By Steve Glasgow
Livestock watering system designs are based on needed storage, delivery rates, and spacing requirements for the anticipated herd size for the grazing unit, the projected carrying capacity (based on a grazing plan and forage inventory), and/or the highest anticipated demand.
NRCS provides technical assistance in the planning and installation of watering systems and facilities for livestock. Assistance may include size of tanks, pump requirements, pipelines and aprons to hold facilities. The following provides an overview of the design criteria used by NRCS field offices.
Watering facility defined
"Water storage facilities" are tanks that hold water and serve other facilities via pipelines. These are usually taller structures and no animals drink from them. They are designed to provide enough storage to store the drinking water required by the design.
"Combination drinking and storage facilities" are tanks with a wall height such that animals drink from it, however, it is large enough to store the drinking water required by the design.
"Drinking facilities" are small troughs or tanks that have no significant storage and provide drinking space for a limited number of animals. These facilities are dependent on quick recharge. Flow rates must be adequate to supply 2.0 GPM / drinking hHead for large livestock. Flow rates for small livestock such as sheep, pigs and goats are to be based on 0.5 GPM / drinking head. The number of drinking head is limited by the drinking space around the facility. The system is designed to water all the livestock in the grazing unit within two hours. Freeze-proof tanks and energy-free fountains are also considered to be drinking facilities. When an energy free fountain is used, it shall be the primary source of water for the pasture in order to make the fountain function without freezing.
"Drinking facilities" installed where a system malfunction or interruption in service is immediately evident, such as house wells or pipelines tied to livestock feeding operations, are not required to meet the two days of storage, however a minimum tank capacity of 100 gallons must be provided. This 100-gallon storage requirement is waived for freeze-proof tanks and energy-free fountains.
Portable facilities are "drinking facilities" which can be moved to different locations. Portable facilities are limited in their ability to provide storage and remain portable, therefore only being used in areas where other dependable water supplies are available for emergency use. These facilities work best in situations for distributing grazing, intensive rotational systems and offsite water to minimize use of ponds and streams without the use of fence to exclude access.
Common materials include reinforced concrete, steel, and fiberglass. Pre-cast, freeze-proof concrete tanks and factory fabricated fiberglass tanks may be used. All designs meet the industry standards for the material being used. Tanks may also be constructed from heavy equipment tires. Used steel tanks, such as those used for oil or gasoline, can be used if the supplier certifies the tank's use for livestock.
Site selection should ensure the facility does not cause an adverse impact on the land. They may be located in under-utilized portions of a grazing unit to reduce grazing pressure on sensitive areas. Watering facilities may be located to facilitate and control stock movement and are generally located near the middle of a pasture.
Slope, barriers, pasture design and travel distance are included in the design and layout to address grazing distribution. Spacing requirements within a grazing unit are based on the following guidelines:
- Other dependable drinking facilities within the grazing unit,
- The need for water in a given location (example would be to distribute grazing)
- Terrain, as described in the accompanying table. This table shows the optimum water spacing within a grazing unit. Closer spacing could result in more uniform utilization of forages. Water supplies outside the spacing ranges shown are planned to meet 100% of herd demand. However, to improve grazing distribution within the spacing ranges (i.e. ½ mile for rolling terrain), water needs are adjusted to not less than 60% of needs.
A complete watering system includes both the storage part and the drinking part of the facility. Storage and drinking facilities can be provided in combination or they can be provided separately by connecting the components with pipelines to meet the livestock and/or wildlife demand.
Consumption needs are based on the guidelines found in the table below.
The water system is designed to provide a total system capacity for a five-day storage if the supply is dependent upon a windmill or solar system. A minimum of two-day storage is planned for systems powered by electricity, by rural water districts or other public water systems.
Drinking space and size
For "combination drinking and storage facilities", size requirements are governed by the water demand for the herd and not by drinking space. For "drinking facilities" the perimeter of the facility shall be a minimum of one inch per head in the herd. This requirement is waived for freeze-proof tanks and energy-free fountains.
The table on drinking space (below) per head is to be used as a guide. Divide the facility perimeter by the drinking space/head. Facility height may vary from 22 to 36 inches for horses, beef, and dairy cattle. For sheep and goats, the facility height may vary from 8 to 22 inches.
NRCS also provides guidance for operation and maintenance of facilities, including:
- check for debris, algae, sludge or other materials in the facility which may restrict the inflow or outflow system
- check for leaks and repair if any leaks are found
- check the automatic water level device to ensure proper operation
- check to ensure that adjacent areas are well protected against erosion
- check to ensure the outlet pipe is freely operating and not causing erosion problems
- prepare guidance for winter weather
- such as adding material in the storage area to allow for ice expansion without damage
- and have a schedule for periodic cleaning of the facility
Pipelines serving a watering facility are planned to meet the requirements of the watering facility. The type of facility served by the pipeline will influence the pipeline requirements. The flow rate to a water storage facility is governed by the water source and recharge rate. The recharge rate must be twice the seasonal high daily use in a 24-hour period.
Due to the variable flow rates from solar pumps, pipelines serving water storage facilities from solar powered units must be sized based on the peak flow of the selected solar pump that is required to meet the water needs. The minimum pipe size, inside diameter, allowed is 3/4-inch. All pipes must meet the industry standards for the material being used. Approved pipe material include steel, polyvinyl chloride, and polyethylene.
NRCS also provides guidance for operation and maintenance of pipelines that includes:
- opening/closing of valves to prevent excessive water hammer
- filling at the specified rate requirements
- inspecting and testing valves, pressure regulators, pumps, switches and other appurtenances
- maintaining erosion protection at outlets
- checking for debris, minerals, algae and other materials which may restrict the system flow
- draining and/or providing for cold weather operations system.
Pumps that convey livestock water are designed to meet the flow-rate requirements of the watering facility, based on hydraulic head, efficiency, and available horsepower. NRCS provides design assistance on pumps powered by electricity, internal combustion engine, solar, and wind. Power units are selected based on availability of fuel, power cost, operating conditions, conservation needs, and the objectives of the landowner.
NRCS also provides guidance for operation and maintenance of pumping plants that includes:
- inspection or testing of all pumping plant components and appurtenances
- proper start up procedures for the operation of the pumping plant
- routine maintenance of all mechanical components (power unit, pump, drive train, etc.) in accordance with the manufacturer's recommendations
- procedures to protect the system from freezing
- periodic checks and removal of debris as necessary from trash racks and structures to assure adequate flow capacity reaches the pumping plant
- periodic inspection of all safety features to ensure they are in place and functional.
Programs administered through NRCS, such as EQIP, are available and can provide payments for the installation of water facilities. To learn more about these programs visit your local NRCS office.
Glasgow is the state range conservationist for Oklahoma.