Many dogs love drinking from puddles, creeks, lakes, and ponds while they’re out exploring. Unfortunately, even water that looks crystal clear can contain bacteria, parasites, harmful algae, or other contaminants that can make your dog seriously ill.
I learned this lesson the hard way with Henry. On the day I adopted him, I let him drink from what looked like a clean mountain creek. A day later he was diagnosed with Giardia.
Since then, I always carry fresh water wherever we go. In this guide, you’ll learn the biggest dirty water risks for dogs, what illnesses they can cause, warning signs to watch for, and simple ways to protect your pup while still enjoying outdoor adventures.
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Budget Tip:
Here's the amazing thing with dirty water risks for dogs. You may not only be saving your dog from being sick, but also saving your dog's life. While it doesn't take a lot of effort to avoid dirty water, it can be a game-changer. Of course, you also get to avoid pricey emergency vet bills in the process. This is all a huge win-win for you and your pup.
What Counts as Dirty Water for Dogs?
Simply put, dirty water is water that you wouldn’t drink. It may look clean, but you or your dog could get sick if you drank the water. You can find dirty water risks for dogs in the following forms:
- Mud puddle
- Pond water
- Rain puddle
- Lake
- Creek
- River
Dirty water could be standing or flowing water. You may not be able to tell visually or even by smell that the water is dirty.
Quick Answer: If you wouldn’t confidently drink the water yourself, or you don’t know whether it’s clean, don’t let your dog drink it either. Always bring fresh water and a folding travel bowl on walks, hikes, and trips to the park.
Discover how to keep your dog safe around water in this article.
What Makes Dirty Water Dangerous for Dogs?
This will naturally vary from location to location. But some of the most common unsafe water sources with dirty water risks for dogs are:
- Blue Green Algae
- Parasites
- Bacteria
- Sewage
- Salt
Can Dogs Drink From Lakes, Ponds, Rivers, or Creeks?
It will depend. When in doubt, have your dog drink from clean water you have with you. Consider the following unsafe water sources for your dog.
| Water source | Safe? |
|---|---|
| Rain puddle | Usually no |
| Pond | Avoid |
| Creek | Avoid drinking |
| River | Avoid |
| Lake | Avoid |
| Ocean | Avoid swallowing |
Henry’s Lesson: On the day I adopted Henry, I let him drink from what looked like a perfectly clean mountain creek. He developed Giardia and needed antibiotics. Our veterinarian told me to always bring fresh water instead because even clear water can carry parasites and bacteria.
5 Illnesses Dogs Can Get From Dirty Water
You may be shocked to learn that your dog can get sick from water that even looks clean. Also, the water may even be flowing. However, it can make your dog sick just by drinking or playing in it. Here are the top five culprits of waterborne illnesses in dogs.
1. Blue Green Algae Poisoning in Dogs
This type of dangerous water will appear very green on top. It will almost look like paint has been poured on top of the standing water. It could even have a green oil slick appearance. Any water that looks like this, you and your dog will want to avoid. Even if there are no signs prohibiting it, don’t swim, fish, or allow your dog to drink or enter this type of blue algae water.
However, if your dog does come in contact with blue green algae contaminated water, you’ll need to act quickly to get him or her to your vet.
How to avoid blue green algae
This waterborne illness in dogs is one of the easier ones to avoid since the water presents a blue green oil spill appearance. If you see a waterway that has this appearance, avoid it.
Symptoms of blue green poisoning in dogs include:
- Panting
- Vomiting
- Seizures
- Drooling
- Diarrhea
Blue green algae poisoning may also include liver and respiratory failure as well as death. Thus, the need to act quickly and avoid blue green algae water at all costs with your dog.
NOTE: At Henry’s favorite hiking spot, there are signs up currently that the lake is toxic due to blue green algae. However, don’t expect signs in all locations. Especially as the drought in the west continues, blue green algae will become more prevalent.
2. Giardia in Dogs
This is a microscopic parasite that you won’t be able to see or smell. Giardia is found in water that has been contaminated with feces. This can be human or animal feces.
Also, the water can be standing or flowing. Thus, a creek could be soiled with wild animal feces. Or it could be soiled by dogs eliminating too close to the creek. This is a very good case for always picking up your dog’s poo and not allowing your dog to defecate close to waterways.
