Is It Safe for My Dog to Drink From Rivers, Lakes or Oceans?

Dog drinking from river
Your dog could be seriously harmed by drinking from a lake, river or ocean.

Any animal compelled to lap up toilet water probably has a cast-iron constitution, right? So what harm can come to a dog who drinks out of natural bodies of water?

Plenty, as it turns out.

Outdoor water sources can harbor organisms and chemicals that can be harmful to your dog, some of which can put you at risk for zoonotic disease as well.

Some of the Risks

Here’s just a sampling of what can lurk in outdoor water sources:

Bacteria. Water that’s contaminated with animal or human waste can contain bacteria, including species of salmonella, Campylobacter, Escherichia coli and Leptospira.

In mild cases, these bacterial infections can lead to diarrhea (which could make for a long drive home from the beach, even with the car windows rolled down). Severe infections with these organisms can be much worse. Some of these bacteria may be shed in the stools of infected dogs, and improper handling of feces can potentially lead to infections in people.

Of these bacteria, infection with the Leptospira species can be especially concerning. These bacteria are often found in marshy or muddy water and slow-moving or stagnant pools frequented by wildlife, such as raccoons, opossums, skunks and rodents. Infection in dogs, if not treated early, can result in liver and/or kidney damage and death. Organisms can be shed in the urine of infected dogs, leading to potential infection in people.

If you live in an at-risk area or like to take your dog hunting, ask your veterinarian about leptospirosis vaccines. Although these vaccines can’t offer protection against every subtype of these bacteria, they do help protect dogs against some of the more common ones.

Blue-green algae. Though not exactly a plant, these bacteria produce energy by photosynthesis. Cyanobacteria can form colonies of blooms that often float on the water's surface, especially during the hot weather of summer and early fall.

Dogs may swallow the blooms while swimming or ingest them when grooming their coats after being in the water.

Some of these blooms produce toxins, such as microcystins, which can lead to liver failure, and anatoxins, which typically affect the nervous system. Signs can begin soon after ingestion and may include vomiting, diarrhea, seizures, collapse and death.

If you suspect that your dog has swallowed blue-green algae, it’s important to get him to the veterinarian immediately. No antidote for the toxins exists, but supportive care may help your dog survive.


Join the Conversation

Like this article? Have a point of view to share? Let us know!