We are massively looking to cool down and a dip in the open water is an attractive option, especially next week. But watch out! Blue-green algae is teeming in more and more places. There are now warning signs on many North Holland freshwater beaches. One municipality bravely resists the blue-green ghost: Hollands Kroon. There they are experimenting with a refreshment system in a closed basin. And that works, the basin at Lutje beach is almost blue-green algae free.
The basin has now been in existence for almost a year and is a project that the municipality has set up together with the water board and a number of entrepreneurs. At one time, as many as 900 units of blue-green algae were measured in the water, says Henno Tacx of the Lutje-strand project group. When you realize that the safe swimming limit is 75 units, that means the pool was completely useless. That was the reason for the municipality to start the experiment.
It works (almost)
The water in the basin is constantly refreshed with a pump installation that pumps clean and cool water from the deeper Amstelmeer. This has resulted in much less blue-green algae pollution. The limit value of 75 units is unfortunately not yet reached. Therefore, even for the basin, a negative bathing advice still applies.
The research will continue and experiments will be conducted with the times at which the pumps run. This should ultimately lead to the necessary improvement. When asked whether it is safe to swim in the Lutje-strand basin next year, Tacx cautiously says: “that is the aim, unfortunately it is no longer possible this week”.
Incidentally, the negative swimming advice does not mean that swimming is not allowed in the Lutje-strand basin. “It’s not forbidden,” says Henno Tacx. “It remains the responsibility of the swimmer himself. We cannot enforce it, but it is not wise”.