San José, Costa Rica, since 1956

Mudslides Threaten Escazú

EMERGENCY officials in Escazú, west of SanJosé, are warning residents and hikers in the protectedhills above the town that more big mudslides arepossible during the next few weeks.Approximately 15,000 square meters of mud,rock and debris slid down a protected mountainousarea between Cerro San Miguel and Pico Blanco earlierthis month, and officials are warning it couldhappen again soon.Geologist Julio Madrigal, of the NationalEmergency Commission (CNE), estimated thatbefore the rainy season is over, likely sometime nextmonth, another 15,000 square meters of mud willslide off the mountain and wash down the AgresRiver, which runs through the communities of SanAntonio and San Rafael de Escazú.THE area surrounding the banks of the AgresRiver has been under yellow alert since Oct. 12 andwill likely remain so until sometime in November,when the transition period between the rainy and dryseasons begins in the Central Valley, according to theNational Meteorological Institute.Emergency commission spokesman JorgeAlvarez said the yellow alert is issued for possiblydangerous situations that can be predicted, such ashurricanes or heavy rainfall. It tells local emergencycommittees to communicate the danger to the communityand prepare accordingly.Catalina Roldán, assistant to the Escazú Mayorand member of the Escazú Emergency Committee,said, “landslides like this happen all the time, but thedanger here resides in the Agres River. It flows rightunderneath the land that is waiting to fall, and could drag it down to populated areas.”Fortunately, she said the immediatevicinity of the land expected to tumbledown is a protected area and thereforeuninhabited.Roldán predicted a range of consequencesif the landslides continue. She saidafter the land crumbles or slides into theriver, the waterway could grow and flood asit often does during the rainy season.However, “in the worst of cases, thelandslide could form a natural dam thatwould accumulate water into a lagoonuntil it finally bursts in an avalanche oftrees and rocks,” she warned.SHE said this is likely what happenedin October 1861. Although no officialrecord exists, she said studies of the Agresand testimonial records passed downthrough generations of Escazú residents byword of mouth indicate there was anavalanche around that time, which scatteredhuge boulders around Escazú stillseen today in backyards and parks.“That avalanche did not yield deadlyconsequences because Escazú was not asdeveloped in 1861 as it is today,” Roldánsaid.It was in October 2003 that a hikingguide on a recreational walk first reported tothe Escazú Municipality what appeared tobe a large crack on the side of Pico Blanco.A geologist and an engineer visited the siteshortly after, and since then the emergencycommittee has taken a series of preventivemeasures in case of a major slide.THE Escazú Emergency Committeeincludes government officials, Red Crossvolunteers and interested members of thecommunity.In June, the committee distributed anofficial bulletin to homes near the Agres,requesting their registration with the committeeand their help evaluating the obstaclesalong the river.The bulletin listed 12 danger pointsalong the Agres, in order of their proximityto the potential mudslide. It starts withthe National Water and Sewer Service(AA) sand-clearing station on theriverbed, and continues with the entranceto the protected area of the Escazú hills atLos Filtros, Los Delgado Street, SanAntonio Street, Badilla lots in SantaTeresa, Los Reyes Street, Voyogres, theGiacomin Café street, Málaga street, andfinally, Plaza Colonial Street.Roldán said the emergency committeehas contacted almost 90% of the residentsof these at-risk areas. The committee hasorganized monthly meetings with leadersfrom Escazú communities who are incharge of informing their neighborhoodsand divulging safety procedures to followin case of a slide.THE committee also closely monitorsthe slide area. Roldán and engineer MichelleArias, along with other committee members,visit the site approximately twice aweek, or after each heavy rainfall.Roldán told The Tico Times thisweek the river “is behaving very well.The river floor has ascended and turnedswampy, so the water is flowing unobstructed.No lagoon has been formedafter the landslide on Oct. 12, when theland slid some 500 meters downhill.”Madrigal, of the National EmergencyCommission, says the land has been slidingoff in portions and “the situation is notcritical.” He says San Antonio is the closesttown to the landslide area and it is still“quite far.” San Antonio is approximately4.5 km from the landslide.He said the yellow alert is necessarybecause people sometimes do not want topay attention to the possibility of danger.Those who live near the Agres should beaware that heavy rain, a sudden, considerablechange in the size of the river, or a shiftin its color from chocolaty brown to clear,may be signs of water blockage upstreamand could announce a coming avalanche.Residents should evacuate the area.For emergency assistance, call: 911,the Escazú committee at 228-7762, theCNE at 220-3588, or the EscazúMunicipality at 228-5757, ext. 218.

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