Your State's Algal Bloom Advisory Was Not Written for Your Dog

There is a number for your dog. It is not the number on the sign.

Oregon publishes both in one document. In its Advisory Guidelines for Cyanobacteria Blooms in Recreational Waters, updated May 2024, Table 2 sets the recreational use value for microcystin at 8 micrograms per liter. Table C-4, in Appendix C, sets the dog-specific value for the same toxin at 0.2. For saxitoxin the two numbers are 8 and 0.02.

Then the document says which one gets used: the dog values are for informational purposes, to educate pet owners about the susceptibility of dogs, and “are not used as a basis for issuing public health advisories.” Oregon’s public FAQ puts it in one sentence: “OHA has established RUVs for people and dogs, but advisories are only issued when there are human health concerns.”

That is not a criticism of Oregon. It is one of the few states that derived a dog number, published it, and said plainly what it is and is not used for. The point is what it means for the sign at the boat ramp: a posted advisory is a statement about people, and reading it as a statement about your dog is a category error that the issuing agency has already warned you about.

This page covers freshwater cyanobacteria, also called blue-green algae, in lakes, reservoirs, rivers and ponds. It does not cover marine or coastal blooms or red tide. It holds no live data, so it cannot tell you the status of your lake today; it can tell you where your state publishes its status, what the words mean in your state, and what the status is measuring. It gives a clear get-to-a-vet trigger but no treatment, dosing or home care for a sick animal.

The Federal Numbers Are Human Numbers, and EPA Says So

In 2019 EPA issued recommended recreational criteria for two cyanotoxins: 8 micrograms per liter for microcystins and 15 for cylindrospermopsin. EPA’s current page, last updated June 24, 2026, describes them as concentrations “at or below which human health is protected while swimming or participating in other recreational activities in and on the water.” States, territories and authorized Tribes can consider adopting them into their water quality standards or use them as the basis of swimming advisories. Nothing binds anyone.

The underlying technical document, EPA 822-R-19-001, is explicit about scope. It says that although animals have been poisoned and killed by cyanotoxins, “values protective of animals such as dogs and livestock are not generated in this document.” Its section 7.8 then summarizes guidelines several states developed for animals. The federal document declines to produce an animal number and points to the states that made their own.

Why an animal is not a small person here

Section 7.8 explains that livestock and pets can be exposed to higher concentrations than humans because they consume cyanobacterial scum and mats and drink contaminated water. It says mats and scums can hold thousand-fold to million-fold concentrations of cyanobacterial cells, and that published microcystin concentrations have ranged up to 24 mg per liter from scum material.

A swimmer meets the water column and a small incidental amount of it. A dog drinks the water on purpose, eats material dried at the edge, and licks the rest off its coat. Two of those three exposures concentrate the toxin rather than dilute it. EPA also notes that the effects on domestic and companion animals are likely under-recognized because many cases are misdiagnosed, few are biochemically confirmed and fewer still are reported, so any case count is a count of what got recognized and reported.

Idaho Department of Environmental Quality states the asymmetry: no human deaths in the United States have been caused by cyanotoxins, but pet, livestock and wildlife deaths have been reported throughout the United States and the world. A warning system calibrated to humans will lag the thing you care about.

The Word on the Sign Has No National Meaning

Checking for an advisory is good advice. The problem is assuming the word carries a fixed meaning. Six state frameworks use six vocabularies that do not map onto each other.

State	Tier names, lowest to highest	Where “Warning” sits	Where “Advisory” sits	Do tier definitions mention pets?
California	Caution (Tier 1), Warning (Tier 2), Danger (Tier 3)	Middle of three	Not a tier name	Triggers are stated to protect human and animal (dogs and livestock) health
Kansas	Watch, Warning, Hazard	Middle of three	Not a tier name	Yes, Watch and Warning each carry a pets line
Utah	Warning Advisory, Danger Advisory	Lower of two	In both names	No; animals appear only as a trigger for issuing an advisory
Oregon	Precaution, Advisory (plus Lifted)	Not a tier name	Highest tier	Yes, separately from the human line
Wyoming	Under Investigation, Bloom Advisory, Toxin Advisory	Not a tier name	In two of three names	Not in the tier definitions; the pets and livestock instruction is in the general guidance
Idaho	Health Watch, Health Alert, Health Advisory	Not a tier name	Highest tier name	Yes; the middle tier names pets and livestock first

The conclusion is this site’s own, not any agency’s: the word on a sign is not information until you have read that state’s definition of it. Warning and Advisory rank in opposite directions depending on which side of a state line the lake sits on.

