3f1 feedlot water system - agromedia

Alberta Feedlot Management Guide 3F1:1

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Feedlot Water System

Orin Kenzie and Ken Williamson

Take Home Message

✓ A well designed feedlot watering system should provide anunrestricted, reliable supply of water to animals at all times ofthe 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.

Water Requirements

Animals receive their daily water needs three ways. Throughvoluntary intake, through water content of the feed, and to alesser extent from water formed within the body as a result ofoxidation in the tissues. The voluntary intake of water by cattleis governed by:• animal size;• animal breed;• temperature of drinking water;• air temperature, seasonal effects;• humidity;• wind;• salt content of feed and water;• moisture content of the feed.

Actual data concerning water intake in commercial Albertafeedlots is limited. Table 1, summarized from informationdeveloped by the Department of Animal Science, University ofNebraska, gives estimates of water intake of feedlot cattle atdifferent weight and average air temperatures.


As a rule of thumb, a typical AlbertaFeedlot holding 600 to 1200 poundcattle will use about 8 gal per headper day; but expect to use about 18gal per head per day on peak demanddays.

Some research has been done inAlberta on feedlot wateringbehaviour. Feedlot steers weretagged electronically. Their wateringbehaviour is shown in Figure 1. Thereare two peak periods of watering, one

in the morning and the other in the afternoon, but generallythe watering occurs over approximately a 12 hour period. Ifthe watering system is designed to supply the entire waterrequirement over an 8 hour period the peaks will beaccounted for.

Time spent at the waterer was also monitored. Healthy feedlotsteers spent about 11½ minutes per day. Actual waterconsumption was not monitored, but assuming these animalswere probably drinking 7 to 10 gallons per day, the waterconsumption rate at the waterer per animal was about 3/4gallon per minute. This volume is seasonal and will vary fromwarmer 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.

Conventional systems

These are basically standard pressure systems, with a pumpand pressure tank supplying float valve controlled stockwaterers. This system is shown in Figure 2.

The advantages of this system are low initial cost andoperating only as needed. Disadvantages are mechanicalvalve problems and the need for water bowls to be heated orsuper-insulated in winter. Typically waterer heating costs are$30 - $130/year for a 100 head waterer.

Constant flow

A constant flow system uses a pumping system that runs 24hours a day. The water flows through the waterers thenoverflows through a drain system. The drain system leads to anirrigation pond or is recirculated back to the waterers. It relieson the flowing water and heat from the earth to preventfreezing in winter. Figure 3 shows the system operation.

Table 1. Estimated Water Consumption of Cattle.

Animal WeightAverage 600 lb 800 lb 1000 lb 1200 lbTemp Water Intake (imperial gallons/head/day)

2°C 4.4 5.6 6.8 7.610°C 5.2 6.4 7.6 8.420°C 6.8 8.0 9.6 1125°C 7.6 9.6 11 1330°C 11 14 16 18

conversion: 1 gallon = 4.5 litres


Advantages are the elimination of troublesome valves and norequirement for heating the waterers in winter. The cost ofrunning the pump 24 hours per day will often be less thanheating the waterers.

Disadvantages of recirculating systems are the high initial costfor the drainage system, the site must be appropriate forgravity drainage from all waterers, the pump must run 24 hoursper day, and keeping the waterers and water clean.

It is strongly recommended that sick pens be on a separatewatering system.

Components of a Feedlot Water System

Pump selection

When selecting a pump, the following factors need to beconsidered:• 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

Pump capacity

The cattle in a typical feedlot will consume most of their waterover an 8 hour period, so the pumping system must bedesigned 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 480minutes pumping time /day = 20 gallons per minute (gpm).The pump should deliver this water to the feedlot with at least20 pounds per square inch pressure at the waterer. This is theminimum rate, if water is delivered over 4 hours, the rate will be40 gpm.

