<P> Although chief engineer John Findley Wallace was pressured to resume construction, red tape from Washington stifled his efforts to obtain heavy equipment and caused friction between Wallace and the ICC . He and chief sanitary officer William C. Gorgas were frustrated by delay, and Wallace resigned in 1905 . He was replaced by John Frank Stevens, who arrived on July 26, 1905 . Stevens quickly realized that serious investment in infrastructure was necessary and determined to upgrade the railway, improve sanitation in Panama City and Colón, renovate the old French buildings and build hundreds of new ones for housing . He then began the difficult task of recruiting the large labor force required for construction . Stevens' approach was to press ahead first and obtain approval later . He improved drilling and dirt - removal equipment at the Culebra Cut for greater efficiency, revising the inadequate provisions in place for soil disposal . </P> <P> No decision had been made about whether the canal should be a lock or a sea - level one; the ongoing excavation would be useful in either case . In late 1905, President Roosevelt sent a team of engineers to Panama to investigate the relative merits of both types in cost and time . Although the engineers voted eight to five in favor of a sea - level canal, Stevens and the ICC opposed the plan; Stevens' report to Roosevelt was instrumental in convincing the president of the merits of a lock canal and Congress concurred . In November 1906 Roosevelt visited Panama to inspect the canal's progress, the first trip outside the United States by a sitting president . </P> <P> Whether contract employees or government workers would build the canal was controversial . Bids for the canal's construction were opened in January 1907, and Knoxville, Tennessee - based contractor William J. Oliver was the low bidder . Stevens disliked Oliver, and vehemently opposed his choice . Although Roosevelt initially favored the use of a contractor, he eventually decided that army engineers should carry out the work and appointed Major George Washington Goethals as chief engineer (under Stevens' direction) in February 1907 . Stevens, frustrated by government inaction and the army involvement, resigned and was replaced by Goethals . </P> <P> The US relied on a stratified workforce to build the canal . High - level engineering jobs, clerical positions, skilled labor and jobs in supporting industries were generally reserved for white Americans, with manual labor primarily by cheap immigrant labor . These jobs were initially filled by Europeans, primarily from Spain, Italy and Greece, many of whom were radical and militant due to political turmoil in Europe . The US then decided to recruit primarily from the British and French West Indies, and these workers provided most of the manual labor on the canal . </P>

History of the construction of the panama canal