Blue-green algae
When it is very warm, blue-green algae can develop. Humans and animals can become ill if they come into contact with it. Before you go swimming, check zwemwater.nl.
What are blue-green algae?
Blue-green algae are bacteria that look like algae. They are toxic. These bacteria are always present in natural water. In the warmer months, they can cause a lot of nuisance. At higher temperatures, blue-green algae can bloom. Blue-green layers form and float on the water like oil. When the blue-green algae die, they can start to smell and release toxins into the water. These toxins can cause serious health problems in humans and animals.
Blue-green algae and lake Paterswoldsemeer
The sun is shining and the temperature is rising. What could be nicer than cooling off in the water? But sometimes blue-green algae can spoil the fun. What exactly is the situation with blue-green algae in lake Paterswoldsemeer? Find out in less than 4 minutes!
Warning signs
In areas where blue-green algae have been detected, the water authority attempts to improve the quality of the surface water by supplying additional water. Where possible, we separate contaminated water from other water sources. Blue-green algae usually disappear as soon as the weather becomes cooler.

What should you do if you come into contact with blue-green algae?
- Have you been in contact with blue-green algae? If so, rinse yourself thoroughly in the shower. Blue-green algae that die and dry on the skin can cause skin and eye irritation.
- Have you ingested water containing blue-green algae? If so, you may experience symptoms such as fever, nausea, abdominal cramps, diarrhea, and vomiting.
- If you have any symptoms, always see your doctor. Do not allow your pets to swim in or drink from the water. We advise you to only swim at official swimming spots. The water in these swimming spots is checked regularly for bacteria such as blue-green algae.
- Before you go swimming, check zwemwater.nl.
Difficult to deal with
It is difficult to combat blue-green algae. Many factors play a role: location, wind, soil layers, amount of nutrients in the water, flow, depth, temperature. We are learning more and more about blue-green algae. Unfortunately, there is still no solution for effectively removing all blue-green algae.
Blue-green algae is a global problem. The problem is expected to get worse. This is because the earth is warming up and there are more nutrients in surface water, which blue-green algae thrive on. We are keeping a close eye on the latest methods for dealing with blue-green algae. We are looking for a method that is not harmful to other plants and animals in the water. That is why we cannot just try anything.
Algae sensor
An algae sensor enables us to better predict and combat blue-green algae. The sensor continuously records the colour and clarity of the water. This "Ecowatch" sensor quickly shows us where algae are present in the lake and how they are moving or spreading. This offers several advantages:
- Swimming spots need to be closed less often due to blue-green algae. With the sensor, we know sooner when blue-green algae disappear from swimming spots. We don't have to wait for laboratory tests of the water.
- We can better advise managers of swimming spots on measures to prevent and potentially combat blue-green algae.
- We can improve the design of areas to help prevent blue-green algae.
Sensor lake Paterswoldsemeer and lake Lauwersmeer
- In summer, lake Paterswoldsemeer often suffers from algae growth, such as blue-green algae. This causes problems for many swimmers, water sports enthusiasts, residents, and others who want to enjoy the lake. For example, when swimming is advised against or prohibited due to blue-green algae. This algae sensor is proving very effective. That is why we will be using the sensor in lake Lauwersmeer from the coming 2021 swimming season, most likely at De Meerkoet beach.