How to avoid Giardia
Since Giardia isn’t easy to detect, the best idea is to avoid waterways you don’t know. The good thing about Giardia is that it’s not fatal, but it can make your dog sick.
Symptoms of Giardia in dogs include:
- Diarrhea
- Vomiting
- Diminished appetite
- Lethargy
If your dog is exhibiting any of these conditions, you’ll want to seek veterinary care for a proper diagnosis and treatment.
Wish you could hike with your dog without back pain? In this article, I show you how to do it.
3. Cryptosporidium in Dogs
This is another parasite that is found in infected water as well as food and feces. Again, you will not be able to tell the water is dirty simply by a visual inspection for cryptosporidium. You probably won’t be able to smell that it’s dirty water either. These parasites are microscopic.
How to avoid Cryptosporidium
Since it’s difficult to tell if water is contaminated with this parasite, the best option is to avoid waterways and give your dog only water you know is safe.
Symptoms of cryptosporidium in dogs include:
- Diarrhea
- Fever
- Lethargy
- Weakness
- Diminished appetite
The good news is that if your furry friend is in good “dog health,” he or she may not need any treatment for this parasite. However, if your dog is a puppy, senior, or has immune issues, he or she will probably need treatment.
You’ll want to consult your veterinarian either way. Also, this is another good reason to not only let your dog drink solely from water you provide, but also not to eat feces. I know that can be a tough one for some dogs, but one worth working on with your dog.
4. Leptospirosis (Lepto) in Dogs
This is a bacterium that resides in rivers, creeks, streams, and lakes worldwide. It’s considered a zoonotic disease, which simply means it can be passed from animal to human. While this harmful bacteria is most common in areas that are warmer and have a lot of rain, it can occur anywhere.
How to avoid Lepto
Lepto is passed through urine-infected water, soil, food, or bedding. Again, you may not be able to tell that a stream is soiled with leptospirosis until your dog is sick. Thus, it’s best to avoid letting your dog drink from waterways.
Symptoms of leptospirosis in dogs include:
The symptoms of lepto can vary in dogs. While some dogs will be very sick. Others will have extremely mild symptoms and recover quickly. However, if you suspect your dog has been exposed to lepto you’ll want to consult your veterinarian immediately. Here are some symptoms that could appear if your dog has been infected with leptospirosis:
- Frequent urinating
- Dehydration
- Vomiting
- Diarrhea
- Diminished appetite
- Lethargy
- Inflammation of the eyes
- Jaundice (yellowing) of skin and mucous membranes
Also, this bacterium can cause kidney and liver failure or problems.
NOTE: If your dog is at high risk for exposure to Leptospirosis, you may want to consult with your veterinarian about the vaccine for leptospirosis. This vaccine has been associated with allergy issues. However, those issues may be better than the possibility of lepto. It will be something to discuss with your veterinarian.
5. Hypernatremia in dogs
This is basically excess saltwater ingested by your dog that puts his or her system in a state of imbalance.
While it can be fun to play with your dog at the ocean or some other saltwater body, keep in mind the risks. A little ingestion of saltwater will cause diarrhea. However, your main concern will be when enough saltwater is ingested that more serious symptoms occur.
How to avoid Hypernatremia
Generally, when playing with your dog in saltwater, it’s recommended that you make your dog take a break every 15 minutes and drink clean water. You may need to squirt the clean water into your dog’s mouth to encourage drinking. However, this is thought to prevent the more serious symptoms of hypernatremia.
Symptoms of Hypernatremia in dogs include:
- Diarrhea
- Vomiting
- Dehydration
- Seizures
If your dog has these symptoms of hypernatremia, you’ll want to seek veterinary care immediately.
Other Dirty Water Risks Dog Parents Often Forget
Any stagnant water could be a breeding ground for a bacterial infection.
- Communal water bowls
- Puddles in parking lots, or anywhere else
- Flooded fields
- Runoff after heavy rain
- Standing bird baths
Don’t forget to always pack a folding or travel dog water bowl for walks, hikes, and other adventures.
How Much Money Can You Save by Avoiding Dirty Water?
