| ||Take home message | Water requirements | Types of water systems | Components of a feedlot water system | Waterer selection and location
This is a fact sheet from the Facilities and Environment section of the Alberta Feedlot Management Guide, Second Edition published September 2000. The 1200 page guide is available for purchase on CD-ROM.
Take Home Message
- A well designed feedlot watering system should provide an unrestricted, reliable supply of water to animals at all times of the year.
- A good feedlot water system needs:
- to be reliable with a backup pumping system;
- to require a minimum of maintenance;
- an adequate water supply from a sufficient number of watering units;
- a well designed piping system;
- the watering unit must provide a large enough surface area and depth to allow the animals to drink easily;
- the supply must be clean, fresh and free from contamination;
- the watering unit must be properly located and be able to withstand the rigours of an Alberta winter without freezing;
- the watering unit should be protected from the wind and livestock damage.
- Take care to properly design the entire water system.
Animals receive their daily water needs three ways. Through voluntary intake, through water content of the feed, and to a lesser extent from water formed within the body as a result of oxidation in the tissues. The voluntary intake of water by cattle is governed by:
Actual data concerning water intake in commercial Alberta feedlots is limited. Table 1, summarized from information developed by the Department of Animal Science, University of Nebraska, gives estimates of water intake of feedlot cattle at different weight and average air temperatures.
- animal size;
- animal breed;
- temperature of drinking water;
- air temperature, seasonal effects;
- salt content of feed and water;
- moisture content of the feed.
Table 1. Estimated Water Consumption of Cattle.
Conversion: 1 gallon = 4.5 litres
Water Intake (imperial gallons/head/day)
As a rule of thumb, a typical Alberta feedlot holding 600 to 1200 pound cattle will use about 8 gal per head per day but expect to use about 18 gal per head per day on peak demand days.
Some research has been done in Alberta on feedlot watering behaviour. Feedlot steers were tagged electronically. Their watering behaviour is shown in Figure 1. There are two peak periods of watering, one in the morning and the other in the afternoon, but generally the watering occurs over approximately a 12 hour period. If the watering system is designed to supply the entire water requirement over an 8 hour period the peaks will be accounted for.
Time spent at the waterer was also monitored. Healthy feedlot steers spent about 11½ minutes per day. Actual water consumption was not monitored, but assuming these animals were probably drinking 7 to 10 gallons per day, the water consumption rate at the waterer per animal was about 3/4 gallon per minute. This volume is seasonal and will vary from warmer to cooler parts of the province.
Types of Water Systems
Two basic types of watering systems are used in Alberta, conventional systems and constant flow systems.
These are basically standard pressure systems, with a pump and pressure tank supplying float valve controlled stock waterers. This system is shown in Figure 2.
The advantages of this system are low initial cost and operating only as needed. Disadvantages are mechanical valve problems and the need for water bowls to be heated or super-insulated in winter. Typically waterer heating costs are $30 - $130/year for a 100 head waterer.
A constant flow system uses a pumping system that runs 24 hours a day. The water flows through the waterers then overflows through a drain system. The drain system leads to an irrigation pond or is recirculated back to the waterers. It relies on the flowing water and heat from the earth to prevent freezing in winter. Figure 3 shows the system operation.
Advantages are the elimination of troublesome valves and no requirement for heating the waterers in winter. The cost of running the pump 24 hours per day will often be less than heating the waterers.
Disadvantages of recirculating systems are the high initial cost for the drainage system, the site must be appropriate for gravity drainage from all waterers, the pump must run 24 hours per day, and keeping the waterers and water clean.
It is strongly recommended that sick pens be on a separate watering system.
Components of a Feedlot Water System
When selecting a pump, the following factors need to be considered:
- gallons per minute required
- pressure needed to overcome piping friction loss, vertical lift above the pump and by waterer valves
- depth to water
- well casing size
- power supply voltage
- pump location
- pump durability and service
- dealer service
The cattle in a typical feedlot will consume most of their water over an 8 hour period, so the pumping system must be designed to supply this.
Example: pump size for 1000 head feedlot
1000 head feedlot X 10 gallons/head-day= 10,000 gallons/day. Delivered over 8 hours, 10,000 gallons/day divided by 480 minutes pumping time /day = 20 gallons per minute (gpm). The pump should deliver this water to the feedlot with at least 20 pounds per square inch pressure at the waterer. This is the minimum rate, if water is delivered over 4 hours, the rate will be 40 gpm.
