Advancements in flooding techniques for leveling and thickening natural ice areas for improved Arctic Ocean operations resulted in the development of a mobile pump wanigan for confined flooding. An extra-wide NCEL camp wanigan was outfitted for confining and distributing the flood water, for drying and storing the flooding gear, and to provide a warm shelter for the construction personnel and sufficient illumination within 300 feet for ice construction at night. An experimental pump wanigan was evaluated at Point Barrow, Alaska, between 1958 and 1960, and selected components for the unit were evaluated at other field sites between 1960 and 1964. The mobile pump wanigan is well suited for thickening sea ice by confined flooding and is recommended as standard equipment for this type of ice construction. Specifications, reduced scale drawings, and commercial items were published in Technical Note N-608. Erection instructions are given in Technical Note N-587.