In many feedlots more than one pump is used to accommodatea range in flow rates. A primary pump is used to provide basicwater requirements. Secondary pumps kick in during peakwatering periods. A multi- pump system is one way to provide


this because it provides an automatic emergency back up. Ifone pump fails the other pumps can supply the cattle whilerepairs are being made. Smaller pumps cost less and areusually easier to repair or replace locally.

Continuous flow pumping systems require a similar designflow rate to conventional systems, but will not necessarilyneed to develop as high a pressure. A continuous flow systemmust have a backup pump plumbed into the system toaccommodate repair or replacement of the main pump. Figure4 shows a recommended configuration of pump, pumphouseand pressure tank.

Pump controls

Conventional pressure systems usually use a pressure tank andpressure switch to control the on-off cycles of the pump. Insome larger feedlot systems a constant pressure controller isused to soft start the pump and vary the speed of the pumpmotor as demand changes. A similar result can be obtained byusing a multi-pump system where a series of smaller pumpsare 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 onegallon of draw-off capacity for every gallon per minute ofpump capacity. Pump suppliers have selection charts formatching pumps and pressure tanks. A typical ‘bladder type’pressure tank will have draw-off capacity of approximatelyone-third of its total volume so a 60 gallon tank will have adraw-off capacity of about 20 gallons between on-off cycles.

A standard pressure switch turns the pump on and off at presetpressure levels, typically on at 30 psi and off at 50 psi. Moresophisticated pressure switches and controls are available.Some of these have features like overload protection andautomatic reset to protect the pump.

Constant flow systems require very few controls. Pressuretanks and switches are not required because the pump runscontinuously. The flow into individual waterers can becontrolled by using different sizes of orifices or Dole flowcontrol valves that only allow a specific flow of waterregardless of pressure.

Piping

Piping is an extremely important consideration in a feedlotwater system. Pumps, tanks and other water systemcomponents are replaceable. Pipe, however, once buried willremain in use for a long time. Don’t skimp on the size of pipeor quality of pipe and fittings. No one has ever complained


that they put in pipe that was toobig. Therefore considerablethought should be used whenselecting pipe size toaccommodate the ultimate sizeof the feedlot. Although flowrates in a feedlot can varysignificantly, pipe size should bechosen to accommodatemaximum flow rates to insureproper water distribution. Don’tundersize the pipeline because ofa poor water source, upgradedwater sources and intermediatestorage systems can be broughtinto the design. Figure 5 givespipe size requirement as afunction of pipe length andrequired flow rate.

A typical layout will be comprisedof main feeder lines that branch

out into smaller branch lines to the individual waterers. Formost Alberta feedlots these branch lines to individual watererswill be 1 inch or 1.25 inches inside diameter. Main feeder linesizes will depend on the flow required and may range from1.25 inches to 4 inches ID. Coiled polyethylene pipe is usuallyused when pipe sizes 2 inches or less are required and rigidPVC is used for larger piping. The diagram showsrecommended pipe sizes and capacities. Design the pipingsystem to individually control the water supply to eachwaterer. This allows individual waterers to be shut down if apen is empty or maintenance is required on a waterer. Designyour system so the rest of the system does not need to be shutdown. In smaller feedlots this can be accomplished by usingindividual supply lines from the pressure tank to each waterer.In a branching system ‘curb stop and drain or frost freehydrants’, that have valves located below frost level, can beused to shut off individual waterers.

Install separate lines to sick pens. This allows for in-linemedication for sick pens only.

As a rule of thumb lines to individual waterers must supply atleast 1 gallon per minute for each drinking spot at the waterer.If a waterer can accommodate six cattle drinking at one timethe supply line should be able to provide 6 to 10 gallons perminute.

Figure 5. Pipe Size Requirements as a Function of PipeLength and Flow Rate.


The relative elevations of waterers can be a factor in designand layout. For example if one waterer is on top of a hill and asecond waterer is at the base of the hill, the waterer at the basewill require less pressure to operate and will be in a prioritysituation as far as water supply is concerned. If the watersupply is not adequate or the piping is underdesigned thebottom waterer will get all the water and the top one will getnone.

