Possible Clues:

• Match alternatives
• Flat-bottomed barges
• Boats less substantial beginning to sink to the bottom
• They'll get pipes going in lake -- with people having a row that should be lead-free
• Smokers use them in boats
• Barges filled with inflammable liquid?
• Boats being slimmer, bow to stern
• Fire ships?
• Cigarette igniters or kind of boats