The national emergency commission has identified eight slopes that are in danger of becoming landslides in the Central Valley.
Two are in Santa Ana, one is in Escazú and one is in Mora near Ciudad Colón. Others are in Alajuelita, Desamparados, Acosta and Aserrí.
None comes as a surprise because they have been trouble spots in the past. The commission said that about 100 families are in danger because of these potential landslides.
The largest is in Acosta at the Ortiga-Porterillos slope where 122 hectares (about 300 acres) are unstable, according to the commission.
The commission held a meeting Tuesday with municipal officials and others to set up a monitoring system for the mountains that may cause slides.
In addition to identifying families at risk, the commission will provide air surveillance of the locations and place instruments on the slopes to detect movement. An alert system also will be put in place.
Last November, heavy rains spawned by then-Tropical Storm Tomas caused part of Pico Blanco above Escazú to slide. The death toll was 23 at Calle Lajas in San Antonio de Escazú where houses were buried. The central government has since ordered the evacuation of the remaining homes below the slope.
The municipalities Tuesday agreed to take some preventative measures such as cleaning waterways, removing sediment, cutting trees that might interfere with the water flow and making contact with families in high-risk areas.
Those involved in the session will be visiting the Tablazo slide site in Desamparados today. Thursday they will be at the Burío site in Aserrí. In addition to Tablazo, Burío and Pico Blanco, officials also have their eye on Tapezco, Pacacua and La Cascabela as potential slides.
Much of the land area is unstable and is easily moved by heavy penetration of rain water.
Both Tapezco and Chitaría peaks are in Santa Ana in the district of Salitral, which also suffered heavy damage last year. Pacacua is in the Cantón de Mora and is less than a hectare in area. Also small is the La Cascabela site in Alajuelita in San Felipe.
Caribbean hurricanes and tropical storms dump feet of water on Costa Rica and provoke land movement. Typically roads are blocked, and vulnerable towns are flooded.
There have been slides in the past that have caused multiple fatalities. The Atlantic hurricane season started June 1.
The eastern Pacific has its first tropical storm of the season, Tropical Storm Adrian. It is west of southern México.