Volcán Poás on Orange Alert: Increased Activity and Preventive Measures (Update – March 31, 2025)

I. Headline and Executive Summary

Headline: CNE Raises Alert to Orange at Poás Volcano Following Significant Increase in Eruptive Activity
Summary: The National Commission for Risk Prevention and Emergency Response (CNE) has declared an ORANGE ALERT for the Poás Volcano National Park and the Toro Amarillo district of Sarchí canton, including the Desagüe and Agrio river basins. This decision, announced on March 31, 2025, at 2:30 p.m., responds to a sustained increase in volcanic activity reported by experts.

II. Context and Background

The Poás Volcano, known for its intermittent activity, has been under constant monitoring by the Technical Advisory Committee (CAT) on Volcanology and Seismology, composed of the Volcanological and Seismological Observatory of Costa Rica (OVSICORI-UNA), the National Seismological Network (RSN – ICE-UCR), and the Atmospheric Chemistry Laboratory (LAQAT-UNA) of UNA, in coordination with SINAC-MINAE authorities.

Previously, the volcano was under a yellow alert status. The elevation to orange indicates a higher level of risk due to the intensification of its activity.

III. Reasons for the Change to Orange Alert (According to the CNE Report)

In recent hours, experts have reported a notable increase in activity at Poás Volcano, including the following aspects:

Continuous Emission of Ash and Gases: The volcano is releasing significant amounts of ash and gases.
Energetic Eruptions: During the weekend prior to March 31, very energetic eruptions were recorded, some frequently exceeding the height of the crater.
Nearly Continuous Low-Amplitude Eruption: A nearly continuous, though low-amplitude, eruption is being observed.
Seismic Activity, Ground Deformation, and Other Variables: Seismic activity near the volcano, ground deformation, and other variables typical of an active volcano in an eruptive phase continue to be present.

IV. Affected Areas and Alert Levels (According to CNE)

ORANGE ALERT:

Poás Volcano National Park (with increased safety measures).
Toro Amarillo District of Sarchí Canton (including the Desagüe and Agrio river basins).

GREEN ALERT (Remains in place for the following cantons):

Alajuela
Poás
Grecia
Sarchí (except Toro Amarillo District)
Naranjo
Río Cuarto
Zarcero

V. Measures and Recommendations from the CNE

In light of the increased volcanic activity, the CNE requests that institutions, emergency committees, and the general public implement the following measures:

A. Increase safety measures within Poás Volcano National Park: Due to ash, gas, and other material emissions, there is a risk to life.
B. Use only official primary sources of information: It is recommended to consult reports from OVSICORI, RSN, or CNE to obtain accurate and up-to-date information.
C. Maintain constant communication with municipal and community emergency committees: This is crucial for reporting ashfall or the presence of volcanic gases in communities.
D. Keep high-risk areas active and under surveillance: The cantons surrounding the national park must be prepared for the possibility of a major eruptive event.
E. Review available resource inventories: Emergency Committees must ensure the availability of resources to assist people who may be affected.
F. Follow the recommendations of park rangers and relevant authorities: The general population is reminded not to enter unauthorized areas that pose a high risk to life.

VI. Outlook and Monitoring

The activity of Poás Volcano continues to be closely monitored by CAT experts. The CNE remains attentive to the evolution of the situation and will issue new updates as necessary.

VII. Conclusion

The declaration of an Orange Alert at Poás Volcano underscores the importance of constant monitoring and the adoption of preventive measures. The CNE urges the population to stay informed through official channels and to strictly follow the recommendations of authorities to ensure safety in potentially affected areas.