Dog Daily Water Requirement
By Manuel Villanueva  Published 2004  Revised February 14, 2024
Definitions & Formulas
 dehydration
 Dehydration in clinical practice refers to the loss of body water at a rate greater than the body can replace it.
 daily energy requirement (DER)
 DER represents the average daily energy expenditure of any animal, dependent on lifestage and activity.
 resting energy requirement (RER)
 RER represents the energy requirement for a normal but fed animal at rest in a thermoneutral environment.
 daily water requirement
 The daily water requirement of dogs and cats, expressed in milliliters/day, is roughly equivalent to the daily energy requirement (DER) in kilocalories/day (for dogs 1.6 x resting energy requirement [RER], for cats 1.2 x RER).
 daily water requirement
 70 × (weight in kilograms)^{0.75} × 1.6 = (volume in milliliters)/day
Examples
1. What is the daily water requirement of a 24 pound cocker spaniel?

Convert pounds to kilograms
 1 kilogram ≈ 2.205 pounds
 24 ÷ 2.205 ≈ 10.884

Enter the pet's weight into the water requirement equation. To calculate 10.884^{.75} use the
x^{y} exponent calculator key. Enter 10.884, x^{y} key, then .75.
 V = 70 × (weight in kilograms)^{0.75} × 1.6
 V = 70 × (10.884)^{0.75} × 1.6
 V = 70 × 5.992 × 1.6
 V = 419.440 × 1.6
 V ≈ 671.104

To convert milliliters to cups use the following equation then enter your values.
 Cups ≈ 1 milliliter ≈ 0.0338 ounces ÷ 8
 Cups ≈ 671.104 × 0.0338 ÷ 8
 Cups ≈ 22.683 ÷ 8
 Cups ≈ 2.835

To convert 2.835 cups to cups with ounces use the whole number for cups. Then multiply the remainder by 8 for
ounces.
 Cups and Ounces: cups = whole number; ounces = remainder × 8
 Cups = 2; 0.835 × 8
 Cups = 2; Ounces ≈ 6.680
So this cocker spaniel has a daily water requirement of approximately 671 milliliters per day or 2 cups and 6.7 ounces.
2. What is the daily water requirement of a 12 kilogram cocker spaniel?

Enter the pet's weight into the water requirement equation. To calculate 12^{.75} use the
x^{y} exponent calculator key. Enter 12, x^{y} key, then .75.
 V = 70 × (weight in kilograms)^{0.75} × 1.6
 V = 70 × (12)^{0.75} × 1.6
 V = 70 × 6.447 × 1.6
 V = 451.290 × 1.6
 V ≈ 722.064

To convert milliliters to cups use the following equation then enter your values.
 Cups ≈ 1 milliliter ≈ 0.0338 ounces ÷ 8
 Cups ≈ 722.064 × 0.0338 ÷ 8
 Cups ≈ 24.406 ÷ 8
 Cups ≈ 3.051

To convert 3.051 cups to cups with ounces use the whole number for cups. Then multiply the remainder by 8 for
ounces.
 Cups and Ounces: cups = whole number; ounces = remainder × 8
 Cups = 3; 0.051 × 8
 Cups = 3; Ounces ≈ 0.408
So this cocker spaniel has a daily water requirement of approximately 722 milliliters per day or 3 cups and 0.4 ounces.
General Rule
I hope you found this page interesting and informational. Although, a dog's water requirements are dynamic and very day to day. ALWAYS PROVIDE YOUR DOG WITH CLEAN FRESH WATER unless your vet specifies otherwise. Your dog is the best judge of how much water he needs. Just keep that bowl full 😁
Water Requirements for Cocker Spaniels
This applies to pets lying around the house. Pets playing outdoors will need more water.
2428 pounds
671754 ml/day
2634 pounds
713872 ml/day
Dehydration in Dogs
Dogs don't lose much water from sweating like humans. Water loss occurs through urine, feces and breaths (respiration). Exercise and strenuous activity can double or quadruple water requirements. Working dogs, such as police K9s and sled dogs are at increased risk of dehydration. The combination of environment and activity can increase canine water loss 1020 times above normal through respiration.
Causes & Risk Factors for Dehydration
 Lack of water
 Neglect
 Hot weather
 Strenuous activity
 Poor health, disease (e.g. diabetes), illness (e.g. diarrhea)
 Age: puppies and senior dogs
 Owner awareness and education
Signs & Symptoms of Dehydration
 Thirst
 Poor skin turgor
 Dry mucous membranes
 Decreased appetite
 Sunken eyes
 Increased heart rate
 Weak pulse
 Dry stool or constipation
 Difficulty walking (severe dehydration)
 Shock, death (severe dehydration)
For Dogs at Risk for Kidney Stones
 Ensure multiple bowls of fresh water are available in prominent locations in the dog's environment. This may mean providing several bowls outside as well as inside including each level of the home.
 Add small amounts of flavoring (e.g. saltfree bouillon) to make water more palatable.
 Offer ice cubes as treats.
 Use canned dog food to help prevent concentrated urine.
 If dry food is used, add liberal amounts of water.
Anecdote
This seems like a lot of water but don't forget your pet gets water from his food as well. Dry foods contain around 8% water while canned food contains about 75% water. I've search several sources on their recommendation with varying results. Information by the Canadian government suggests dogs should have 80 milliliters of water per kilogram of body weight. Veterinarian, Janet Tobiassen Crosby, recommends dogs and cats should have 30 milliliters of water per pound of body weight which comes close to the formula on this page.
I've never really paid attention to how much my cocker Gabby drinks. His bowl holds 2 ½ cups of water. It seldom goes empty but then again we're always filling it with fresh water. He's a fat boy at 36 pounds so he should need about 4 cups of water a day.
References
 Hand, M. S., Thatcher, C. D., Rimillard, R. L., & Roudebush, P. (Eds.). (2000) Small Animal Clinical Nutrition. (4th ed.). Marceline, MO: Walsworth.
 Warrington, P. D. (2001, September 17). Animal weights and their food and water requirements. Retrieved from http://www.elp.gov.bc.ca/wat/wq/reference/foodandwater.html
 Tobiassen, J. C. (n.d.). Veterinary Q & A  Should I Call The Vet? Part I. Retrieved September 19, 2005, from http://vetmedicine.about.com/cs/diseasesall/a/whentocallvet.htm
 Bohm, R. P., & Gilbert, M. H. (2012). Emergency medicine and critical care for nonhuman primates. Nonhuman primates in biomedical research, 1, 359389.
 Thomas, D. R., Cote, T. R., Lawhorne, L., Levenson, S. A., Rubenstein, L. Z., Smith, D. A., ... & Council, D. (2008). Understanding clinical dehydration and its treatment. Journal of the American Medical Directors Association, 9(5), 292301.
 Taylor, A. J., & Kuhl, E. A. (2023, October 28). EMS Canine Evaluation and Treatment of Dehydration. National Library of Medicine. https://www.ncbi.nlm.nih.gov/books/NBK597364/
 Reynolds, A. J., Sneddon, K., Reinhart, G., Hinchcliff, K., & Swenson, R. (1998). Hydration strategies for exercising dogs. Recent Advances in Canine and Feline Nutrition, 11, 259267.