The transport ministry says it will take five months and $3 million to fix the washout under the General Cañas highway.
This is the so-called crater that developed after a heavy rain in the westbound lanes. The Consejo Nacional de Vialidad installed twin bailey bridges to span the damaged area, and workmen have been underneath the bridges evaluating the situation.
Friday the Minister de Obras Públicas y Transportes said that it would build what they called a false tunnel under the roadway.
The job will be done with nine concrete arches, each 6.4
meters high (21 feet) and 7.5 meters wide (nearly 25 feet).The false tunnel will be 52 meters long, some 171 feet.
The Consejo will be closing the highway’s westbound lane from 8 p.m. to 5 a.m. every day to complete the work, it said. Eventually 18 arches will be installed because plans are to put the tunnel under the eastbound lanes, too. Each of the 18 prefabricated arches will weigh about 20 tons, said the Consejo.
Putting the arches under the eastbound lanes will require moving the bailey bridges from the current location in the westbound lanes. The tunnel is designed to carry water runoff under the highway. It was water and a tree trunk that collapsed the former culvert. Workers also will have to build a retaining wall.