In some of these sites, a common practice for builders is making cuts in the land and the use of poorly compacted soil fill
added to poor water sewage systems, which increases the chances of large landslides - National Emergency Commission photo -

Published Tuesday, October 6, 2020

More than 130 landslides reported
during the green season

By the A.M. Costa Rica staff

Increased rainfall, earthquakes and topography shifts of some zones, and landslides are becoming more common during the green raining season.

The National Emergency Commission reported on Monday the record of at least 135 large landslides in the country.

Most of these landslides are in urban areas in the Greater Metropolitan Area, GAM. This area is made up of cities in the outskirts of San José such as Alajuela, Heredia and Cartago.

Other large-scale landslides were reported in the Cantons of Turrialba and Los Santos in Cartago Province, Pérez Zeledón in San José Province, Tilarán in Guanacaste Province, Quepos, Corredores, Coto Brus, and Golfito in Puntarenas Province, among others.

"In Costa Rica, at least 60% of its territory may be vulnerable to landslides that are accelerated by factors such as geological composition, slope, earthquakes, and climatic condition," Lidier Esquivel, geologist of the Commission said. "We must also add human factors such as poor sewage water structures or construction on dangerous grounds, among others."

Although a landslide can happen anywhere, there are areas that, due to their characteristics, present a greater probability of avalanches, such as some sectors of Desamparados, Acosta, Puriscal or Pérez Zeledón in San José Province, as well as Los Santos in Cartago Province, the Commission said in its statement.

In some of these sites, a common practice for builders is making cuts in the land and the use of poorly compacted soil fill added to poor water sewage systems, which increases the chances of large landslides, Esquivel said.

One of the most recent larger landslides was reported last week in the
Valladolid community in Desamparados Canton, San José Province.

Thirty-four families living in Valladolid were evacuated by officials from the Municipality's emergency committee due to a large-scale landslide.

Officials from the National Emergency Commission observed the condition of the landslide and its impact on the community's houses.

According to the Commission, this landslide was initiated in 2017 after the passage of Tropical Storm Nate, and as a result of the recent rains, landslides have been registered, as well as breaks in houses.

Historically, emergencies have been attended due to large landslides, such as in 2010 in the Lajas community in Escazú Canton where a landslide was caused by Tropical Storm Tomas.

On the night of November 3, 2010, after 72 hours of continuous downpours generated by the direct impact of Hurricane Thomas, a landslide fell from Cerro Pico Blanco directly over the community of Lajas. There were 32 families who lost their homes and 24 people dead. Thereafter, the community was declared uninhabitable by the Commission.

Experts warn of signals that happen before a large landslide, such as windows breaking, walls showing cracks, the inclination of trees or electric lines poles, breaking of water pipes and sewers, among others.

On any of those signals, experts advise reporting the risk that a landslide could occur to the municipality, then experts can analyze the place and safeguard the people living in that zone.

Regarding the increase in rains, the Commission declared an Orange alert in the northern zone of the province of Alajuela and the province of Guanacaste. Also, the authorities maintain the Yellow alert in the province of San José and the Pacific Coast (Province of Puntarenas). The rest of the country remains on Green Alert.

Specialists from the National Emergency Commission recommend that people consider the following safety measures:

• Keep the roof of your house clean.

• Clear a path in the backyard allowing rainwater to move without problems towards the drainage, which helps to avoid damages and leaks in the house.

• Pick up the garbage so that it does not fall on the pipes or drains on the sidewalks.

• Avoid that solvents, oils, acids or corrosive liquids that can fall into the sewer pipes and deteriorate them.

• Organize the cleaning of public areas such as river banks in your community to avoid flooding.

• Report the lack of concrete caps or grids in the pipes to the Aqueduct Institute by calling 2547-6555.

Authorities call on the public to take the following precautionary measures:

• Stay informed about the alerts issued by the authorities.

• People living in mountain areas should increase precautionary measures against a possible landslide or material falling from the high areas of the hills.

• Have an emergency evacuation plan in the community, work and home.

• Drivers must increase precautions for heavy rain and fog.

• Take precautionary measures in case of electrical storms.

• Be alert in vulnerable areas to flooding due to sewer saturation or increase of river flow.

• In case of a thunderstorm, take refuge in a safe place.

• In case of strong wind gusts, be alert to possible falling tree branches or electrical cables.

• In the event of a landslide, do not walk on the debris, stay away from affected areas, and do not return home until authorities verify that it is a safe place.

Authorities ask for the people in Costa Rica to call 911 to report any possible flooding, fallen trees or landslides.

A.M. Costa Rica urges readers to share this alert with their contacts.

What emergencies have you heard caused by landslides in your community? We would like to know your thoughts on this story. Send your comments to