Canal del Dique
The Canal del Dique ( Levee Channel) is a 118 km canal connecting Cartagena Bay (at the town of Pasacaballos) to the Magdalena River in the Bolívar Department in northern Colombia. Its eastern portion forms most of the border between the departments of Bolívar and Atlántico. The port on the Magdalena is Calamar. The canal was needed since the mouth of the Magdalena River (which provided access into the interior of Colombia) was virtually impenetrable, and Colombia's two main colonial ports (Cartagena and Santa Marta) had no access to the river. It was built by the Spanish  in 1582 but quickly fell into disrepair; it was rebuilt in 1650. However, by the end of the 18th century, it had become impassable except during times of high runoff, and by 1821 it was completely blocked. Thus, trade moved increasingly away from Cartagena to Santa Marta and Sabanilla (a port near the mouth of the Magdalena, later eclipsed by Puerto Colombia and Barranquilla). By 1831 traders in the city began to lobby for the canal's reopening, but repeated efforts to redredge the channel failed and by the end of the 19th century a railroad had replaced it. In  1923 and 1952, the canal was improved, but use then began to decline due to increased sedimentation of the Magdalena River. Currently, a modernization of the channel is being considered in order to boost trade in the port of Cartagena. The canal figures prominently in Gabriel Garcia Marquez's novel "Love in the Time of Cholera". George Totten an engineer, helped build this canal Since 2013, river diversions have been planned with Dutch company Royal Haskoning DHV to control sediment and water flow along the canal. This has led to creation of a new mangrove wetland area, land building and  ecological restoration in the region.