California. The trigger levels for posting planktonic advisory signs come from the California Cyanobacteria and Harmful Algal Bloom Network. The Network adopted them as voluntary guidance, not policy or regulation, in 2016. A separate benthic (bottom-mat) guidance was approved in March 2025. The planktonic triggers:

Criteria	No Advisory	Caution (Tier 1)	Warning (Tier 2)	Danger (Tier 3)
Total Microcystins	< 0.8 µg/L	0.8 µg/L	6 µg/L	20 µg/L
Anatoxin-a	Non-detect	Detected	20 µg/L	90 µg/L
Cylindrospermopsin	< 1 µg/L	1 µg/L	4 µg/L	17 µg/L
Cell density of potential toxin producers	< 4,000 cells/mL	4,000 cells/mL	not addressed	not addressed
Site-specific indicators	None present	Discoloration, scum, algal mats, soupy or paint-like appearance; suspected illness	not addressed	not addressed

Two things matter for a dog. A Caution advisory can be posted on appearance or a suspected illness with no toxin number measured. And California’s footnote says action levels are met when one or more criteria are met: one is enough.

Kansas. Kansas Department of Health and Environment has three levels. Watch means a harmful algal bloom is possible and may be present, and water may be unsafe for humans and animals. Warning means a bloom is expected or present and water is unsafe for humans and animals. Both tell people not to let pets eat dried algae or drink contaminated water. Hazard means extreme conditions exist, and KDHE recommends closing part or all of the lake. Kansas also says not to let livestock, pets, or working animals such as hunting dogs drink from affected waters, eat dried scum on shorelines, or lick their fur after exposure.

Utah. Utah has two levels, and Warning is the lower. A Warning Advisory says to “Avoid primary contact recreation (e.g., swimming, waterskiing, wading)” and notes potential for short-term effects such as rash, nausea, vomiting and diarrhea, or long-term illness. A Danger Advisory says to “Stay away from the waterbody” and adds potential for death. Utah’s guidance page mentions animals once, as a trigger for the health department: reports of human or animal illness or death plausibly linked to cyanobacteria make an immediate public health advisory recommended. A sick animal is an input to the advisory system there, not its audience.

Oregon. Advisory is the top tier. An Advisory means cyanotoxin levels are confirmed unsafe for swimming, or conditions indicate they may be, and Oregon’s definition says toxin levels are unsafe for pets. Precaution means a bloom is confirmed or cyanotoxins are present “at levels that are safe for human recreation,” and the definition adds: “Toxins levels may still be unsafe for pets.” Precaution is defined as human-safe and the pet line as an open question, so the two answers have come apart in the definition itself. An Advisory is downgraded to a Precaution when testing shows safe levels for human recreation but a bloom or toxins remain, so the downgrade is triggered by the human number. A Precaution is lifted when testing shows cyanotoxins are not present or the bloom is visibly gone.

Putting those together is this page’s reasoning, not Oregon’s: one of the two routes out of a Precaution is visual, and Oregon’s guidelines say a bloom can disappear visually while toxins remain. That does not make a lifted Precaution meaningless. It means it can rest on the one form of evidence the guidelines say can be wrong.

Wyoming. Wyoming separates a bloom being present from toxins being measured. A credible report puts a waterbody Under Investigation. If the Department of Environmental Quality verifies a bloom, the Department of Health issues a Bloom Advisory. If cyanobacteria abundance or cyanotoxin concentrations exceed public health thresholds, it keeps or issues a Bloom Advisory or issues a Toxin Advisory. Wyoming also says “there may be waterbodies with HCBs that the Wyoming Department of Health is not aware of,” and that waterbodies with an advisory are not closed, since blooms may be present only in certain areas and conditions change frequently.

Idaho. Idaho has Health Watch and Health Alert while toxin results are pending, and a Health Advisory, issued as a press release, where an active, toxic bloom is confirmed. The middle tier, Health Alert, indicates a high level of risk to pets and livestock. The top tier, Health Advisory, is described as a high level of confirmed risk to humans. The tier that names your dog first is the middle one. Both upper tiers list allowing animals in the water under DO NOT, and the lowest tier softens it to USE CAUTION.

A Worked Example on One State’s Live Table

As of August 15, 2026, Oregon’s Blue-Green Algae Advisories page listed 34 waterbodies: 23 at Precaution, 8 at Advisory, 2 at Precaution Lifted and 1 at Permanent Advisory. Of the 23 Precaution rows, 15 carried a numeric toxin measurement, 3 read Non-detect and 5 showed none. Twelve of the 15 numeric rows were above at least one of Oregon’s dog values (0.2 for microcystin, 0.02 for saxitoxin, 0.4 for anatoxin-a). The microcystin figures Oregon’s table published for ten of them ran from 0.22 at the Willamette River at Portland up to 3.86 at Cullaby Lake; the other two were Clackamas Cove at saxitoxin 0.15 and Hyatt Lake at anatoxin-a 0.54. Three numeric Precaution rows were below every dog value: Fern Ridge Reservoir at 0.17, Devils Lake at 0.18 and Ochoco Reservoir at 0.15. So the milder status is sometimes mild for a dog too. It is simply not what the status tells you.

