GRAZING 

A Guide to Reducing  Water Quality Impacts  Potential Water Quality Problems Critical Areas and Issues Assessing Existing Conditions Making Improvements     Funding and Technical Assistance

POTENTIAL WATER QUALITY PROBLEMS

Grazing, if not carefully managed, can cause water quality problems by increasing sediment, nutrients and bacteria levels. While sediment, nutrients and bacteria all occur naturally in water, livestock in some situations can increase concentrations of these substances beyond what is allowed by state and national water quality standards.   

Increased sediment concentrations can impact fisheries and other aquatic life. This may include less successful spawning activity, a change in the macro-invertebrate population, and a change in the aquatic plant community.  In addition, overgrazing can increase water temperature if riparian plant species that normally provide shade are eliminated.

Increased nutrient concentrations can cause over fertilization of waterbodies creating a condition known as eutrophication.  This situation, which is often more serious in lakes than streams, results in excessive algal growth.  When the algae die and decompose, oxygen is depleted.  Depending on the extent of the oxygen depletion, a fish kill may result.  Increased nutrient levels can also impact water supplies that are used for human consumption. Elevated nitrate levels can interfere with the blood's ability to carry oxygen.  This can be a serious problem for infants and the elderly.  

Increased bacteria counts can impact water supplies that are used for human consumption or for activities such as swimming.  Bacteria may cause a number of human diseases depending the type of bacteria.  

CRITICAL AREAS AND ISSUES

Healthy rangelands are a common goal of livestock production and water quality protection.  The challenge is to manage grazing so that rangelands thrive and water quality is protected.

While all rangeland is important, it is especially important that riparian areas be carefully managed.  Animals often concentrate in these areas because they provide a source of drinking water and produce lush vegetation.  Since they are near water, overgrazing riparian areas has the potential to create more water quality problems than overgrazing upland areas. 

Livestock producers should view riparian areas like a sponge.  As long as they are not overgrazed, they will continue to soak up moisture from the surrounding water source and produce abundant vegetation. Under these conditions riparian areas produce abundant forage and protect water quality.   When overgrazed, the ability of riparian areas to soak up moisture is greatly diminished.  Soils become compacted and forage is reduced resulting in less water quality protection. (An excellent video on this subject, entitled 'The Value of Riparian Areas', is available from the Wyoming Department of Agriculture 307/777-7323.)

Because of their importance, riparian areas should be carefully addressed in a grazing management system. The producer should be flexible and willing to change methods when conditions dictate.  Whether managing upland or riparian areas, things to consider are: range type and condition; range site potential and soil type; plant growth rates; precipitation; and type and class of livestock.  These factors will determine optimal stocking rates and rotation patterns. 

To improve range condition and protect water quality, a number of management tools are outlined in the 'Making Improvements' section of this web site.  However, before improvements are planned existing conditions should be assessed.

ASSESSING EXISTING CONDITIONS

An excellent source of information for assessing the condition of rangeland is the 'National Range and Pasture Handbook' published by the Natural Resources Conservation Service. This document outlines procedures for: calculating production of forage species; determining which species are being utilized; and evaluating overall range health. 

The technical aspects of the National Range and Pasture Handbook should be combined with human observation of existing conditions.  For example, proximity to a surface water body is a key consideration.  There is a  potential  for a water quality impact if any of the following exist:

• A surface waterbody is located within, or near, the grazing unit.

• Runoff from the grazing unit flows toward a waterbody.

• The ground water table is shallow (or comes in contact with the surface) in areas where livestock congregate.

If any of these conditions exist, further assessment is important.  In these situations, a water quality impact is likely if any of the following apply:

• The unit is heavily grazed (based on scientific analysis, visual comparison to excluded areas, examination of historic photos, etc.)

• There are few, if any, livestock watering sources other than natural waterbodies.

• Livestock remain in a single grazing unit for a long period of time. 

• There is little attempt to distribute grazing intensity through practices such as salting, dispersed watering, herding, land treatment, etc.

Grazing systems should be designed to address these situations and thereby reduce water quality impacts.  Generally, management practices that allow for seasonal rotation of livestock between grazing units, and distribute grazing pressure throughout those units, tend to reduce water quality impacts.

MAKING IMPROVEMENTS

A number of Best Management Practices (BMPs) have been used by livestock producers and land managers to improve grazing capacity and protect water quality.  These include:

• Fencing (to create multiple grazing units and allow rotation)

• Water development (to distribute grazing pressure & reduce pressure on natural water sources)

• Salting (to distribute grazing pressure)

• Herding (to distribute grazing pressure)

• Access roads (to allow access for management)

• Windbreaks (to protect and distribute livestock)

• Land treatment such as burning, spraying, seeding (to increase forage production and distribute grazing pressure)

• Water gaps (fencing to allow access to a portion of a waterbody while excluding livestock from the remainder of the riparian area)

• In-stream modifications such as rip-rap, check dams, drop structures, etc.

• Tree planting in riparian areas

• Beaver management to enhance riparian areas (may include re-introduction or population control depending on situation) 

Details of how, when and where to apply these practices in order to achieve the best results are available from the following sources:

• DEQ's 'Grazing Best Management Practices' (requires Adobe Acrobat Reader)

• EPA's Grazing BMPs

• EPA's Riparian BMPs

FUNDING AND TECHNICAL ASSISTANCE

Section 319 funds are available to assist with the improvement of grazing systems on private rangeland.  Applicants for these funds must show that a water quality problem exists and that the proposed practices will improve the problem. Interested parties should apply through their local conservation district.  The NRCS may have funds available through the Environmental Quality Incentives Program. The Wyoming Game and Fish Department has funds for practices that benefit fisheries.

Technical assistance is available from local conservation districts and from the Natural Resources Conservation Services.  BLM and Forest Service personnel can provide technical assistance (and sometimes financial assistance) for practices on federal land. Other sources of information, on the Internet, include:

• Natural Resources Conservation Service
• Grazing Lands Technology Institute
• Environmental Protection Agency (agricultural information)
• Purdue University Agricultural Publications
• USGS's Riparian Area Literature Summary 

• Watershed Management Council Newsletter

• Colorado State University Publications

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