Abstract: A containment boom having the shape of an elongated floatable flexible wall member which is capable of being wound on a spool and deployed therefrom as described. The floatable flexible wall member has a vented flotation tubular membrane. A flexible sheet-like skirt member is secured along the tubular membrane along a longitudinal axis thereof. A ballast is secured to a lower elongated edge of the skirt member. The flotation tubular membrane is provided with a plurality of collapsible individual spiral coils disposed internally of the tubular membrane. The membrane support coils are secured to a plurality of bases which are interconnected to one another by a flexible connecting joint or the tubular membrane. A pull cable is secured along a top part of the tubular membrane.