Robot lays conduit for cable in city's sewer pipes

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ALBUQUERQUE, N.M. - SAM keeps a low profile, slogging through the narrow pipes of sewers at night while a human above ground with a keyboard and two joysticks guides its every movement.

It's like playing a video game, manipulating the 3-foot cylindrical robot with bright red electric-powered wheels. But SAM, or Sewer Access Module, is no toy.

SAM is laying the fiber-optic cable so essential to downtown Albuquerque's broadband future - while allowing it to avoid urban chaos.

Most major U.S. cities, obliged by the 1996 Telecommunications Act to permit virtually any telecom to lay cable, have allowed contractors to rip up streets and sidewalks in order to fill trenches with fiber.

Albuquerque is the first American metropolis to give the job instead to SAM, which made its fiber-laying name in the sewers of the medieval German cites of Hamburg and Regensburg.

"God, it's just a winner all around," says Mayor Jim Baca.

No chewed-up streets. No traffic jams. And perhaps best of all, a benefit for taxpayers.

Albuquerque's new fiber-optic network costs the city nothing. In fact, Baca says it will earn about $1.5 million for leasing its sewers for the next 20 years to CityNet Telecommunications, the Silver Springs, Md., company that owns SAM.

Company officials say the robot-assisted work is about 60 percent faster than traditional fiber-optic installations and costs about half as much.

And there's a hidden, long-term benefit of avoiding trenched streets.

Cutting pavement inevitably means some moisture gets in, dropping a street's life expectancy by an average 25 percent and costing cities tens of millions of dollars, said CityNet senior vice president Cyrus Bamji.

Baca counts another advantage: CityNet's ability to inspect sewer pipe as it lays cable, pinpointing what might need repair in the future. CityNet also does cleaning and some repair, Bamji says.

CityNet is a "carrier's carrier." It leases fiber optics to retail telecommunications providers, who in turn sell data and voice services to customers.

The company links fiber-optics in buildings with major rings of fiber cable already installed by telecommunications and cable firms, providing the crucial last-mile connection for fiber, which carries thousands of times the data of traditional copper wire.

Here's how SAM works: A three-person crew climbs through a manhole with the 141-pound Swiss-made robot, whose digital video cameras act as the operator's eyes.

The crew positions the robot in sewer pipes that range from 8 to 20 inches in diameter, and it trundles along, installing stainless steel circular cable mounts every few feet along a pipe's inner circumference. The robot next threads three stainless-steel conduits to the mounts to house fiber-optics cable.

Once that's done, the crew hand-feeds optical fiber through the conduit. SAM can lay about 200 to 300 yards of cable a night, including mapping, rings and conduits.

SAM works at night because although it doesn't dig up the streets, the crew must block off the manhole with traffic cones.

The robot's work is also best done at night because it operates in what officials term "a living sewer environment" - and there's less flow overnight.

Bob Berger, CityNet's chief executive, is a telecommunications lawyer who serves on the Washington Suburban Sanitary Commission.

Pondering the fiber-laying problem a few years ago, he recalled that Chicago built a downtown fiber ring in abandoned tunnels that once took coal for heating into pre-1950s buildings. But that was a one-city solution. What about sewer pipes? he thought. Every building has one.

Berger formed CityNet in the fall of 1999. He found SAM at Ka-Te System AG, the Zurich company that developed it for the sewer revitalization business.

Though designed specifically for fiber-optics installation, SAMs descend from a generation of robots built for grinding and other sewer rehabilitation work.

Albuquerque is the world's third city to use robots to install commercial fiber. Omaha, Neb., and Indianapolis have signed agreements for installations later this year.