A promising time saving technique has been developed in the construction of the new $14,000,000 Benicia-Martinez Bridge in northern California. The method involves floating, reinforced concrete boxes, 44 by 86 by 25 feet, which are cast on dry land, launched like ships, and towed to the bridge site by tugs and then anchored in place. In construction, the footing is first securely anchored into position and 6 foot steel caissons are then lowered through each of the 10 steel 80 inch pipe sleeves. The caissons are then sunk to bedrock, 130 feet below mean sea level. To sink the 6 foot diameter steel caissons into bedrock, the construction crews first lower a temporary 80 inch diameter casing into the water. The next step is to lower a 78 inch rotary drill and air lift pump into the temporary casing and to drill and pump out the material down to bedrock and two feet into it. A reinforcing steel cage is then placed in the bottom and concrete is placed up to the footing block.