What is blue algae and is it dangerous?

In the summer, it sometimes pops up in the news: blue algae. It may sound harmless, but this water bacteria does pose risks for humans and animals. In this article, we'll explain exactly what blue algae is, how it occurs, where it can occur, but above all: why you can sleep soundly so that you won't end up in blue algae while bobbing. ;-)

What exactly is blue algae?

Blue algae, also known as cyanobacteria, is actually not an algae, but a bacteria that lives in stagnant or slow-flowing water.

At warm temperatures and an abundance of nutrients such as phosphates and nitrates in the water, blue algae can multiply rapidly and cause a so-called “bloom”. Then you see a blue-green, oily or foamy layer on the surface of the water, whichever the name comes from. Some types of blue algae can also cause odour nuisance.

Where does blue algae occur in Flanders and the Netherlands?

Blue algae mainly occurs in stagnant water such as ponds, canals, recreational lakes and slow-flowing rivers. In Flanders, it has occurred in recent years, among others, on the Ster in Sint-Niklaas, the Donkmeer in Berlare, and the Schulensmeer in Lummen.

It is also occasionally banned in the Netherlands, for example the Binnenschelde near Bergen-Op-Zoom, the South-Willemsvaart and the Hitsertse Kade have been closed to swimmers in recent years.

The risk of blue algae is highest in hot and very dry summers where there is little water change. It is therefore a very rare phenomenon in our parts, although the number of prolonged heat waves has been increasing in recent decades.

What are the risks of blue algae?

At a high concentration, blue algae can secrete toxic substances (toxins) that are harmful to people and animals. A number of possible health complaints include: skin irritation, headache, nausea or vomiting, diarrhea and eye or throat irritation.

But dogs in particular are extra vulnerable: they like to play in the water, and therefore drink contaminated water rather quickly or lick their wet coat clean after taking a dive.

Video: a brief explanation of blue algae

What does the government do about blue algae?

The Flemish government and local authorities monitor water quality through regular checks. When blue-green algae bloom, warning signs are placed and swimming or contact with the water is prohibited.

Where can you find information about blue algae infections?

Through websites such as www.kwaliteitzwemwater.be and https://www.vlaamsewaterweg.be/nieuws/blauwalgen-actueel you can find all the latest information about open-air bathing waters. For the Netherlands, you can then go to https://www.zwemwater.nl/ for a current state of affairs.

So you can also find our kayak locations on these websites.

What can you do yourself to never be surprised by blue algae?

• Check before you go whether there are reports of blue algae at your destination via government websites. And then just stay out of there, because you really won't be allowed into the water.
  
  
• General tip: don't let your dog swim or drink either from suspicious water.
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• Wash your skin good off if you may have come into contact with potentially bad water.

And what about kayaking or supping with blue algae?

At Dobber, we closely follow government advice on water quality and swimming. If there is blue algae and there is a real health risk, we take appropriate measures. This can range from temporarily closing one or more routes to - if necessary - completely closing the locker at that location.

We are in direct contact with the competent authorities and are notified by them when action is needed.

We proactively inform everyone if a location is temporarily inaccessible due to blue algae. Did you already make a reservation and are you unable to go because of this? Then, in case of cancellation, you will definitely receive a voucher that allows you to come and float at a later date or at a different location!

So blue-green algae doesn't have to put a damper on your summer at all. The necessary authorities do everything to ensure that you enjoy water fun without worries. Reserve a SUP or kayak with Dobber and have an unforgettable day on the water!

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