The comparison is this page’s arithmetic, not Oregon’s. Oregon publishes the table and the dog values in separate documents and says the dog values are not used to issue advisories. Its guidelines describe them as a resource for veterinarians treating dogs believed to have been exposed, which is close to how they are used here. A state advisory page is also a snapshot: that page carried a notice that it would not be updated August 8 to 18, 2026, with a pointer to the advisory map and 1-877-290-6767.

The States That Publish a Dog Number, and What Theirs Cover

EPA’s State & Tribal Toxin Thresholds page, last updated July 13, 2026, compiles the thresholds states use for advisory decisions. Each dog row is narrower than it first appears.

Oregon: informational, not operational. EPA lists Oregon’s Dog Information Values as anatoxin-a 0.4, cylindrospermopsin 0.4, microcystin 0.2 and saxitoxin 0.02 micrograms per liter, against human values of 15, 15, 8 and 8 in Table 2. Oregon also notes that its dog values are below the guideline values for drinking water affected by cyanotoxins, so it recommends owners supply pets with bottled water or water from alternative sources when a drinking water advisory is in place.

Indiana: real thresholds, one dog park. Indiana Department of Environmental Management publishes this table (µg/L):

Exposure Reference Values	Microcystin	Cylindrospermopsin	Anatoxin-a	Saxitoxin
Human Recreation Advisory	8	6	8	0.8
Dog Recreation Advisory	0.4	0.5	not published	not published
Dog Recreation Prohibited	0.8	1.0	0.4	0.05

For microcystin, Indiana’s dog advisory value is one-twentieth of its human value. Now the qualifier: the warning or closure applies to dog owners using the Fort Harrison State Dog Park. Indiana says the dog numbers come from other states’ work: California’s OEHHA for microcystin, anatoxin-a and cylindrospermopsin, and the Oregon Health Authority for saxitoxin. Everywhere else, the sampling program does something else. Indiana notes its test results are for a beach where pets are not permitted to swim, and asks owners to “keep pets out of the water along shallow banks and the shoreline” too, which is water nobody tested. That is an honest description of what a beach monitoring program covers.

California and the other end of the scale. EPA’s 2019 document, section 7.8.1, describes California’s 2012 work: an acute action level of 100 micrograms per liter for microcystins and 200 for cylindrospermopsin, with subchronic canine water values of 2 and 10 in Appendix H. Acute refers to exposures in a single day; subchronic to exposures over multiple days. California’s acute figure of 100 and Oregon’s 0.2 are both about dogs but answer different questions. Oregon’s is an owner-education value, not an exposure-duration figure. That reading is this site’s, not either state’s, and neither number is presented as a line below which a dog is safe.

Everyone else. EPA says other states mention animal poisoning in their guidelines but give no values for livestock or companion animals. It gives Ohio as an example: EPA’s 2019 account of an Ohio 2016 document says Ohio includes pets in its public health advisory at 6 micrograms per liter for microcystin and 5 for cylindrospermopsin, with a disclaimer that the thresholds protect humans and may or may not protect animals. That is EPA’s characterization of a 2016 Ohio document, and Ohio’s current program may differ.

What the Advisory System Cannot See

Not every waterbody is sampled. Idaho says it cannot continuously monitor every waterbody. Kansas samples public use lakes only in response to complaints of illness or sightings, so the first sick animal is part of the detection system. Wyoming says its program focuses on publicly accessible waterbodies used for full-body contact recreation, so your neighbor’s pond is outside every program on this page.

The tested spot is not the dog’s spot. EPA says wind-driven currents can amass blooms on shorelines, and those accumulations are much larger than blooms in open water. Indiana’s samples come from a beach where pets do not swim. Together, and this is our reasoning: the wind concentrates material at the shoreline, the shoreline is where a dog wades, drinks and scavenges, and the sample is often drawn from a swimming area the dog is not in.

The satellite cannot see the shallows. EPA’s CyAN freshwater forecast covers over 2,000 of the largest US lakes and reservoirs, with a stated overall prediction accuracy of 90 percent, and EPA says it is not meant to replace regular sampling. EPA also says the satellite generally does not resolve shallow areas along the edge of a lake, small embayments or narrow areas, and the CyAN app covers water bodies of roughly one square kilometer or greater. The shoreline edge, the small embayment and the small pond are where a dog is most likely to be in the water, and where the product is weakest. That join is ours.

