From Cancún to Mahahual, sargassum influx puts nearly 50% of Riviera Maya beaches on red alert

May 29, 2026

Dozens of sargassum collection workers clean a large Playa del Carmen beach covered in sargassum seaweed — Workers clear sargassum from a beach in the resort town of Playa del Carmen, where cleanup crews struggled to keep up with the volume of seaweed washing ashore this week. (Elizabeth Ruiz / Cuartoscuro.com)

Nearly half of Quintana Roo beaches are currently on red alert due to a massive influx of sargassum seaweed in recent days, making conditions unsuitable for swimming or enjoying the otherwise turquoise waters.

Head of the Sargassum Monitoring Center in Quintana Roo Esteban Amaro reported that substantial amounts of seaweed accumulating offshore triggered the alert in 65 of the 140 beaches monitored in the state.

A colorized satellite image from the National Earth Observation Laboratory (LANOT) at UNAM shows sargassum on and near shore in Quintana Roo — A colorized satellite image from the National Earth Observation Laboratory (LANOT) at UNAM shows sargassum on and near shore May 20 in northern Quintana Roo (at left) and the southern part of the state (at right). (LANOT)

“We have observed a significant increase in the amount of sargassum in the first five nautical miles off the coast in the state of Quintana Roo,” he said.

There are 34 beaches on red alert in the northern part of the state, Amaro said, including numerous beaches in Cancún, Playa del Carmen and Tulum. In southern Quintana Roo, there are 31 beaches on red alert, mainly in and near Mahahual, another popular tourist destination.

Forecasts indicate sargassum will continue to increase on the Riviera Maya’s shores. According to monitoring reports, the first week of June will see larger quantities of sargassum wash ashore in both the northern and southern parts of the state, partly due to intensifying strong winds coming from the southeast.

The amount of sargassum has overwhelmed local business owners, who said it has exceeded the capacity of cleaning brigades.

A sargassum collection workers shovels seaweed in Playa del Carmen on Tuesday. (Elizabeth Ruiz / Cuartoscuro.com)

Earlier this month, the Navy announced the deployment of an additional 150 personnel to support the cleaning and containment efforts of the seaweed before it reaches the shores of Quintana Roo. Furthermore, authorities added a new sargassum collection vessel that can collect up to 600 tons daily on the high seas, compared to the 250 tons that were previously collected.

But collection efforts don’t come without risks for workers. A new study conducted by the National Autonomous University of Mexico (UNAM) found that workers who collected sargassum on beaches in Puerto Morelos, Playa del Carmen and Mahahual suffered headaches, rashes, nausea, difficulty breathing and other health issues after exposure to the hydrogen sulfide that is released by the algae as it decomposes.

With reports from La Jornada and El Economista