KOBE -- Nearly 30 years after it was first proposed, construction of the controversial Kobe airport officially began Monday morning off Port Island amid protests and doubts about its economic feasibility.

The single-runway airport will be built at a cost of 310 billion yen on an artificial island. Scheduled to open in 2005, it will be the third airport covering the Kansai region.

At 8 a.m. Monday, vessels began setting up a large curtain around the reclamation site to prevent pollution from leaking into the surrounding bay, as about a half dozen protesters demonstrated on a yacht near the site.