What floats these boats? Concrete

Does concrete float? For the hundreds of civil engineering students at the annual National Concrete Canoe Competition, the answer is "yes."

Teams representing 23 schools vied last week to design, build and race canoes made of concrete. Some vessels were as long as 22 feet and weighed as much as 180 lbs. A wooden canoe of the same size weighs about 40 lbs.

Alicia Welling, manager of the California Polytechnic State University team, says the trick to making concrete float is to mix it with glass bubbles and other lightweight objects.

Welling says the three-day American Society of Civil Engineers event gives students practical experience in finding creative engineering solutions and working as part of a team.

L'École de Technologie Supérieure, of Montreal, took the title Saturday.