This article was written as an assignment in ANS 242 Introductory Horse Management at Michigan State University, under the guidance of Course Instructor Karen L. Waite, Ph. D. Have a question for future classes? Please e-mail them to kwaite@msu.edu.

You might be wondering why it is so important that your horses have access to clean water all the time, or why they need so many gallons a day! Well the answer is simple, water is the basis of healthy living for all animals. For horses specifically, not having the correct amount of water can lead to very deadly problems such as dehydration and colic.

As a horse owner or enthusiast, it is important to know what sort of daily needs and basic nutrients your horse will require. One of the most important nutrient requirements is water, but exactly how much does your horse need every single day? According to Penn State University Extension Horse Specialist, Ann Swinker, “the average horse will intake 5-10 gallons of fresh water per day. Just like humans, different horses crave or need different water amount intakes.” She explains that water consumed varies based on the time of year because in the summer months horses can get their water from the intake of grasses, but during winter months when most of the grasses are dried, horses have to actually get their water through drinking. She also states that like humans, horses want something to warm their system when it’s cold out. This means that if you ever have a horse that is not drinking enough in the winter, it may be a good idea to try heating the water. Horses are also less likely to drink in the winter if it is partially frozen so you will want to invest in a water heater whether you have a picky horse or not.

With further research, it was found that 5-10 gallons a day is a very consistent range for most all horses. An article written by the staff at Kentucky Equine Research discussed new factors that can make the number of gallons daily vary from horse to horse. Posted in Equinews, the article stated that on any given day, a horse’s water intake varies based on “the season of the year, workload, reproductive status, diet, and climate”. They also noted that a horse might drink less than they should if the water source is “extremely cold or contaminated with dirt, feces, or other material.” In that situation, horses may drink less than they should because the water is not appealing and thus have an increased risk of dehydration. This is why it is important to check on your water tanks and buckets often because what seems like a full tank to you may really be just as good as empty to your horses.

The Kentucky Equine Research Staff made a list in their article of ways to ensure that horses always have access to water. Some key points include:

• Place one or more water sources in each stall and paddock
• Check frequently to be sure the water sources are clean and operating properly
• Empty, scrub, and refill tanks frequently during the summer
• Check that water is ice-free during the winter
• Offer water periodically to horses being exercised, so long as it’s drunk slowly and not all at once
• Offer water periodically to horses being transported

In both articles, the authors explain that the issue with horse dehydration is that it really can end in fatality. “A horse deprived of water may only live up to 3 or 6 days. After lacking water intake for two days a horse may refuse to eat and exhibit signs of colic and other life-threatening ailments” (Swinker). It is important to understand that whether your horse is just for trail riding or for high performance competition, they will not perform to your expectations if they are not properly hydrated.

Michigan State University Extension suggests that one way to check if your horse is hydrated well enough is to give them a capillary refill test. All you need to do is press your finger firmly on the upper gums just above the horse’s teeth and then remove your finger quickly. A hydrated horse will have healthy, pink, and moist gums that refill from white to pink in about two seconds. A capillary refill time longer than three seconds may mean the horse is dehydrated or may be a sign of shock.

Remember, every horse’s water intake is different and the amount that they drink from day to day varies depending on the environment and nutrient status of the horse. Generally, the best thing you can do to make sure your horse is well hydrated is to give them constant access to clean water and know them well enough to know when something is wrong.