There is no national live lookup. As of August 15, 2026, EPA’s HAB Advisories, HAB Forecasts, CyAN and State and Tribal pages did not publish the current advisory status of a named waterbody, and each routes to state programs. EPA’s HAB Advisories page compiles state-reported data monthly into a national time-lapse map and bar graph, which is a research product, not a lookup for Saturday’s trip. That describes those pages on that date, not every tool in existence.

Where the Dog Gets Exposed

EPA lists five routes for pets: drinking toxin-contaminated water, swimming in waters with a HAB, eating HAB mats, eating contaminated animals such as fish or shellfish, and licking toxins off their fur. Oregon says the primary route is ingestion: drinking from a cyanobacteria-filled lake or pond, licking fur after swimming, or eating dried cells along the shoreline. California says animals are attracted to the taste and smell of HABs, that dogs lick algae caught in their coat, and that dogs scavenging the shore may eat drying clumps. Indiana notes scum can attach to a dog’s coat and be swallowed during self-cleaning.

California’s portal adds routes no other source here covers: contact or ingestion at residential ponds or pools, ingestion of blue-green algae health supplements, and inhalation of airborne droplets or mist containing algal material or cyanotoxins. Its 2018 dog owner factsheet describes the supplement route as supplements containing blue-green algae that may unintentionally include HAB toxins. This page does not extend that into advice about any product.

For a farm or hobby pond, Indiana’s Board of Animal Health lists fencing off downwind drinking areas and using other water sources among its prevention steps. No monitoring program on this page covers a private pond.

It is not only dogs

California says all domestic animals are at risk following contact with a potentially HAB-impacted water body, that illnesses have been reported in cattle, horses, sheep, pigs, chickens and turkeys, and that most were fatal and associated with visible scum and algal mats. It adds a feed route: livestock may eat feed products that contain blue-green algae. It advises checking livestock water supplies frequently and keeping animals off water with visible HABs. Wyoming’s guidance covers pets and livestock together. The agency sources here contain no cat-specific cyanotoxin guidance; that is a statement about these sources, not a finding that none exists.

Looking at the Water Is Not a Test

EPA’s dog page gives three signs: slimy or foam-like scum or mats on the surface, odd color (blue, bright green, brown or red, like paint floating), and a nauseating smell that only some harmful algae produce. Indiana’s Board of Animal Health adds that cyanobacteria picked up disperses in the water rather than hanging together in a stringy mass, which distinguishes it from harmless filamentous algae. California maintains separate guidance for benthic mats, which are attached to the bottom, floating, or stranded along the shore, and stranded material sits where a dog scavenges.

Now the limit. EPA says: “You cannot tell if a bloom is harmful by looking at it, so it is best to use caution and stay away.”

The reverse failure is documented in Oregon’s May 2024 guidelines: between August 21 and August 30, 2009, “four dogs died of acute anatoxin-a poisoning shortly after drinking water from Elk Creek and the Umpqua River” at Elkton. Samples taken September 1, 2009 found no detectable toxigenic cyanobacteria in one set, but other samples from the same areas showed anatoxin-a at 0.5 µg/L and microcystin at an average of 15 µg/L, 1.5 times the advisory threshold then in force of 10 µg/L. Two qualifiers: those samples were above the 2009 threshold, so not every number said the water was fine, and the deaths came before any sampling. The document also says: “There was no visible bloom or scum reported in that area of the creek when these fatalities occurred.” Oregon removed cell count data from its advisory issuing and lifting protocol because of uncertainty about cell densities, toxin production and exposure.

The guidelines add that cyanotoxins can be released during bloom formation and as a bloom declines, and can take time to degrade after a bloom has dispersed, so a bloom can look gone while toxins remain. Visible scum is a reason to leave. Clear water is not a reason to stay.

Treatment Is Not the Answer Here

This site has pages about making questionable water safe for an animal: our tablets versus filter comparison and our dog water filter guide. They deal with pathogens such as bacteria, viruses, giardia and cryptosporidium. A cyanotoxin is a different hazard and the methods do not carry over.

Idaho Department of Environmental Quality says effects can be more serious in animals, which are more likely to drink the water, lick toxic cyanobacteria from their fur or eat toxic mats. “Boiling water does not remove cyanotoxins and will concentrate the toxins.” Idaho adds that “Most portable drinking water filtration products (like those used for backpacking) are not effective at removing cyanotoxins.” Note the word Most; Idaho does not say no product touches them, and neither do we. Wyoming says: “Boiling, filtration and/or other treatments will not remove toxins.” Boiling is not merely a wasted effort; Idaho says it concentrates the toxin.

Our own reasoning for why: a filter strains organisms out by size and boiling kills them with heat, but a cyanotoxin is a chemical already dissolved in the water. Killing the cyanobacterium does not remove what it released, and breaking the cell can put more into the water. That is why the correct move at a bloom is a different water source.

