Because milk is nearly 90% water, lactating dairy cows — especially high producers — are losing it at a much higher rate than other animals. With most of their water intake coming from the trough, lactating cows will spend about a half hour a day drinking, sometimes at a rate of 6.3 gallons per minute. That adds up fast; depending on the size of the farm’s herd, a flow rate of 12 to 30 gallons is typical, with experts recommending the higher rate to assure flow is keeping up with demand.
Logistically, pens that have 100 or more cows should have two or more locations for drinking, all with adequate surrounding space. The authors of the article emphasized that cows tend to want to drink when they leave the milking parlor, so exit-alley access is important. They also want to rehydrate after eating, so ideally water should be available close to feed lanes. A 50-foot trip to the trough is about the maximum distance a cow should have to put in to drink, the experts recommend.
Measures for success
Water troughs can be tricky to assess for optimal herd hydration, said the authors. Again, herd size makes the difference: for 200 or less, aim to be able to accommodate 15% of the total herd at your water stations. When the herd is larger, the target accommodation should be 20%. In freestall barns, where water stations are often located at crossovers, ensure there is enough room for trouble-free water access. A 2024 Penn State Extension article notes that cows are prone to synchronizing their behavior: They will often eat and drink at the same time, so guaranteeing there are enough water stations with adequate room is crucial, especially when it comes to the more submissive members of the herd.
Trough depth should be 10 to 14 inches; any deeper and producers run the risk of feed and debris accumulating at the bottom, leading to stagnancy. Deeper troughs are also more difficult to clean, which can compound the problem. And while it’s important to have a cleaning schedule — at least once weekly — producers should also do daily spot checks to make sure the water is still clean.
Overall maintenance and checks for the plumbing system are also vital for ensuring adequate and clean water. A quick visual inspection whenever team members are in the pen should be built into the regular schedule.
Penn State Extension experts pointed out that easy access to adequate water not only helps with production goals, but supports digestion and metabolism, and helps maintain normal blood volume — all good reasons, in any season, to up your H2O game.
