Tempisque Bridge’s Lifespan in Doubt

TWO years after the highly applauded opening ofthe Tempisque Bridge, which spans the wide river of thesame name just north of the Nicoya Peninsula on thePacific coast, engineers are saying the $26.1 millionconstruction may not last as long as it should.According to a new study by the Federated Associationof Engineers and Architects (CFIA), the 780-meter bridge,which reduced travel time to the Nicoya Peninsula bymore than an hour when it replaced the Tempisque Ferryin 2003, needs help.Though no imminent danger exists, if action on certainproblems is not taken immediately, the bridge’smid- and long-term lifespan could be in jeopardy, CFIAexecutive director Olman Vargas said April 29.Known as the Taiwanese Friendship Bridge, the bridge was built with funds donated by thegovernment of Taiwan.CFIA has sent its report to both theTaiwanese Embassy and the Ministry ofPublic Works and Transport (MOPT).“The lifespan of a bridge is normally50 years,” said Carlos Fernández, the engineerwho performed the study. “It’s hard tosay how much life will be cut by the problemswe have seen; it depends on thebridge’s use.”HEAVIER vehicles such as semi-truckswill cause more damage, Vargassaid, adding, “but it would be very difficultto say only passenger vehicles can use thebridge.”Instead, the association is advocatingthe implementation of an intense maintenanceprogram to ensure the bridge’s long-termutility.The bridge opened April 10, 2003 forSemana Santa (Easter Holy Week),although access was limited while constructionwas finalized (TT, April 11,2003). The project was inaugurated severaltimes: first, while still incomplete, byformer President Miguel Ángel Rodríguez(1998-2003) on his way out of office andthen by President Abel Pacheco after constructiondelays set back its opening (TT,May 10, Dec. 6, 2002, March 28, 2003).THE structural integrity of the bridgeis not in question, Fernández assured.The problems at hand are the result ofa failure of two of the bridge’s cablemoorings during the bridge’s construction.In September 2002, during the tensioningprocess of the bridge’s cables,two of the moorings failed. This put additionalpressure on the other cables, particularlythose next to the failed moorings,Fernández explained. This in turncaused a deformation of the bridge’sbeams. Ultimately, the level of parts ofthe bridge’s surface slipped 70 cm.THE Tempisque Bridge is actually twobridges: a conventional bridge on theCañas mainland side, and a cable-stayedbridge on the Nicoya side. The point wherethese two bridges meet is also a cause forconcern, Fernández said. At this point,there is a 3-centimeter deviation from thenormal, making an uneven juncture.When the problem originally occurredin 2002, the bridge was temporarily jackedup and the damaged moorings werereplaced. This measure caused some of theproblems, and, according to Vargas, couldhave been avoided.“Other corrective measures would havegenerated a greater cost and taken longer,”he said, adding that the action was a decisionbetween the governments of Taiwanand Costa Rica.Regardless of who made or financedthe bridge, he added, CFIA considers it itsduty to regulate the quality and safety of allnational infrastructure projects.