Our Niagara Water Trays offer a natural environment in which children can experiment with water. The sliding dams can be used to retain water in the channels, illustrating cause and effect. HDPE plastic is used for the base of each square water tray and for the dams. All components are weatherproof and suitable for outdoor use. Constructed from pressure treated Scandanavian Redwood for long life. Each tray stands on pressure treated wooden posts which are installed into the ground.