In many feedlots more than one pump is used to accommodate a range in flow rates. A primary pump is used to provide basic water requirements. Secondary pumps kick in during peak watering periods. A multi- pump system is one way to provide this because it provides an automatic emergency back up. If one pump fails the other pumps can supply the cattle while repairs are being made. Smaller pumps cost less and are usually easier to repair or replace locally.
Continuous flow pumping systems require a similar design flow rate to conventional systems, but will not necessarily need to develop as high a pressure. A continuous flow system must have a backup pump plumbed into the system to accommodate repair or replacement of the main pump. Figure 4 shows a recommended configuration of pump, pumphouse and pressure tank.
Conventional pressure systems usually use a pressure tank and pressure switch to control the on-off cycles of the pump. In some larger feedlot systems a constant pressure controller is used to soft start the pump and vary the speed of the pump motor as demand changes. A similar result can be obtained by using a multi-pump system where a series of smaller pumps are staged to kick in as required.
The pressure tank must be sized to match the pump capacity. As a quick rule of thumb the pressure tank should have one gallon of draw-off capacity for every gallon per minute of pump capacity. Pump suppliers have selection charts for matching pumps and pressure tanks. A typical ‘bladder type’ pressure tank will have draw-off capacity of approximately one-third of its total volume so a 60 gallon tank will have a draw-off capacity of about 20 gallons between on-off cycles.
A standard pressure switch turns the pump on and off at preset pressure levels, typically on at 30 psi and off at 50 psi. More sophisticated pressure switches and controls are available. Some of these have features like overload protection and automatic reset to protect the pump.
Constant flow systems require very few controls. Pressure tanks and switches are not required because the pump runs continuously. The flow into individual waterers can be controlled by using different sizes of orifices or Dole flow
control valves that only allow a specific flow of water regardless of pressure.
Piping is an extremely important consideration in a feedlot water system. Pumps, tanks and other water system components are replaceable. Pipe, however, once buried will remain in use for a long time. Don’t skimp on the size of pipe or quality of pipe and fittings. No one has ever complained that they put in pipe that was too big. Therefore considerable thought should be used when selecting pipe size to accommodate the ultimate size of the feedlot. Although flow rates in a feedlot can vary significantly, pipe size should be chosen to accommodate maximum flow rates to insure proper water distribution. Don’t undersize the pipeline because of poor water source, upgraded water sources and intermediate storage systems can be brought into the design. Figure 5 gives pipe size requirement as a function of pipe length and required flow rate.
Figure 5. Pipe Size Requirements as a Function of Pipe Length and Flow Rate.
A typical layout will be comprised of main feeder lines that branch out into smaller branch lines to the individual waterers. For most Alberta feedlots these branch lines to individual waterers will be 1 inch or 1.25 inches inside diameter. Main feeder line sizes will depend on the flow required and may range from 1.25 inches to 4 inches ID. Coiled polyethylene pipe is usually used when pipe sizes 2 inches or less are required and rigid PVC is used for larger piping. The diagram shows recommended pipe sizes and capacities. Design the piping system to individually control the water supply to each waterer. This allows individual waterers to be shut down if a pen is empty or maintenance is required on a waterer. Design your system so the rest of the system does not need to be shut down. In smaller feedlots this can be accomplished by using individual supply lines from the pressure tank to each waterer. In a branching system ‘curb stop and drain or frost free hydrants’, that have valves located below frost level, can be used to shut off individual waterers.
Install separate lines to sick pens. This allows for in-line medication for sick pens only.
As a rule of thumb lines to individual waterers must supply at least 1 gallon per minute for each drinking spot at the waterer. If a waterer can accommodate six cattle drinking at one time the supply line should be able to provide 6 to 10 gallons per minute. The relative elevations of waterers can be a factor in design and layout. For example if one waterer is on top of a hill and a second waterer is at the base of the hill, the waterer at the base will require less pressure to operate and will be in a priority situation as far as water supply is concerned. If the water supply is not adequate or the piping is underdesigned the bottom waterer will get all the water and the top one will get none.
Considerations for selecting the kind of pipe:
Waterer Selection and Location
- probable life expectancy;
- resistance to corrosion;
- resistance to deposits forming inside the pipe;
- safe working pressure;
- resistance to puncture;
- lengths available;
- ease of bending;
- comparative cost;
- ease of installation;
- type of pipe connection required.
