Abstract: A pontoon flotation device having forward and rearward ends and including at least two parallel pontoons fastened to a substantially rectangular deck panel. The deck panel has upturned side flanges extending the length of each side of the deck panel with a pontoon located parallel to and beneath each side of the deck panel. Each pontoon includes a substantially rectangular bottom panel and inner and outer upwardly extending side panels joined to opposite long edges of the bottom panel. The outer side panel extends upwardly beyond the furthest upward extension of the inner side panel to extend parallel and adjacent to a side flange of the deck panel. By this means, the deck panel and outer side panel of the pontoon are in position to be conveniently fastened to each other.