Knight Ridder reports that even the U.S. Coast Guard boat throttles down and moves aside when the Susan M., Alameda County's new 85-ft. homeland security patrol boat, blasts past Jack London Square toward San Francisco Bay. The Coast Guard boat is said to be a key component of the East Bay's defense against a water-side terrorist attack. But the county's twin-engine cutter -- a sleek fiberglass vessel with a menacing pair of .50-caliber machine guns adorning its bow -- provides proof that there's a new player in town when it comes to guarding the Bay Area from offshore intruders. Alameda County, led by its sheriff, Charles Plummer, has launched its own Marine Patrol Unit to bolster offshore security in an era when experts have pointed to cargo ports and other maritime operations as weak points in America's anti-terror armor. Plummer's initiative was at first greeted warily by county budget-keepers, who said three consecutive years of gaping fiscal shortfalls hardly created the environment in which to launch a new program heavy on equipment and personnel hours. Unit started in 2003 But with some shrewd budget-keeping of his own, Plummer created the unit in 2003 by tapping nearly $400,000 in savings left over when his department purchased a 31-foot gunboat. On the heels of that breakthrough, Plummer's office in October pulled off a maritime coup -- acquiring the technology-laden cutter from the U.S. Coast Guard for free. It was an acquisition hailed by officials at the Port of Oakland, which has struggled to obtain federal support for security measures it deems necessary to guard an operation that is ranked No. 2 on the state's list of likely targets for terrorism. The Susan M. was part of a small fleet of vessels tested by the Coast Guard two years ago, to see if they were preferable to the 87-foot and 110-foot coastal patrol boats that are the mainstays of the agency's homeland security mission. The smaller ships offered one primary advantage: They're faster, cruising at speeds up to 40 knots, as opposed to the 25-knot speed of the larger boats. Eventually, though, the Coast Guard decided to stay with the larger boats, whose steel hulls are more durable and tend to perform better in the open sea. This was an important consideration, given that the Coast Guard's homeland security mandate includes patrolling waters as far as 200 nautical miles offshore. Plummer said the idea of launching the marine unit occurred to him in the days after Sept. 11, 2001, when he awoke one night nagged by worries about a potential terrorist attack at or near the Port of Oakland, where some of the world's largest cranes line the shoreline. Economic importance In launching the boat patrol, Plummer's office is acting under state law that gives county sheriffs authority to protect the safety of marine vessels located in waters off their coasts. The state's harbors and navigations code also allows local law enforcement officers such as sheriff's deputies to stop and board suspect vessels navigating there. Around the clock Adding the second boat to Alameda County's fleet helps make the marine unit a seven-day-a-week operation. Even when the smaller gunboat is in dry-dock for repairs, Lambert and the unit's five other members are a quick ride away from any part of the bay aboard the Susan M. When the Marine unit was launched, Plummer named its first vessel the August Vollmer, after a Berkeley police chief of the early 20th century who originated the motto .