Go Down, Robot

After C. Michael Garver bought a robot-tunneling machine, he was so far ahead of the pack, he had to drum up his own competition

When C. Michael Garver rolled into Houston in 1965, he was the classic first chapter. With a degree in mechanical engineering in his pocket and his possessions loaded in a trailer, he was ready to take off after anything that looked legal and big. At the time, the city was growing frantically, with buildings going up all over town. Garver knew that all the action above the surface had to have its reciprocal below, in water and sewer projects. Not everyone appreciates the scale of the infrastructure industry -- out of sight, out of mind -- but Garver did. (U.S. municipalities spend more than $5 billion a year on capital improvements for sewerage and wastewater treatment alone.) And Garver wanted a piece of the action. In 1972, after a few years of selling draglines (Texan for "cranes"), he and two partners started a contracting company, BRH Inc., intending to specialize in underground construction. Nine years later Garver took control of the enterprise, recasting it in his own image as BRH-Garver Inc.

The specialty had been laid claim to for decades, and Garver, like any newcomer in an established sector, had to carve his own path. That meant keeping an eye open for jobs that were novel or complicated, since a newcomer was unlikely to outbid companies on work they had done a dozen times before. It was from that perspective that he contemplated a Houston public-works job, posted in the fall of 1986, endorsing the use of a piece of machinery called a laser-guided microtunneler, a device neither Garver nor any other contractor in Houston had ever worked with. The job was worth nearly $10 million -- potentially the biggest piece of business yet in the short history of Garver's company. He remembers phoning a micro-tunneler vendor and asking what the learning curve was for the equipment. "You know how it is when you talk to sales," he says now. " 'Just slip tab A into slot B.' " Sales sent over a video, which Garver watched. Reassured, he made a low bid for the job, got it, and ordered one of the first microtunnelers to be sold in the United States.

Microtunnelers, also known as robot moles, were developed by the Japanese in the early 1970s as a means to lay pipe without first digging long trenches. The idea was to dig shafts at, say, successive street intersections, lower sections of pipe down into the shafts, and then push (or jack) the sections, laid end to end, until the first section hit the next shaft, while leaving the ground surface undisturbed. As the sections were being jacked from behind, the tunneler would grind along in front using a steerable digging or cutting mechanism, like a toothed wheel, to remove the "muck" and pass it back through the machine, through the pipe, and out into the shaft, where it would be lifted to the surface. The technology turned out to have many advantages: it reduced surface disruption, could accelerate production, and allowed contractors to dive right under the tangle of pipes that clutter the near surface of any city, avoiding service interruptions. By the early 1980s microtunneling was being used in several industrialized countries.

But not in the United States. Americans like to think of themselves as receptive to new technologies, but that enthusiasm is not much in evidence when it comes to machines for constructing roads, sewers, water mains, treatment plants, and other public facilities. The reasons behind the foot-dragging aren't clear (observers have suggested reflexively risk-averse bureaucracies, the worship of the low bid, contractor cartels, regulators, and lawyers), but the phenomenon is real enough. Until well into the '80s, the city engineers of Houston actually forbade the use of a backhoe for work on sewer lines, insisting that trenches be dug with an ancient device that worked by scraping digging buckets hung between chains up against the working face of a site. Those ladder-type trenching machines were clumsy, broke down constantly, and required huge crews to run. But they had been used forever, and the city was confident that they would not create a public-relations disaster. Some- times a contractor would do a job with a backhoe and then stick a trencher down in the cut while the city engineer made his tour. But most used the prescribed tools in the prescribed way, as their fathers had before them.

As the late '70s gave way to the early '80s, Houston city engineers realized that most of the sewer work done over the last 20 years needed to be replaced. For starters, the system included far too many pumps. Pumps are the weak points in any sewer system: the machines have to work 24 hours a day under difficult operating conditions and are constantly breaking down, backing up, or overflowing. The right way to build a sewer between points A and B is to let gravity do as much of the work as possible. That means allowing the pipes running between the pumps to fall as deep as possible. Cutting trenches 25-plus-feet deep in soft, water-saturated soil like Houston's is not only expensive but tricky: such "gumbo clays" are prone to cave-ins. The city had tried to build a cheaper sewer system, with short, shallow connections linked by hundreds of pumping stations, but the overflows were becoming a public nuisance. It was time to start over.

Garver's job would cover one area of renewal. It called for laying a new line through River Oaks, a politically well-connected neighborhood. Excavation on the scale required would have meant shutting up a lot of rich people in their homes for weeks. Tony Crisci, who was the civil construction manager on the job, says that acres of expensive, exotic, and presumably cherished plantings would also have been at risk. The public-works department had looked at the job in the '70s, winced, and shoved it to the bottom of its to-do pile. By the mid-'80s pressure from the Environmental Protection Agency had moved it to the top. By coincidence, an engineer consulting for the city, Calvin Morgan, had family in the British contracting culture and knew that in Europe the job would be microtunneled without a thought. Morgan began advocating the technology; the combination of his enthusiasm and the political constraints of the project opened the door. When the bid went out, microtunneling was written into the specifications, in place of the trenching-machine requirement.