The characteristics of the material to be managed will influence the selection of the specific handling components. The average herd size in Oregon is nearly 100 milking cows, so the total number of animals may be nearly double that. The manure production estimates shown Table 1 are for a herd of 191 animals, with 100 of them lactating cows. In addition to the manure produced on the dairy farm, several other wastes are commonly handled with the manure. These include bedding, soil, waste feed, and milkroom and parlor wastewater.
Quantities vary widely.
Influencing variation of waste water are type of cow preparation used, type and number of milking units, size of milking herd, buildings, use of a flushing collection system, season, and individual operator preference. Table 2 lists some of the values that can be used to estimate the additional waste volume that must be included in the waste management system. Review the existing facilities, noting their location, condition and size. Also, consider any planned expansion. Evaluate what components of the present waste handling system and equipment might be used in the expansion or new unit.