You may not think that simply avoiding contaminated water could impact your bottom line, but it definitely can be huge! Consider the following for a moment.
| Issue | Possible Cost |
| Emergency vet | $100 – 5,000 |
| Antibotics | $25 – 50 |
| IV fluids | $100 – 200 |
| Bloodwork | $100 – 300 |
| Hospitalization | $500 – 2,000 |
| Fatal contamination | Heartbreaking!!! |
| Healthy dog | Priceless!!! |
Related articles:
- Dog Water Safety Tips
- How to Enjoy Dog Hiking Trails Without Back Pain
- Easy Dog Emergency Vet Visits Tips
- How to Find the Best Veterinarian
- Dog Toilet Drinking Harmful? Or Completely Gross?
- Happy Dog Hiking Trails Without Back Pain
- Easy Hack To Remove Sap From Your Dog’s Fur
FAQs about Dogs Drinking Dirty Water
Can dogs drink creek water?
No, dirty water risks for dogs can be in creek water. Even clear flowing water may be contaminated water and contain Giardia, Leptospira, or other harmful organisms.
Can dogs drink lake water?
Avoid it whenever possible because lakes may contain harmful algae, parasites, or bacteria.
Is puddle water dangerous for dogs?
Yes. Puddles can contain bacteria, chemicals, antifreeze residue, parasites, or runoff.
How do I know if my dog got sick from dirty water?
You’ll want to watch for these symptoms:
- Diarrhea
- Fever
- Lethargy
- Weakness
- Diminished appetite
Should I bring water on every walk?
Yes. Bringing fresh water is the safest option. Also, remember that your dog will need a folding bowl like this one.
Dirty Water Risks For Dogs To Avoid
Dirty water isn’t always dirty-looking. Some of the most dangerous bacteria, parasites, and algae are completely invisible, which makes prevention the safest choice.
After Henry’s Giardia diagnosis, I never leave home without fresh water and a collapsible travel bowl. It’s a simple habit that helps us enjoy hiking and outdoor adventures without worrying about what might be hiding in a puddle, creek, or lake.
A little planning today can save your dog from serious illness and save you from an expensive emergency vet visit later.
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I am so blessed Layla hates water but the water in her bowl. She will not go near puddles etc but I am fully aware of the health hazards from dirty water and she does get the Lepto shot every year because if we are in dog parks and there is mud and she walks through it I would rather be safe than sorry, Great post and eye opener
You are very lucky indeed. It sounds like Layla knows exactly how to stay safe and avoid dirty water. Good job Layla and Ruth!
I’m always really careful to not let my two drink from outdoor water sources. I worry a lot especially about lepto, even though we do live in a colder climate. Cases do still pop up here though, and we live in a wooded area with a lot of wildlife. My senior dog is vaccinated yearly against lepto, but my younger dog can’t be because he reacts to the lepto vaccine.
Lepto is definitely something to be aware of in all areas. It’s amazing how toxic bacteria are popping up in areas we never expected years ago. I’m glad you’re keeping your eyes on your pups. Although you can only vaccinate your one dog, it’s good you know the other can’t tolerate the vaccine. You are definitely a great dog parent.
This is an excellent reminder for dog parents to remain vigilant.
As for my dogs, though, I have to assess what is dirty water and what is not constantly. My dogs prefer any water they can find to the fanciest water I can offer. Puddles, creeks, water pooled in tarps–anything goes. At some point, I had to accept that my dogs would be dogs and would do what they do. Given how much time they spend outdoors, I find it impossible to chase them around and nag them over everything.
So by now, my strategy is to monitor for water that appears truly nasty and keep them away from just that. It’s a calculated risk–who wants to be nagged all day?
I get paranoid about the blue green algae–over time, I had to learn which green stuff in the water is harmless and which is too risky to gamble with.
One time, I shoveled out the entire content of our ditch because it looked suspicious to me. Yes, regular shovel and a lot of sweat. Did you know you can showel out your ditch? LOL
You’re right you do sometimes have to make an educated choice. Blue green algae are super toxic and definitely one to avoid at all costs. Or if your dog has immunity issues, you need to be extremely cautious.