Indiana’s Board of Animal Health warns pond owners: “Do not treat blooms with algaecides or herbicides as they break open the bacteria cells. This will lead to a rapid release of toxins in the water.” The same page also lists treating the pond with copper sulfate or algaecides among prevention methods, and advises checking the manufacturer’s safety precautions and fencing livestock away for several days after treatment. Those pull in different directions. If you are deciding whether to treat a pond your animals drink from, ask your veterinarian or your state extension service.

For a household water advisory, our page on what a boil water advisory tells you to do for pets covers the advisory types and where boiling is and is not the answer.

When There Is No Number at All

Three states say they cannot sample everything, and eighteen of the fifty-one state-level entries in EPA’s threshold compilation list no recreation threshold. EPA’s page attaches a qualifier: it lists only thresholds for which publicly accessible information was available, so a blank means EPA did not find one, not that the state has none. Check your state agency’s page before concluding anything.

Where there is no number, EPA and Idaho publish the same default. EPA: “When in doubt, stay out!” Idaho: “When in doubt, stay out of the water.” Oregon’s FAQ turns it into habits: stay out of the water in or around a bloom and keep children and pets away; never drink or cook with affected water; and although toxins are not absorbed through the skin, and a red, raised rash can develop after contact, wash yourself or your pet thoroughly with a clean source of water and soap if available. Skin contact is not the main danger. Skin contact followed by grooming is, which is why the rinse matters more for an animal.

The practical version for a lake you cannot get information about: bring the animal’s water so the lake is never the drinking source, keep it off the shoreline where dried material accumulates, rinse it before it grooms, and treat any unexpected illness in the next few days as a veterinary call.

Rinsing, Symptoms, and the Vet Call

Agencies publish rinse instructions that do not fully agree, so here they are separately:

Source	Rinse with	Protection for the person	Do-not-lick instruction
US EPA, How to Protect Your Pooch	A thorough rinse in clean, fresh water	Wear gloves	Not stated on this page
US EPA, exposure page	Tap water as soon as possible	Not addressed	Do not let your pet lick fur after swimming in contaminated water
Indiana Dept. of Environmental Management	Soap and water immediately to remove the toxin	Not addressed	Do not let them lick the algae off their fur
Idaho Dept. of Environmental Quality	Soap and clean water, right away	Not addressed	Not stated in this passage
Oregon Health Authority	A clean source of water and soap if available	Not addressed	Not stated in this passage
California Water Quality Monitoring Council	Clean water after lake or river play	Not addressed	Not stated in this passage
California OEHHA 2018 factsheet	Clean water after water contact	Not addressed	Never let your dog eat scum or algae

Wyoming also says to rinse off with clean water as soon as possible and contact a doctor or veterinarian.

Only EPA’s dog page mentions gloves. That is worth acting on, and the reasoning is ours: if the material on the coat is dangerous enough that the animal must not lick it, it is on your hands while you scrub. None of these instructions names the lake as the rinse source. At a boat ramp there is usually no tap, and a thorough rinse takes far more water than the bottle you packed for drinking, so carry rinse water in addition to drinking water, and do not rinse the animal in the waterbody you are trying to get it out of. With no clean water, stopping the licking until you reach some is the step EPA and Indiana each publish.

Timing and symptoms. EPA lists excessive salivation, fatigue, difficulty breathing, vomiting, diarrhea and seizures, and says “Death can occur within hours to days of exposure.” EPA’s dog page says “Symptoms can arise anywhere from 15 minutes to several days after exposure” and to take pets to the vet immediately for diarrhea or vomiting, weakness or staggering, or drooling, difficulty breathing or convulsions. Indiana’s Board of Animal Health says to contact a veterinarian immediately: “Animals may die within minutes of clinical signs appearing, but can survive for several hours or up to two or more days after exposed.” It adds that if the animal has consumed a lethal amount, no antidote exists, and that sometimes animals are found dead with no signs observed. Idaho’s page tells anyone with symptoms of cyanobacteria exposure to check with a healthcare provider or veterinarian, and says to call 9-1-1 in an emergency.

California’s list is the longest: loss of energy, loss of appetite, vomiting, stumbling and falling, foaming at the mouth, diarrhea, convulsions, excessive drooling, tremors and seizures, and rash. Its last item is the one to carry: “Any unexpected sickness that occurs within a day or so after being in contact with water.”

On the phone. California warns that doctors and veterinarians may not be familiar with cyanotoxin exposure symptoms, potential treatment or how to report it. So name the exposure: say the animal was in a lake, pond or river, whether there was visible scum, and when. California and Vermont each maintain a fact sheet for veterinarians on this exposure. This page publishes no treatment; if your animal is symptomatic, get to a veterinary practice quickly with an accurate exposure history.

