A collapsible water vessel has a center hull section, a first plurality of hull extensions longitudinally slidable through an opening at a first end of the center hull section between extended and collapsed positions, and a second plurality of hull extensions longitudinally slidable through an opening at a second end of the center hull section between extended and collapsed positions. When the first plurality of hull extensions are in the extended configuration, adjacent hull extensions thereof form a sealing contact therebetween and an inboard most hull extension thereof forms a sealing contact with the center hull section. And when the second plurality of hull extensions are in the extended configuration, adjacent hull extensions thereof form a sealing contact therebetween and an inboard most hull extension thereof forms a sealing contact with the center hull section.