Update, August 31: The excursion guide swept away in this incident was found dead Sunday evening. The Red Cross confirmed he was the only person reported missing, and everyone else in the group was brought out.
A sudden surge of water swept two people down a river in Barú de Pérez Zeledón on Sunday afternoon, and about 40 others who were crossing with them were brought out over the following hours. The Costa Rican Red Cross said the group was in the middle of a guided excursion when rain upstream sent a cabeza de agua — a wall of water that arrives without warning — down the channel. Two members of the group were carried away. One of them was the excursion’s guide.
The rest of the group was split by the surge. Some were stranded on the far bank with no safe way back across. “The group is divided and several people remain on the other side of the river, unable to leave the site given current conditions,” the Red Cross said.
Two basic life support units are working the scene. The Red Cross has also sent a first-response unit from its National Emergency Response Directorate, along with specialists from its urban search and rescue team and its water rescue team. As of mid-afternoon, neither the condition of the two people swept away nor the status of those still stranded had been confirmed.
What a cabeza de agua actually does
If you are near a river anywhere on the South Pacific slope this afternoon, this is the thing to understand: the water that kills you falls somewhere you cannot see. A cabeza de agua forms when heavy rain lands high in a watershed and funnels into a narrow channel. It travels downstream as a single front.
The sky above you can be bright and the river can be ankle-deep, and the surge still arrives — often in under a minute, and often carrying rock and timber. That is why river levels are the wrong thing to check. What matters is what the clouds are doing in the mountains behind you, and Costa Rica’s terrain means those mountains are frequently out of sight.
Do not cross a river that is rising, or that has turned brown, or that has started to carry debris. If you hear a low rumble from upstream, move away from the channel and uphill immediately rather than trying to finish the crossing. Once a surge is visible it is already too late to outrun it.
The involvement of a professional guide here matters. Guides in this corridor cross these rivers routinely and know the conditions better than any visitor will. When a surge takes the guide, it is a signal that the water moved beyond what experience could read.
Today’s forecast pointed straight at this
The National Meteorological Institute (IMN) forecast strong afternoon downpours with thunderstorms across the Central and South Pacific on Sunday, with the possibility of those conditions running into the early evening. Tropical wave 38 left the country on Saturday, but the instability behind it did not. Morning trade winds kept pushing moisture toward the Caribbean and the Northern Zone, and the IMN warned the atmosphere over the country remained unsettled.
The National Emergency Commission (CNE) has kept its alerts in force. Soils across the Northern Zone and the Caribbean are still saturated after weeks of rain, which means smaller amounts of rainfall now run straight off the ground instead of soaking in. Nine cantons remain under the national emergency decree signed on August 20.
Not the first time
Barú is a district of about 2,400 residents spread across 191 square kilometers (74 square miles) on the Pacific side of Pérez Zeledón. It is also the district that contains Nauyaca Falls, one of the most visited waterfalls in the southern zone. In June, a 30-year-old American visitor, Ashley Phillips, was swept away by a cabeza de agua at Nauyaca. The Red Cross recovered her body 11 days later, roughly 600 meters (1,970 feet) from where she disappeared.
The corridor between Dominical, Uvita and Barú draws heavy visitor traffic during the green season, and its rivers drain steep ground that receives far more rain than the coast below. Anyone booked on a river hike, canyoning trip or waterfall tour in the southern Pacific over the coming days should confirm with the operator that conditions have been checked that morning and should treat a cancellation as the system working rather than as an inconvenience.
This story is developing and will be updated.
