Owners strongly advised to keep pets out of Lady Bird Lake.
The City of Austin is advising pet owners to not allow pets to swim in or drink water from Lady Bird Lake after being notified that two dogs have died after swimming in the lake. The City cannot confirm the cause of either death.
On Sunday, City of Austin scientists investigating the water quality noted the presence of clumps of algae in Lady Bird Lake. Preliminary results indicate the algae is a type of blue green algae of the genus Oscillatoria. This type of algae can release a neurotoxin. The neurotoxin in this type of algae can be harmful to pets and people if a sufficient quantity of water or algae is ingested.
The algae is especially prevalent near Red Bud Isle, covering up to 40% of the water surface in that area. It also tends to be more abundant near shorelines and in areas with low water flow. The situation is evolving. We have not seen any impacts to aquatic species at this time.
There have been blue-green algae blooms in Austin in previous years, but we have not been aware of any effects from neurotoxins. Algae tends to be more prevalent in late summer and early fall and when flows are low.
Austin Water regularly looks at algae levels on Lake Austin and Lake Travis and has not seen levels of concern for drinking water. Austin Water does not use Lady Bird Lake as a source for drinking water.
The current algae bloom appears to be confined to algae growing on the bottom of the lake and then floating in clumps to the surface. Scientists have taken samples of both the algae and the water near the algae in Lady Bird Lake. Results from the analysis for the actual presence of the toxin should be available early next week.
Dogs who ingest water contaminated with this toxin could have a number of symptoms. On the severe end, it could result in respiratory paralysis and death. Look for these signs in your pet within minutes to hours of exposure:
Excessive drooling, vomiting, diarrhea
Foaming at the mouth
Blood in urine or dark urine
Loss of appetite
Photosensitization in recovering animals
Progression of muscle twitches
Until we have more information, we strongly advise that pets stay out of the water. At this time, we have no reason to believe that boating is unsafe. However, people should not be swimming in Lady Bird Lake. It is illegal. When out on the lake, people should take care to avoid ingesting water or coming into direct contact with the algae. The degree of risk to human exposure, such as through accidental swallowing of lake water, cannot be known until the tests results are available and analyzed.