South Holland is rich in water. Many lakes, ponds, or coastal areas are suitable for swimming. The province designates official swimming locations every year. In 2025, there are 105 of them. Check the swimming water locations in South Holland for 2025.

Control of Official Swimming Locations

The water quality, hygiene, and safety of an official swimming location are checked during the swimming season (May 1 to October 1). All locations are examined at least once a month. Locations rated with acceptable or poor swimming water quality are assessed every 2 weeks. These checks are based on European regulations. In case of poor water quality, caused by blue-green algae or fecal bacteria, a warning follows or a negative swimming advice is issued. Information about the current situation per swimming location is shared on www.zwemwater.nl (opens in a new window).

Removed and New Swimming Locations

The number of official swimming locations is the same as that of the swimming season 2024. However, one location has been removed from the list, and one location has been added:

• Water playground Cronesteijn in Leiden is no longer an official swimming location. The water quality has been rated poor for 5 years in a row, caused by excessive fecal bacteria from bird droppings. Years of efforts to improve water quality have not yielded sufficient results.
• Location Den Bommel, Badstrand on Goeree-Overflakkee has been designated as an official swimming location for the first time this year.

Negative Swimming Advice

The negative swimming advice that was in effect as a precaution since October 1, 2024, for Plas Merwelanden in Dordrecht will be lifted on May 1, 2025. The flushing of the pond results in PFAS levels well below the advisory value of the RIVM, allowing for safe swimming.

For 2 locations, negative swimming advice still applies due to PFAS contamination.

• Plas Vrijenburgbos in Rotterdam
• Kralinger Esch in Rotterdam

Finally, it is prohibited to recreate in the Valkenburgse Meer. Here, a emergency regulation (opens in a new window) is in effect. Read here about the developments regarding the Valkenburgse Meer.

Want to know more about safe swimming?

• Visit zwemwater.nl
• Download the app from Google Playstore (opens in a new window) or Apple Store (opens in a new window)
• News article from Omgevingsdienst Midden-Holland