Livestock waterers may be located in a number of areas in the pen. Regardless of the location, the waterer should be placed on a concrete pad in a well drained area. It should be easily accessible to all animals, and preferably some distance from the feed bunk to prevent animals from depositing feed in the waterer. The concrete pad should extend 7 to 10 feet out from the base of the waterer.
Most new feedlot developments include one waterer per pen rather than one waterer in the fence line between two pens. The usual location is the midpoint of the feedbunk and 20' to 40' back from the bunk. Locate the waterer near the top or drier part of the pen. Install a pipe frame over the waterer to protect it from physical damage or cattle entry.
The argument for the fence line waterers was that two waterers per pen gave an extra cattle access point for less dominant cattle. There is also a risk of disease transmission with waterers shared between pens.
Longer, narrow troughs are usually selected for feedlot use, providing for an optimum of water trough space per head. As a rule a waterer should have a minimum of 1.2 inches of waterer space per head. (‘Canadian Cattlemen - Quality Starts Here’) Most manufacturers rate their waterers by animal capacity.
Considerations for selecting an ideal waterer. It should be:
Electrically heated waterers
- easily cleaned;
- not be easily fouled;
- require little or no operation by the animal, that would cause a drop in intake;
- be of adequate size for the size and number of animals;
- able to provide an adequate water supply at all times;
- designed using a minimum of working parts;
- able to allow the animal to drink easily;
- easy to service in winter. (When ice builds up around the waterer it is often easier to service a waterer with top access than one with a small access door on the side.);
- as energy efficient as possible.
Most waterers used in feedlots utilize electricity to prevent freezing. It is important to insure these waterers are securely anchored to the concrete, and adequately grounded. Proper installation of the riser pipe from the water supply line to the waterer itself is also critical.
Heavy duty concrete waterers are popular in Southern Alberta feedlots. They are rugged and well insulated. They are set on the concrete pad with caulking on the base to prevent air leakage. Some installers use a jig to put an indentation in the concrete pad, to match the base of the waterers. This prevents shifting of the water on the base, yet it can still be lifted off the base if it needs to replaced. To prevent ice buildup around concrete waterers, spillage caused by the cattle must be prevented. This is done by choosing a deep bowl waterer and by setting the float to maintain a lower water level in the winter.
PAMI Tests during 1990 indicated that the annual electricity cost for operating a typical 100 head waterer would range from $30 to $130 per year (assuming 7 ¢ per kilowatt hour). Waterer size, insulation thickness, water temperature, thermostat setting, weather stripping, and water surface area all have an effect on heating costs.
Energy efficient waterers have extra thick insulation in the base and thermal covers to prevent heat loss. Figure 6 shows waterer installation with individual water shut off and proper electrical grounding.
Energy free waterers
Energy free waterers are also being used, but require additional management. These waterers are super insulated and use movable covers to keep the water from freezing. They work well if they get lots of use every day and are checked first thing in the morning and last thing at night. Note the time of minimum water use in the watering pattern diagram. The covers can freeze shut over night or icicles can hold the covers open, allowing the heat from the water to escape. They must be installed properly, according to the manufacturer’s instructions.
The shortcomings of energy free waterers are that the animals must learn to operate the covers and if the waterer does freeze badly it can be very difficult to thaw. Minor freezing problems can usually be thawed by a kettle of hot water. The ice that forms during cold weather must be chipped away and removed daily. New animals sometimes have a difficult time learning to drink from the waterers. Figure 7 shows how to install this type of waterer.
Some producers have been installing heating tapes with energy free waterers as an added safety measure.
Water is the most essential nutrient in the life of a feedlot animal. A feedlot water system should be well thought out,
well designed to ensure its capability of delivering an acceptable quantity of water to each watering unit in the feedlot. Animals must have unrestricted access to the watering unit. A good design will require a minimum amount of the operators time to maintain the system, and ensure adequate trouble free water delivery for a number of years.
Figure 1. Watering Pattern and Space Requirements.
Figure 2. Water System Layout for 1000 Head Feedlot.
Figure 3. Constant Water Flow System.
Figure 4. Pumphouse and Pressure Tank.
Figure 6. Automatic Livestock Waterer.
Figure 7. Energy Free Waterer.
Orin Kenzie, Alberta Agriculture, Food and Rural Development, and Ken Williamson, Alberta Agriculture, Food and Rural Development, 2000. Alberta Feedlot Management Guide.