Considerations for selecting the kind of pipe:• 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.

Waterer Selection and Location

Location

Livestock waterers may be located in a number of areas in thepen. Regardless of the location, the waterer should be placedon a concrete pad in a well drained area. It should be easilyaccessible to all animals, and preferably some distance fromthe feed bunk to prevent animals from depositing feed in thewaterer. The concrete pad should extend 7 to 10 feet out fromthe base of the waterer.

Most new feedlot developments include one waterer per penrather than one waterer in the fence line between two pens.The usual location is the midpoint of the feedbunk and 20' to40' back from the bunk. Locate the waterer near the top ordrier part of the pen. Install a pipe frame over the waterer toprotect it from physical damage or cattle entry.

The argument for the fence line waterers was that twowaterers per pen gave an extra cattle access point for lessdominant cattle. There is also a risk of disease transmissionwith waterers shared between pens.

Longer, narrow troughs are usually selected for feedlot use,providing for an optimum of water trough space per head. Asa rule a waterer should have a minimum of 1.2 inches ofwaterer space per head. (‘Canadian Cattlemen - Quality StartsHere’) Most manufacturers rate their waterers by animalcapacity.


Waterer Selection

Considerations for selecting an ideal waterer. It should be:• 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 accessthan one with a small access door on the side.);

• as energy efficient as possible.

Electrically Heated Waterers

Most waterers used in feedlots utilize electricity to preventfreezing. It is important to insure these waterers are securelyanchored to the concrete, and adequately grounded. Properinstallation of the riser pipe from the water supply line to thewaterer itself is also critical.

Heavy duty concrete waterers are popular in Southern Albertafeedlots. They are rugged and well insulated. They are set onthe concrete pad with caulking on the base to prevent airleakage. Some installers use a jig to put an indentation in theconcrete pad, to match the base of the waterers. This preventsshifting of the water on the base, yet it can still be lifted off thebase if it needs to replaced. To prevent ice buildup aroundconcrete waterers, spillage caused by the cattle must beprevented. This is done by choosing a deep bowl waterer andby setting the float to maintain a lower water level in thewinter.

PAMI Tests during 1990 indicated that the annual electricitycost for operating a typical 100 head waterer would rangefrom $30 to $130 per year (assuming 7 ¢ per kilowatt hour).Waterer size, insulation thickness, water temperature,thermostat setting, weather stripping, and water surface areaall have an effect on heating costs.

Energy efficient waterers have extra thick insulation in thebase and thermal covers to prevent heat loss. Figure 6 showswaterer installation with individual water shut off and properelectrical grounding.


Energy Free Waterers

Energy free waterers are also being used, but requireadditional management. These waterers are super insulatedand use movable covers to keep the water from freezing. Theywork well if they get lots of use every day and are checked firstthing in the morning and last thing at night. Note the time ofminimum water use in the watering pattern diagram. Thecovers can freeze shut over night or icicles can hold the coversopen, allowing the heat from the water to escape. They mustbe installed properly, according to the manufacturer’sinstructions.

The shortcomings of energy free waterers are that the animalsmust learn to operate the covers and if the waterer does freezebadly it can be very difficult to thaw. Minor freezing problemscan usually be thawed by a kettle of hot water. The ice thatforms during cold weather must be chipped away andremoved daily. New animals sometimes have a difficult timelearning to drink from the waterers. Figure 7 shows how toinstall this type of waterer.

Some producers have been installing heating tapes withenergy free waterers as an added safety measure.

Water is the most essential nutrient in the life of a feedlotanimal. A feedlot water system should be well thought out,well designed to ensure its capability of delivering anacceptable quantity of water to each watering unit in thefeedlot. Animals must have unrestricted access to the wateringunit. A good design will require a minimum amount of theoperators time to maintain the system, and ensure adequatetrouble 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 Flow Watering System.


Figure 4. Pumphouse and Pressure Tank.


Figure 6. Automatic Livestock Waterer.


Figure 7. Energy Free Waterer.

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