End of the Green Water? Sant Elm Tests Seawater Recirculation

A technical attempt against the green water

Early in the morning at 8:15, at the kiosk on Plaça in Sant Elm, you can see it for years: the sea sometimes looks as if someone had thrown green patches into it. The municipality of Andratx has had enough and now has made a clear statement—not with beach bans, but with technology.

What exactly is happening?

On the shore, a stationary seawater recirculation system has been installed: three powerful pumps, pipelines and diffusers intended to move the coastal water. The installation costs about 350,000 euros, according to the town hall. The systems operate in the season; in winter the pumps are dismantled again, explain the responsible authorities.

The plan is simple in concept, complicated in implementation: through better mixing, the accumulation of nutrients and thus the massive bloom of algae shall be reduced. Anyone who swims here often knows the green veils that in some years spoil the fun—and occasionally bother fishermen and deck chair renters.

Who is behind it?

The environmental council Antoni Nicolau explains that they invested time in planning and coordination with marine biologists and other authorities. Mayor Estefania Gonzalvo emphasizes that the measure is an example that problems are not just commented on, but tackled. I heard two locals at the bakery on the corner say snarkily: \"Let’s see if the pump works better than the wind.\"

The technology is not new, but here they want to test it over the longer term. From 2026—so the official hope—first visible improvements should be detectable. Until then, patience is required: marine ecosystems do not respond overnight.

What does this mean for tourists and residents?

For vacationers this means: fewer annoying green patches in the water, more pleasant swimming, and bays that look cleaner. For the neighborhood, it means investments in a place that gets quite crowded in summer but remains quiet outside the main season. And those looking from here to the uninhabited island Sa Dragonera still see the rugged silhouette with its many lizards—unchanged.

Whether the facility will achieve the intended result remains to be seen—through measurements, by visual observation, and by the small but important verdict of the people who come daily to the beach here. I, for one, will stand again early next summer on the promenade by the shore — coffee in hand, looking at the sea — and see if the water looks bluer.