means such as shown in my prior application u s ser no 08 175 747 now u s pat no 5 374 133 to secure it to tube 12 skirt 14 is a sheet formed of a fluid impervious material which is secured along its upper portion 39 to the lower portion of tube 12 alternatively tube 12 and skirt 14 can be integrally formed the lower portion 40 of skirt 14 forms a compartment 42 which runs the length of tube 12 and has provided therein as best seen in fig1 weight or ballast means 18 for maintaining tension in skirt 14 when boom 10 is deployed and inflated as will be discussed further herein ballast 18 in the preferred embodiment takes the form of a heavy chain 18 a however in an alternate embodiment it can take the form of particulate matter having a specific gravity substantially greater than that of water see my prior application u s ser no 08 175 747 now u s pat no 5 374 133 tube 12 is filled by known means such as pressurized gas or foam to provide buoyancy see my prior applications u s ser no 08 175 747 now u s pat no 5 374 133 and ser no 08 851 124 filed may 5 1997 respectively as best seen in fig1 and 3 boom 10 is provided.