As might be expected, engineers and others offered differing opinions concerning the various plans. One such engineer was Baron Godin de Lépinay (Nicholas-Joseph-Adolphe Godin de Lépinay, Baron de Brusly). The chief engineer for the French Department of Bridges and Highways, Lépinay was known for his intelligence, as well as his condescending attitude towards those with whom he did not agree. He was the only one among the French delegation with any construction experience in the tropics, 1862 construction in Mexico of a railroad between Cordoba and Veracruz. At the congress, he made a forceful presentation in favor of a lock canal.
The de Lépinay plan included building dams, one across the Chagres River near its mouth on the Atlantic and another on the Rio Grande near the Pacific. The approximately 80-foot height of the artificial lake thus created would be accessed by locks. The principal advantages of the plan would be the reduction in the amount of digging that would have to be done and the elimination of flood danger from the Chagres. Estimated construction time was six years. Since this plan required less digging, there would be, according to prevailing theories that tropical diseases were caused by some sort of toxic emanations coming from freshly dug earth being exposed to the air, less such problems. The de Lépinay design contained all of the basic elements ultimately designed into the current Panama Canal. The French company would use these concepts as a basis for the lock canal they would eventually adopt in 1887 following the failure of their sea level attempt. Had this plan been originally approved, France might well have prevailed in their canal construction effort. Had it been adopted at the beginning, in 1879, the Panama Canal might well have been completed by the French instead of by the United States. As it was, however, the de Lépinay design received no serious attention.