From the print edition
Driving north out of San José on one of the country’s most important highways, the road suddenly narrows and steel trusses appear on both sides of the asphalt and down the center of the street. Two Bailey bridges were opened on General Cañas Highway on Tuesday, after a large sinkhole opened up on the route last week.
The Roadway Safety Council (CONAVI) backtracked on earlier estimates that repairing the drainage system below the General Cañas Highway (or Route 1) would take three weeks. Now transit officials can only give a rough guess that the repairs will take “months.”
The pit, now four meters deep and nine meters wide, appeared in front of the Plaza Los Arcos in Ciudad Cariari, northwest of San José, several minutes from the Juan Santamaría International Airport. The turmoil that followed caused accidents, traffic jams and missed flights. By Tuesday, traffic flow returned to normal.
However, repairing the underlying damage will not be simple.
The Public Works and Transport Ministry (MOPT) and CONAVI could not decide how many months the repairs would take, although they assumed it would be done by the end of the year. Construction workers have begun the preliminary steps of installing a larger drainage system below the highway, MOPT said in a press release. After the work is finished, Bailey bridges will be placed on the opposite lanes of the highway so that the entire system can be remodeled and upgraded.
José Luis Salas, executive director of CONAVI, told the daily La Nación, “We could be talking about months.”
CONAVI engineer Cristian Vargas told crhoy.com, “We can’t say if it’ll take more or less than six months.”
A report Wednesday in the daily La Nación showed that the damage that occurred under the highway had been predicted four years earlier. In 2008, according to La Nación, a lawyer warned the Heredia Municipal Council that the road could be washed out. The information was based on a study commissioned by a local landowner.
The lawyer said the study warned that a tree trunk could fall into the La Guaria ravine, which flows under the highway, and block the drainage system, causing a collapse of the highway. That is exactly what happened last week.
The Heredia Municipal Council alerted CONAVI, but according to officials, they never received a response. CONAVI’s Salas responded that his department has conducted routine checkups along the highway.
Other studies by the Costa Rican Water and Sewer Institute and the University of Costa Rica’s National Laboratory of Materials and Structural Models concluded that urban growth in Heredia and lack of care caused the collapse of the storm drains.
Through the decades, the northern province of Heredia converted its expanse of coffee plantations into residences and businesses. Rainfall in central Heredia flows out of the newly urbanized area and into the La Guaria. During heavy downpours, the ravine becomes overwhelmed by storm water, and the weak drainage system is put at risk.
News station Telenoticias Channel 7 reported that the Bailey bridges on General Cañas cost 150 million ($300,000). The news report, citing CONAVI data, noted that Costa Rica has more than a kilometer of Bailey bridges installed in the country. Telenoticias concluded that the bridges, intended to be a temporary fix, remain in 80 different locations in the country.
The sinkhole area will be closed 10 p.m-5 a.m. every day until repairs are completed.