Reporting. In several states reporting is how the next family finds out. Kansas samples in response to complaints. Oregon’s advisories page has three reporting forms, including an Animal Illness Reporting Form. Wyoming asks that human or animal illness be reported to its Department of Health. Indiana’s Board of Animal Health asks veterinarians to report exposure incidents. EPA’s dog page ends: “Report the bloom to your state’s health department.”

Finding Your State’s Page

EPA’s State & Tribal HAB Programs and Resources page (last updated July 15, 2026) is the national starting point. It is a link directory of independent programs, not a dashboard, and agencies change their websites on their own schedules. It covers all 50 states and the District of Columbia, lists no US territories, and lists no Tribal programs in its alphabetical section; EPA lists six Tribal entries on its Toxin Thresholds page instead. Some entries in it are dead, lead to a front page, or are titled for one agency and link to another. The table below leaves out dead links, front pages and non-agency entries, and names entries by the agency the link actually reaches. If a link fails, search from the agency’s own site rather than concluding the state publishes nothing.

State	Agency pages EPA’s directory lists
Alabama	Alabama Department of Environmental Management, ADEM/ADPH Coastal Alabama Beach Monitoring Program
Alaska	Alaska Harmful Algal Bloom Network (AHAB)
Arizona	Arizona Harmful Algal Blooms, Arizona Department of Environmental Quality Arizona Water Watch Arizona Department of Health Services - Harmful Algal Blooms
Arkansas	Arkansas Department of Environmental Quality, Online Harmful Algae Bloom Complaint Reporting Form Arkansas Water Resources Center, Algal Blooms in Arkansas Streams, Ponds, and Lakes (pdf) Arkansas Department of Environmental Quality - Harmful Algal Blooms
California	California HAB Portal California Office of Environmental Health Hazard Assessment (OEHHA) Cyanobacteria Harmful Algal Blooms (HABs) and Cyanotoxins in Recreational Waters
Colorado	Colorado Parks and Wildlife Water Conditions Statewide Colorado Department of Public Health and Environment, Toxic algae
Connecticut	Connecticut Department of Energy and Environmental Protection, Blue-Green Algae Blooms Connecticut Department of Public Health Section, Blue-Green Algae Blooms Connecticut Long Island Sound Monitoring
Delaware	Delaware Department of Natural Resources and Environmental Control, Division of Water: What is a Red Tide? Delaware Health and Social Services Frequently Asked Questions: Cyanobacteria (pdf) Delaware National Resources and the University of Delaware’s Citizen Monitoring Program
District of Columbia	District of Columbia Department of Energy and Environment, Algae Blooms in District Waters
Florida	Florida Department of Environmental Protection: Blue-Green Algae Information Florida Department of Environmental Protection Bureau of Labs, Biology Section Florida Fish and Wildlife Conservation Commission: Blue-Green Algae (Cyanobacteria) Florida Department of Health, Bureau of Environmental Health, Aquatic Toxics Program Protecting Florida Together: Water Quality Status Map Florida Fish and Wildlife Conservation Commission: Red Tide Current Status Blue-Green Algae Task Force South Florida Water Management District: Addressing Blue-Green Algal Blooms
Georgia	Georgia Department of Public Health, Coastal Health District, Harmful Algal Bloom Georgia Department of Public Health, Coastal Health District: Frequently Asked Questions About Blue-Green Algae (Cyanobacteria) and Their Toxins Georgia Department of Natural Resources, Environmental Protection Division, Harmful Algal Blooms
Hawaii	Hawaii State Department of Health Disease Outbreak Control Division: Stinging Seaweed Disease (Lyngbya) Hawaii State Department of Health Disease Investigation Branch: Ciguatera Fish Poisoning (pdf)
Idaho	Idaho Department of Environmental Quality HABs Advisories Idaho Department of Health and Welfare: Harmful Algal Blooms
Illinois	Illinois EPA, Harmful Algal Blooms Illinois Environmental Protection Agency: Reporting a Harmful Algal Bloom
Indiana	Indiana State Board of Animal Health, Blue-Green Algae Indiana State Board of Animal Health, Blue-Green Algae sampling resource list Indiana Department of Environmental Management, Blue-Green Algae Indiana State Department of Health, HAB Map
Iowa	Iowa Department of Health and Human Services, Harmful Algal Blooms Iowa Department of Natural Resources, Beach Monitoring
Kansas	Kansas Department of Health and Environment, Blue Green Algae
Kentucky	Kentucky Energy and Environment Cabinet, Harmful Algal Blooms, Division of Water
Louisiana	Louisiana Department of Environmental Quality - Harmful Algal Blooms
Maine	Maine Department of Environmental Protection, Algal Toxins Maine Department of Marine Resources: Red Tide in Maine Maine Department of Environmental Protection, Blue Green Algae Map
Maryland	Maryland Department of Natural Resources, Harmful Algal Blooms in Maryland Maryland Department of the Environment, Algae (current conditions)
