How much water cattle drink in a day, and what that takes off the tank
On a summer day that reaches 90°F, a beef cow nursing a calf needs about 2 gallons of water for every 100 pounds she weighs, and a 1,000-pound steer about 21 gallons. The same steer needs about 13 gallons at 70°F, so the tank that waters a herd falls far faster in August than in spring.
By Luke Patterson, co-founder of Trivertix. Last checked October 13, 2026.
Daily water intake by class and temperature
The table is the National Research Council's, as Mississippi State University Extension prints it: gallons a head a day, at the day's air temperature. Intake, as extension services use the word, usually counts the water in feed as well as what is drunk, so cattle on green grass drink less than the figure and cattle on dry hay nearer it.
| 70°F | 80°F | 90°F | |
|---|---|---|---|
| Growing calf, 400 lb | 5.8 | 6.7 | 9.5 |
| Growing calf, 600 lb | 7.8 | 8.9 | 12.7 |
| Finishing steer, 1,000 lb | 12.6 | 14.5 | 20.6 |
| Nursing cow, 900 lb | 16.9 | 17.9 | 16.2 |
| Mature bull, 1,400 lb | 11.7 | 13.4 | 19.0 |
Two things in the table are worth knowing. From 70°F to 90°F every class but the nursing cow needs 62 to 64 percent more water. And the table gives a nursing cow less at 90°F than at 80°F, 16.2 gallons against 17.9. The Nebraska rule below puts a 900-pound nursing cow at 18 gallons on a 90°F day, so plan from the larger figure.
Sources, read October 13, 2026: Mississippi State University Extension, Publication 2490: Beef Cattle Water Requirements and Source Management (PDF), University of Nebraska–Lincoln Beef: Water Requirements for Beef Cattle.
Rules of thumb for a hot day
The table stops at 90°F, and South Texas summers do not. These figures from extension services are quicker to work in your head, and one comes from a Texas heat wave.
- By weight
- On a day that reaches 90°F, a growing animal or a nursing cow needs about 2 gallons for every 100 pounds of body weight, and a dry cow or a bull about 1.
- A cow and her calf
- A spring-calving cow needs 20 to 24 gallons a day for herself in hot weather, and her calf another 5 to 10: 25 to 34 gallons for the pair.
- In a Texas heat wave
- With temperatures over 100 across the state in July 2022, Texas A&M AgriLife put a 1,000-pound heifer at about 20 gallons a day.
Shade in summer cuts how much cattle drink. Cool water does the opposite, and that is to the good: cattle drink and eat more when the water is cool, and a trough in the sun warms through the afternoon. Brahman-influenced cattle drank less than Herefords in the studies Mississippi State cites, so a herd with Brahman blood may sit at the low end of each range.
Sources, read October 13, 2026: University of Nebraska–Lincoln Beef: Water Requirements for Beef Cattle, Texas A&M AgriLife Today: Keep cattle hydrated and healthy, Mississippi State University Extension, Publication 2490: Beef Cattle Water Requirements and Source Management (PDF).
From the herd to the tank
Where a storage tank feeds the trough through a float valve, the trough holds its level and the storage tank does the falling. So the herd's day shows up on the storage tank, in inches.
- The herd
- 30 cow-calf pairs at 25 to 34 gallons a pair
- A hot day's water
- 750 to 1,020 gallons
- Off a tank 8 feet across
- 23.9 to 32.6 inches a day, at 31.3 gallons an inch
Work it for your own herd: add up the head of each class from the table, at the hottest temperature you expect, and divide by the gallons an inch of your tank holds. For an upright round tank, the guide to reading a gauge gives the gallons an inch for each width.
Then set the low alert line at least a day's water above the outlet, which on this tank is about 33 inches. That leaves time to find a stuck float, a tripped pump or a split line before the trough runs dry. Watch a week of readings in the heat and move the line once you know how fast your tank really falls.
Source, read October 13, 2026: University of Nebraska–Lincoln Beef: Water Requirements for Beef Cattle.
Source, read October 7, 2026: NIST Handbook 44 (2026), Appendix C (PDF).
Where a level monitor fits
A monitor reads the tank for you and tells you when the level crosses your line. Trivertix is one: an ultrasonic sensor at the top of the tank reads down to the water about every 15 minutes, and sends the reading by LoRa radio to a receiver in the house. In the app you set one high and one low alert line, each with its own switch.
The first pilot units went onto cattle watering tanks on the Patterson ranch outside Karnes City, Texas, and have come through Karnes County summers there. The tanks there sit miles apart, and a drive to each was the only way to know.
It does not fit every tank. The radio has to reach a receiver in a building with power, a mile or more with a clear line of sight, so a tank far out on a big pasture is a job for a satellite or cellular monitor.
The stock tank monitor, and where it does not fitQuestions about cattle and water
How much water does a cow with a calf drink in a day in summer?
About 25 to 34 gallons for the pair on a hot day: 20 to 24 gallons for the cow and 5 to 10 for her calf, by the University of Nebraska's figures. A nursing cow needs about 2 gallons for every 100 pounds she weighs when the day reaches 90°F.
How much more water do cattle drink at 90°F than at 70°F?
About 63 percent more for growing and finishing cattle and bulls, by the National Research Council's table. A 600-pound calf goes from 7.8 to 12.7 gallons a day, and a 1,000-pound steer from 12.6 to 20.6.
Does shade cut how much water cattle drink?
Yes. Mississippi State University Extension notes that shade in summer can reduce water intake. Cool water works the other way: cattle drink more, and eat more, when the water is cool, so a trough kept out of the afternoon sun helps on both counts.
Where should I set the low alert on a tank that waters cattle?
At least a day of the herd's water above the outlet, worked at the hottest weather you expect. For 30 cow-calf pairs at 25 to 34 gallons a pair, that is up to 32.6 inches on a tank 8 feet across. Watch a week of readings in the heat, then move the line.
Read next
The stock tank water level monitor
What it does on an open tank, and what it catches.
Satellite, cellular or radio
Three monitors compared, for the tank near the house and the far pasture.
How to read a water level gauge
And how to turn the reading into gallons for a tank of any width.
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