I didn’t know you could shovel out a ditch. I’ve dug ditches to get water to drain. But never thought to shovel out the water. I wouldn’t know where to put the water. What did you do with the water? Thankfully, the ditches I’ve dug weren’t for toxic water. They were just for water that was standing and I didn’t want the water to become an issue. Kudos to you for thinking outside the box. I’m sure you didn’t need any other exercise that day. 💪
Yikes! I never had an issue with my cats exploring outdoors as they were indoor-only cats; however, reading all the potential hazards with dirty water is why I’m not a fan of lakes or green/brown water. Eeek! It’s great that you now take precautions and bring your water bowl and clean water for your dog.
I’m glad you found this article educational. It can be a bit scary with dirty water. But you can easily take precautions to be safe with your dog, cat, or other pets. Thanks for the continued support, Kamira!
I can believe the danger in dirty water! Here in New Zealand in summer some rivers have what is called Toxic Algae (it even SOUNDS icky!) it is lethal, it kills dogs so local councils always put out alerts when even the smaller puddle of this evil stiff is found!
I wonder if toxic algae in New Zealand is blue green algae. It is extremely toxic and very dangerous. Every year I hear of people and animals dying due to contact with it. Either way, I’d be cautious around those toxic waterways. You wouldn’t want to come in contact with that kind of toxic water. I may have to research what exactly toxic algae is in New Zealand. Thanks for sharing and bringing this type of algae to my attention, Marjorie!
The dogs we have now, don’t like puddles or bodies of water, but we’ve had dogs who loved to swim, splash, and drink out of anything. This information is very important and I’ve shared it with my favorite dog lovers.
You’re very lucky that your dogs know how to stay safe and avoid dirty water. Thanks for the continued support, Beth!
Living in Michigan, I know there are all kinds of crazy things in water. Our beaches get closed at least once per year due to ecoli and other issues. I hadn’t really thought about how difficult it would be with a dog though. This is very interesting! It’s definitely worth carrying a few bottles of water to prevent those diseases from occuring in your dog.
Oh yes, ecoli can be a big issue depending on where you live. Thank you for that reminder. I didn’t include it in this article because it’s generally not as prevalent as those dirty water issues listed. However, I may need to go back and do an update.
You are absolutely right. Carrying clean water for you and your pets is definitely worth it. Thanks for the comments and the ecoli reminder.
My Husky Icy always tried to drink from creeks, streams & lakes. I was always trying to keep her away from wild water!
I LOVE that phrase “wild water.” That is it exactly! It can be a challenge, but it’s definitely worth the effort. I bet Icy did love drinking from wild water. She was such a great pup!
It’s so tempting to let my dogs swim in any water we come across but I hear so many horrible stories of people losing their pups to Blue Green Algae Toxicity. We hold off if we are anywhere near golf courses or farmlands since the risk is higher with the chemicals they use. We also stick to moving water. And of course, carry our drinking water because of all the other issues you mentioned
Even moving water can be dangerous. The creek that Henry drank from on the day I adopted him was a creek with rather fast spring moving water. I thought it would be safe with that much moving water. I learned a lesson at poor Henry’s expense.
Excellent article, Terri! And so, so important for dog parents to be aware. I am so glad Henry got over his bout of giardia, and wouldn’t you think a flowing stream would be safe, clean water? I have also had issues with my huskies with giardia (ugh), and couldn’t for the life of me figure out how they contracted it since I didn’t go hiking with them and they stayed on my well-policed property that contained no ponds or streams. I finally discovered the culprit–squirrel and opossums (crazily) visited our yard, only to be chased away by my five…however, they must have had droppings left behind and in the rain puddles under the maple trees, where my dogs loved to dig holes in! Yikes! And when one gets giardia, they all need to get treated. (Hand slap to the forehead). So after that ordeal, whenever it rained, I waited until all the puddles were completely dried up before letting them in the yard!
This is such important information I’m sharing with my readers!
That is amazing that your FiveSibes were getting sick from squirrels and opossums visiting your yard. I need to keep that in mind since we have bears, bob cats, mountain lions, raccoon, squirrels, chipmunks, deer, wild horses, and I’m sure a few other things I’m missing. Henry does love to sniff where they’ve all been the next day. I never let him sniff anything that looks wet, but he’s so quick it could happen in the blink of an eye. This is a great observation! Thanks Dorothy for sharing and for your kind words. I really appreciate it!