Abstract: A contamination control boom arrangement for utilization in flowing bodies of water such as rivers, having both a contaminating liquid spill therein, as well as solid objects floating thereon. The boom has one end mounted adjacent the shore of the river and is swingable on the mounting so that the boom may assume various angles with respect to the direction of flow of the river. The boom has a rigid flotation means extending outwardly from the bank into the river and a plurality of fins pivotally coupled to the downstream side of the flotation means. Fin moving means are provided to vary the angle which the fin makes with the flotation means and thereby vary the angle which the flotation means makes with the direction of flow of the river. Fluid passageways are provided through the rigid flotation means at the water line thereof.