Dairy cows and milking facilities require a reliable high quality water supply. Dairy production is changing with larger production units being planned and constructed. These dairy facilities require a water supply that can deliver high quality water to the cows at all times in sufficient amounts to meet both physiological and sanitation needs of the facility.
The data reported in the literature for water consumption for dairy facilities varies considerably. For example, in three different studies the water needs for lactating cow consumption, and milking center cleaning range between 40 to 50 gallons fresh water per cow per day. In these studies the free stall units were flushed with recycled lagoon water in all areas except the milk parlor and milk room. This concept reduces the amount of water that is introduced into the waste management system.
Texas data illustrates that water use on eleven dairy farms varied widely, depending on the type of manure removal system and other factors. The greatest variable was the use of sprinkler cow wash systems and/or flush systems versus manual manure removal. The total amount of fresh water used for sanitation and manure removal averaged 39.6 gallons per cow per day. The mean value for each farm ranged from 12.3 to 69.2 gallons per cow per day. The water used for cattle drinking water troughs on seven of the dairies studied averaged 28.7±12.0 gallons per cow per day. Thus the Texas data average fresh water use per cow per day for sanitation and drinking was 68.3 gallons. Their data showed wide differences in water use for facilities that flushed or had cow sprinklers versus those that used manual cleanup. The average water use for milking parlors and holding pens without flush or cow sprinklers averaged 19.9±14.0 gallons per cow per day. In contrast, milking parlors and holding pens with sprinkler cow washers used an average of 47.1±17.7 gallons per cow per day.
Calculating Herd Requirements for Fresh Water
It is possible to estimate fresh water use on individual dairies, even with the wide variation reported in the literature. Estimates for total requirements can be developed for drinking water, wash pen sprinklers (if used), and milk house and parlor. Water needs can be estimated by completing Worksheet 1 (requires Adobe Acrobat) with information found in Tables 1-4.
Drinking Water Needs
Drinking water needs can be determined by using the information found in Table 1 and Table 2. Table 1 shows a typical herd makeup assuming a uniform year around calving, 13 month calving interval, a 33% replacement rate (1/2 supplying a calf), 50% female calves and males sold at birth for a 100 lactating cow herd.
|Category||Number||% of herd||Avg. weight (lbs.)|
|Total mature cows||100|
|16 - 24 months||42||38||1050|
|13 - 15 months||13||12||800|
|9 - 12 months||19||17||600|
|5 - 8 months||19||17||400|
|3 - 4 months||9||8||250|
|0 - 2 months||9||8||150|
Water intakes for dairy cattle are influenced by several factors including dry matter intake, milk production, ambient temperature, and sodium intake. However, Table 2 provides a good estimate of water intake based upon size, milk production and temperature. The data from the water intake table when matched with the herd makeup table will estimate herd drinking water.
|Weight (lb)||Milk (lb)||40° & below||60°||80°F|
|1 Maintenance and pregnancy|
|2 Maintenance and milk production|
Wash Pen Needs
The wash pen can be a large user of fresh water on typical dairies. The amount used is dependent on line pressure, sprinkler orifice, number of sprinklers and minutes per day used. Table 3 shows the gallons per minute per sprinkler with different line pressure in pounds per square inch. The number of sprinklers in the wash pen, the minutes used per day and the nozzle discharge will determine water used in the wash pen.
|1/8" dia.||9/64" dia.||5/32" dia.||11/64" dia.||3/16" dia.|
Milk House and Parlor Needs
Milk house and parlor waste can be estimated from data found in Table 4.
|Washing Operation||Water Volume|
|Automatic Wash||50 to 60 gal. per wash|
|Manual Wash||30 to 40 gal. per wash|
|Pipeline, in parlor
Volume is higher for long stanchion barns)
|75 to 125 gal. per wash|
|Pail Milkers||30 to 40 gal. per wash|
|Miscellaneous Equipment||30 gal. per day|
|Cow Prep Wash|
|Automatic||1 to 4.5 gal. per wash per cow|
|Manual||0.25 to 0.5 gal. per wash per cow|
|Parlor Floor||40 to 75 gal. per day|
|Milkhouse floor||10 to 20 gal. per day|
|Holding Pen (sprinklers)||5 gpm per head
(depending on nozzle size and pressure)
Dairies under construction or expanding must evaluate their water needs to ensure that a water source is capable of supplying the production needs of the facility. The information provided in this article can aid in that estimation.