Massachusetts	Massachusetts Department of Public Health, Environmental Toxicology Program, Algae
Michigan	Michigan Department of Environmental Quality: Harmful Algal Blooms
Minnesota	Minnesota Department of Health Blue-Green Algal Blooms and Microcystin Minnesota Department of Health Harmful Algal Blooms Fact Sheet Minnesota Pollution Control Agency, Blue-green Algae and Harmful Algal Blooms
Mississippi	Mississippi Department of Environmental Quality: Beach Monitoring Program Mississippi State University Extension: Planktonic Algae
Missouri	Missouri Department of Natural Resources, Harmful Algal Blooms and Blue-Green Algae
Montana	Montana Department of Public Health and Human Services: Public Health & Safety: Harmful Algal Blooms Montana Department of Environmental Quality Harmful Algal Blooms Page
Nebraska	Nebraska Department of Health and Human Services and the Nebraska Department of Environmental Quality: Fact Sheet - Precautions and facts regarding toxic algae at Nebraska Lakes Nebraska Department of Environmental Quality: Beach Watch HABs
Nevada	Nevada Department of Wildlife, Harmful algae blooms Nevada Division of Environmental Protection - Harmful Algal Bloom Program
New Hampshire	New Hampshire Department of Environmental Services: What You Should Know About Cyanobacteria
New Jersey	New Jersey Department of Environmental Protection Harmful Algal Blooms website New Jersey Department of Environmental Protection, HABs in Drinking Water Supply Freshwater Cyanobacterial Harmful Algal Blooms Response Strategy (pdf) Freshwater Cyanobacterial HAB Fact Sheet (pdf) Freshwater CyanoHABs and CyanoToxins: Recreational Exposure and Health Effects Fact Sheet (pdf) Freshwater Cyanobacterial Harmful Algal Blooms Online Reporting Form Marine Harmful Algal Blooms Fact Sheet (pdf) New Jersey Department of Environmental Protection, HAB
New Mexico	New Mexico Environment Department - Harmful Algal Blooms
New York	New York State, Department of Environmental Conservation: HABs Harmful Algal Blooms (HABs) Program Guide
North Carolina	North Carolina Department of Health and Human Services, Blue-Green Algae North Carolina Environmental Quality, Algal Blooms North Carolina Department of Environmental Quality, HABs Monitoring
North Dakota	North Dakota Department of Environmental Quality: HABs North Dakota Game and Fish Department, HABs
Ohio	Ohio Environmental Protection Agency: Algal Toxin Analysis Options (pdf) Ohio Environmental Protection Agency: Algae Information for Public Water Systems Ohio Environmental Protection Agency: Algae Information for Recreational Water
Oklahoma	Oklahoma Department of Environmental Quality: HABs Oklahoma Tourism and Recreation Department Harmful Algal Bloom Oklahoma State Department of Health: Blue Green Algae
Oregon	Oregon Health Authority: Blue-Green Algae Labs and Expert Contacts List Oregon Health Authority, Harmful Algal Bloom Surveillance Program Oregon Health Authority, Algae Resources Oregon Health Authority, Algae Bloom Advisories
Pennsylvania	Pennsylvania Department of Health, Harmful Algal Blooms PA Department of Environmental Protection/Harmful Algal Blooms
Rhode Island	Rhode Island Department of Environmental Management, Cyanobacteria (Blue Green Algae) (freshwaters)
South Carolina	Cyanobacteria: Understanding Blue-Green Algae’s Impact on Our Shared Waterways, South Carolina Waterways, Clemson University South Carolina Department of Health and Environmental Control, Harmful Algal Blooms South Carolina Beach Guide
South Dakota	South Dakota Department of Health, Algal Toxins/Cyanobacterium
Tennessee	Tennessee Department of Environment and Conservation Harmful Algal Blooms
Texas	Texas Parks and Wildlife Department, Harmful Algal Blooms Guide for Public Health Response to Cyanobacterial Harmful Algae in Recreational Freshwater in Texas (pdf) Texas Health and Human Services: Harmful Algal Blooms – Seafood and Aquatic Life
Utah	Utah Department of Environmental Quality HABs Utah Department of Health: HABs Utah Department of Environmental Quality, HAB Map
Vermont	Vermont Department of Health, Cyanobacteria, Blue-Green Algae in Lake Champlain Vermont Department of Health Veterinarian Fact Sheet (pdf) Vermont, HAB Map
Virginia	Virginia Department of Health: HAB Virginia Department of Health: Algal Bloom Surveillance Map
Washington	Washington State Department of Health, Division of Environmental Health, Cyanobacteria (Blue-Green Algae) Washington State Toxic Algae, Freshwater Algae Bloom Monitoring Program Washington State Toxic Algae Online
West Virginia	West Virginia Department of Health and Human Resources, Information on Cyanobacterial Blooms (Blue-green Algae Blooms) or Harmful Algal Blooms West Virginia Department of Health and Human Resources, Harmful Algal Bloom Response Plan for Recreational Waters
Wisconsin	Wisconsin Department of Health Services, Blue-Green Algae Wisconsin Department of Natural Resources Blue-Green Algae website Public Health Madison-Dane County Beaches Wisconsin Department of Natural Resources, Beach Health
Wyoming	Wyoming Department of Environmental Quality, Harmful Cyanobacterial Bloom, Current Advisories

