The National Commission for Risk Prevention and Emergency Response (CNE) has raised the alert level to yellow for districts surrounding the Rincón de la Vieja volcano, following determinations by technical and scientific authorities specializing in volcanology regarding an increase in eruptive activity, gas emissions, and seismicity.
CNE President Alejandro Picado stated that the institution made the decision following technical monitoring of the volcanic activity, which has shown a sustained increase since July and registered a sharp surge over the past week.
The yellow alert covers the districts of Dos Ríos and Aguas Claras in Upala, as well as Mayorga, Cañas Dulces, and Curubandé in Liberia. The CNE reminded the public that Rincón de la Vieja is one of the country’s most active volcanoes, prompting authorities to maintain preventive measures in nearby communities.
The Volcanological and Seismological Observatory of Costa Rica (OVSICORI-UNA) indicated in its update that it is observing an increase in various activity indicators, including a swarm of distal and proximal volcano-tectonic earthquakes, episodes of banded tremor, summit inflation, and changes in gas composition involving higher sulfur dioxide levels.
According to the technical report, the volcano recorded multiple eruptions, dominated by acoustic pulses associated with minor steam and volcanic gas explosions. The observatory noted that geophysical and geochemical signals suggest further eruptions could occur, potentially larger than those recorded so far. Despite this behavior, OVSICORI maintains the volcano’s activity level at 3, “Caution,” and continues monitoring through seismic, acoustic, geodetic, and gas stations, as well as surveillance cameras and field observations.
Picado assured that the CNE has trained nearby communities in emergency plans, evacuation routes, shelter management, and safe zones, while also strengthening local emergency committees. The institution has installed warning signs along major river channels on the northern slope to inform residents of potential hazards.
Authorities urged individuals to protect their respiratory tracts in the event of ashfall and to avoid exposure if volcanic material descends through nearby river channels. Residents were also advised not to consume, touch, or supply this water to farm animals.
