers that would affect other water uses or 

users.

Consider disease vectors such as mosquitoes.

The practice may function as a link in a habitat 

corridor that aids the site’s use and 

colonization by wetland flora and fauna.

The composition and extent of surrounding 

upland vegetation may influence this practice’s 

habitat functions.

Installation of vegetated buffers on surrounding 

uplands may improve water quality in the 

shallow water area.

The practice may raise downstream water 

temperature, causing detrimental impacts to 

associated aquatic and terrestrial communities.

Soil disturbance may increase the probability of 

invasion by unwanted plant species.

Added water depth and duration may be used 

as a method to control unwanted vegetation.

Biological control of undesirable plant species 

and pests (e.g., using predator or parasitic 

species) may be the least damaging alternative 

for pest control.

Human and livestock activities in and 

surrounding the practice may disturb wildlife, 

thereby decreasing habitat suitability and 

function. Vegetative screens, fences, or gates 

are means of reducing unwanted disturbance.

PLANS AND SPECIFICATIONS

Plans and specifications for installing 

structures for water control shall be in keeping 

with this standard and shall prescribe the 

requirements for applying the practice to 

achieve its intended purpose.
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Specifications shall be recorded using 

approved specifications sheets, job sheets, 

narrative documentation in the conservation 

plan or other acceptable documentation.

Specifications shall be reviewed and approved 

by a person with appropriate training in the 

design and implementation of shallow water 

areas to benefit fish and wildlife. 

OPERATION AND MAINTENANCE

The following actions shall be carried out to 

ensure that this practice functions as intended 

throughout its expected life. These actions 

include normal repetitive activities in the 

application and use of the practice (operation), 

and repair and upkeep of the practice 

(maintenance).

Waterfowl and shorebird feeding and resting 

areas that can be hydrologically controlled or 

have natural dry periods should be burned, 

disked or surface disturbed every 3-5 years to 

set back succession and control the growth of 

undesirable plants. Such burning, disking, or 

surface disturbance shall be scheduled to 

encourage desirable habitat plants.

Any use of fertilizers, mechanical treatments, 

prescribed burning, pesticides and other 

chemicals shall not compromise the capability 

of the practice to provide habitat for the target 

species.

Operation and maintenance shall include 

monitoring and management of structural 

components and habitat quality provided.

REFERENCES

Helmers, Doug. 1992. Shorebird Management 

Manual. Western Hemisphere Shorebird 

Reserve Network, Manomet, MA 58 pp.

Kingsbury, Bruce & Joanne Gibson, 2002. 

Habitat Management Guidelines for 

Amphibians and Reptiles of the Midwest. 

Partners in Amphibian & Reptile Conservation, 

Ft Wayne IN, 57 pp. 

Smith, Loren M. and Roger L. Pederson. 1989. 

Habitat management for migrating and 

wintering waterfowl in North America. Texas 

Tech University Press, 574 pp.