Livestock Water Requirement
Gallons per head per day and total herd demand by temperature interpolation between user-supplied breakpoints.
Example
You enter
- Method table
- Head count 50
- Air temperature (°F) 80
- Low breakpoint temp (°F) 40
- Gallons/head at low temp 8
- High breakpoint temp (°F) 90
- Gallons/head at high temp 20
- Lactating false
You get
- Gallons per head per day 17.6 gal/head/day
- Total herd gallons per day 880 gal/day
Checked against published worked examples from: NRC / USDA NRCS water-intake guidance (user-supplied breakpoints).
Details, formula, and sources
ScopeGallons per head per day and total herd demand by temperature interpolation between user-supplied breakpoints, or the dry-matter-intake ratio method, with a lactation doubling.
Formula or tableTable: per-head gallons interpolated linearly between two user-supplied temperature breakpoints. Intake ratio: gallons = DMI * water_per_DMI / 8.345. Lactation roughly doubles demand.
Source and editionPer NRC Nutrient Requirements of Beef Cattle / Dairy Cattle water-intake guidance and the USDA NRCS National Range and Pasture Handbook water section, by name; breakpoints user-supplied.
Free accessFree NRCS guidance at nrcs.usda.gov; per-class gallon breakpoints are table values, not reproduced.
What governsEstimate. AHJ and licensed professional govern.
API field namesmethod, head, temp_f, t_low_f, gal_low, t_high_f, gal_high, lactating, per_head_gpd, herd_gpd
- Breakpoints per-class temperature/gallon breakpoints user-supplied from NRC / NRCS tablesNRC / NRCS