San Diego

Algal Blooms That Harm Children and Pets Could Spread Through California's Waterways

A variety of symptoms may develop from exposure to the algal blooms, which are most detrimental to children and pets.

Harmful algal blooms are beginning to spread through California's waterways, covering lakes and rivers with emerald scum just as San Diegans get ready to go swimming this summer.

The State Water Resources Control Board has warned the public to be mindful of this public safety risk. State officials say children and pets should be kept away from certain lakes and reservoirs as the sickly blooms permeate the water.

Algal blooms appear like blue-green algae and are capable of producing unhealthy toxins that can negatively impact people, pets, livestock, wildlife and the environment, said state officials. They are most at risk of being adversely affected because of their small body size and tendency to stay in the water for longer.

Exposure to the bacteria in these algal blooms can cause eye irritation, skin rash, mouth ulcers, vomiting, diarrhea or cold and flu-like symptoms, state officials said.

The bacteria contamination can even prove fatal for some animals. A pet who drinks the algal-poisoned water could develop the aforementioned symptoms as well as abnormal liver function, difficulty breathing, foaming at the mouth, muscle twitching and even death, according to the state water board.

The primary toxins in the algal blooms are small microbes known as cyanobacteria. Cyanobacteria toxins can be poisoning local lakes or rivers even when a blue-green bloom is not visible in the water, warn state officials. The algal blooms can vary in color and hues from vibrant emerald to dark green to turquoise blue-green to yellowish, dirt brown, charcoal black or even red.

Sometimes the algal blooms float on the water's surface, but at other times it will stick to the bottom of a waterbody or float at various depths, said state officials. 

Fore more information on reporting a bloom and tracking multiple blooms across the state, visit the California Harmful Algal Blooms Portal here. There is also a Bloom Watch smartphone app that allows you to get familiar with the appearance of cyanobacteria blooms.

So far, no harmful blooms appear to have affected San Diego but you can check the portal regularly for updates.

Some tips from the state water board to prevent harmful algal blooms include the following:

  • Be careful about using water, fertilizers and pesticides on your lawn and garden.
  • Recycle any "spent" soil that has been used for intensive growing by reusing it in gardens to avoid nutrient runoff.
  • Create shade and filter out nutrients by planting native plants around river banks.
  • Inspect and pump out septic systems every three to four years.
  • Find ways to prevent surface water runoff and erosion around construction areas.

The state board made these recommendations to stay safe:

  • Keep pets out of the water and do not allow them to drink water or eat algal scum on the shore.
  • Don't drink, cook or wash dishes with untreated water.
  • Understand that even common water purification techniques such as camping filters, tablets and boiling will not remove algal bloom toxins.
  • Don't eat mussels or bivalves taken from algal bloom-affected areas.
  • Avoid eating fish from these areas. If you must eat fish, remove the guts and liver, and rinse the filets in clean drinking water.
  • If anyone thinks they may gotten sick from exposure to algal blooms, state officials say you should get medical help immediately.
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