How to use the table.

1. Open your state’s own page first and read its tier definitions next to the status word.
2. Look for the pet line. Oregon puts one in its tier definitions, Kansas in Watch and Warning but not Hazard (where its general animal instruction still applies), Utah in none. If your state’s tiers do not mention animals, the status is a human status.
3. Check whether the number was measured near where your dog will be. If the page names a swimming beach, that is where the sample came from.
4. Note the date on the status.

Freshwater Only

This page stops at the coast because the organisms and toxins differ, and one route has no freshwater equivalent. EPA says one marine HAB, the red tide organism Karenia brevis, can be aerosolized through wave action and has been implicated in respiratory illness from breathing the aerosols. Nothing here about drinking, grooming or shoreline scavenging addresses breathing aerosolized toxin on a beach.

State directories mix the two. In EPA’s directory, Maine’s entry includes a red tide page from its Department of Marine Resources, Delaware’s includes one titled “What is a Red Tide?”, Florida’s includes a red tide current status page, Hawaii’s entries are ciguatera fish poisoning and stinging seaweed disease, and Alabama’s is a coastal beach monitoring program. If you are on the coast, the freshwater guidance here is the wrong guidance, and you want your state’s marine program.

Your Algal Bloom Checklist

Before you go

• Find your state’s own HAB page from the table above, and bookmark the agency page rather than the federal directory entry.
• Read your state’s tier definitions once, on a calm afternoon. Warning is a middle tier in Kansas and California, the lower of two in Utah, and not a tier in Oregon, Wyoming or Idaho.
• Check whether any tier in your state mentions pets. If none does, treat every posted status as a human status.
• Check whether your state publishes a separate animal value. Oregon and Indiana do; EPA’s threshold compilation lists only thresholds it found publicly available.
• Pack water for the animal so the lake is never the drinking source.
• Carry rinse water in addition, enough to rinse a coat, plus soap if your state names it (Indiana, Idaho and Oregon do).
• Put gloves in the car or day pack.

At the water

• Look for scum, foam, mats, discoloration or a bad smell.
• Do not treat clear water as cleared water.
• Keep the animal off the shoreline, not just out of the water.
• Do not let the animal eat anything at the edge. Dried and stranded material is the concentrated form.
• Do not fill a bowl from the lake, and do not try to fix lake water by boiling or filtering.
• Treat a posted advisory as a floor on the danger, not a ceiling, and a lifted or milder status as information about people, not the animal.

If the animal got in

• Rinse immediately, with gloves on, before the animal grooms itself, using water you brought, not the lake.
• Stop the licking. EPA and Indiana both instruct against letting the animal lick material off its fur.
• Call the veterinary practice rather than waiting for symptoms if the animal drank the water or ate or licked scum.
• Say “harmful algal bloom” on the phone, and say when and where.
• Watch for the full window, not the first hour: symptoms can arise anywhere from 15 minutes to several days after exposure.
• File the bloom report and, if the animal is ill, the animal illness report.

For a pond you own

• Assume no agency is monitoring it.
• Fence and re-route before reaching for chemicals.
• Take the treatment question to a veterinarian or your state extension service.

Where to Go Next

This page is one spoke of our pet emergency playbooks hub.

If the hazard is your household’s tap rather than a lake. Pets and a boil water advisory covers the advisory types and which ones boiling fixes or makes worse.

If the animal came out of the water covered in something. Our floodwater washing guide covers getting contaminated water off a coat, the same physical job as the rinse here even though the contaminant differs.

If the water source is out. How long a dog can go without water covers the timeline.

If the trip is on the water. Our dog overboard guide covers recovery for a dog that goes in unexpectedly.

Then spend ten minutes now: open your state’s HAB page from the table, find its tier definitions, and write down whether any tier mentions pets. If none does, you have learned the most useful thing on this page: the sign at your lake is not going to answer your question, and the water you brought is.