Climbing costs are afflicting the construction of the key Coatzacoalcos tunnel connection in Mexico. Concesionaria Tunel de Coatzacoalcos is the firm handling the construction and concession for the Coatzacoalcos immersed tunnel. The company claims that costs have climbed 150%, from US$153.23-$383.1 million. Concesionaria Tunel de Coatzacoalcos is controlled by Spanish construction firm FCC Construcciones and says that the climbing costs are caused by delays due to the climate, problems purchasing land and increasing interest rates. When complete the Coatzacoalcos connection will be 2.28km long, carrying four traffic lanes under the Coatzacoalcos River. The tunnel will provide a new link between Villa de Allende and Coatzacoalcos. Construction commenced in February 2007 and the contract should be completed in mid-2015.