More than 50 commercial vessels were anchored outside ports in the Houston area at the end of last week, of which 41 were tankers, according to the Houston Pilots, an organization that assists in the navigation of larger vessels in and around port areas. Normally there are between 30 to 40 vessels anchored offshore, of which two-thirds are tankers, according to the pilots.
Although the channel has been shut intermittently due to fog or flooding in recent weeks, pilots said those issues were not significant enough to create the backlog.