An apparatus for mitigating flood damage, the apparatus comprising: a supporting structure disposed within an interior of a flexible containment tube (10, 60) and comprising: a plurality of connected supports for giving shape and rigidity to the supporting structure, a cross sectional perimeter, and a length; the flexible containment tube (10, 60) comprising: a circumference greater than or equal to the cross sectional perimeter of the supporting structure, a length greater than the length of the supporting structure, an open end, through which the supporting structure can be inserted into the flexible containment tube (10, 60), and a valve disposed in a flexible body of the flexible containment tube (10, 60) configured to receive a fluid (61, 89, 92); wherein the length of the flexible containment tube (10, 60) exceeds the length of the supporting structure by a minimum fold length, wherein the minimum fold length is a minimum length of flexible containment tube (10, 60) necessary to extend past the end of the supporting structure and fold back onto the flexible containment tube (10, 60) to seal the open end of the flexible containment tube (10, 60). a supporting structure disposed within an interior of a flexible containment tube (10, 60) and comprising: a plurality of connected supports for giving shape and rigidity to the supporting structure, a cross sectional perimeter, and a length; a plurality of connected supports for giving shape and rigidity to the supporting structure, a cross sectional perimeter, and a length; the flexible containment tube (10, 60) comprising: a circumference greater than or equal to the cross sectional perimeter of the supporting structure, a length greater than the length of the supporting structure, an open end, through which the supporting structure can be inserted into the flexible containment tube (10, 60), and a valve disposed in a flexible body of the flexible containment tube (10, 60) configured to receive a fluid (61, 89, 92); wherein the length of the flexible containment tube (10, 60) exceeds the length of the supporting structure by a minimum fold length, wherein the minimum fold length is a minimum length of flexible containment tube (10, 60) necessary to extend past the end of the supporting structure and fold back onto the flexible containment tube (10, 60) to seal the open end of the flexible containment tube (10, 60). a circumference greater than or equal to the cross sectional perimeter of the supporting structure, a length greater than the length of the supporting structure, an open end, through which the supporting structure can be inserted into the flexible containment tube (10, 60), and a valve disposed in a flexible body of the flexible containment tube (10, 60) configured to receive a fluid (61, 89, 92); wherein the length of the flexible containment tube (10, 60) exceeds the length of the supporting structure by a minimum fold length, wherein the minimum fold length is a minimum length of flexible containment tube (10, 60) necessary to extend past the end of the supporting structure and fold back onto the flexible containment tube (10, 60) to seal the open end of the flexible containment tube (10, 60).