Dharma Initiative
The Swan was planned to be a laboratory used by the Dharma Initiative for research on electromagnetism. In the episode "The Incident", Dharma Initiative member Radzinsky claimed when complete, the Swan Station would allow manipulation of electromagnetism that "would change the world". According to the feature "Access Granted" on the third season Blu-ray, Dharma drilled into the earth and hit an area containing a large electromagnetic buildup, which their drilling released. The Swan was built over this area to act as a cork. Dharma then came up with a scheme to "dam" the leak but with the drawback that the field built up behind the dam and would eventually break it. A failsafe key could be used to permanently "seal" the leak. The specific event happened in July 1977, as revealed in "The Incident", and necessitated the evacuation of the island.