Large and Extra Large Angular Boulders We offer the best prices and services in emergency rip rap flood control in building materials industry. We use the hardest rock materials available; basalt, granite, rhyolite and limestone. Compare our quotes to other sources and you are going to see why we can provide you the fastest most effective flood control measures possible. We specialize in providing emergency rip rap rock materials for flood control government, commercial and residential properties. Our rip rap rock materials are in sizes if; 18 to 24 inch boulders 24 to 36 inch boulders 1/4 ton boulders 1/2 ton boulders 1 ton boulders 2 ton boulders and are used for; Flood control, Stream bed lining, River bank support, Erosion Control, Levee bank support, Storm surge protection.