A boom for the containment of oil spills and other debris on the surface of a body of water is formed of a curtain disposed at the surface of the water in a generally vertical plane with a lower edge of the curtain being submerged below the surface. Floatation for the curtain is provided by a set of floats secured within pockets of a flexible material which is sewn to the curtain. Stiffening members in the form of rods are secured transversely to the curtain at regular intervals between the floats. Weights are positioned at the lower ends of the rods to maintain the vertical attitude of the curtain. Ports at the bottom of each pocket admit water to the interior of the pockets while air escapes through the stitching. Water entrapped within the pockets greatly increases the virtual mass of the boom for resisting sudden lurches and rolling movements induced by waves of water striking the boom. After using the boom, the water is permitted to drain out of the pockets via the ports to provide a light weight, portable boom that is readily stowed.

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