Photo Courtesy NEORSD

Talking Heads Project owners are using Twitter to update the public by speaking for the tunnel-boring machines. Above is Mackenzie, northeast Ohio's 1,500-ton TBM, showing its yellow-and-green cutter head.

Perhaps not since Bob the Builder have so many pieces of heavy construction equipment had so much to talk about. Instead of miniature, voice-overed claymation figures on a children's television show, Twitter is featuring actual tunnel-boring machines deployed at jobsites across the U.S. With some help from their human colleagues through social media, the TBMs are sharing observations about their work in real time while generating loads of followers.

In Cleveland, 1,500-ton Mackenzie (for Twitter account names, see box) regularly updates her progress in digging the three-mile Euclid Tunnel, part of the Northeast Ohio Regional Sewer District's (NEORSD) 25-year, $3-billion combined-sewer-overflow control program. Also assigned to a CSO project, D.C. Water's Lady Bird will soon start digging a four-mile tunnel beneath the Anacostia River.

On the West Coast, the San Francisco Municipal Transportation Agency (MTA) has introduced twin TBMs Mom Chung and Big Alma, which will team up to bore tunnels for the 1.7-mile Central Subway Rail Project.

The biggest Tweeter—both in physical size and number of followers—is Bertha, a 57.5-ft-dia TBM that soon will begin digging the new two-mile tunnel to replace Seattle's Alaskan Way Viaduct for the Washington State Dept. of Transportation (WashDOT). Since her Twitter debut in December, Bertha has garnered more than 3,500 followers.

Bringing Bertha to life via Twitter is a natural extension of the Seattle project owner's proactive use of social media. "A project of this size, with this much public interest, demands that we use a broad variety of communications tools to keep people informed and engage them in our work," says KaDeena Yerkan, WashDOT manager of communications. "Bertha's Twitter account helps us reach audiences that might not otherwise take an interest in the project."

The TBMs' Twitter activity typically focuses on project milestones as well as other non-controversial topics, such as sports and weather. "But one-liners with the other TBM accounts are always fun, too," says John Gonzalez, NEORSD social media coordinator.

On top of project updates, the agencies strive to give the TBMs personality. "It's not that hard to speak for her, usually, and it's fun," says John Lisle, D.C. Water's chief of external affairs and the voice of Lady Bird. "I think people still get a kick out of having a machine or some other inanimate object speaking to them. They know there's an anonymous person behind it, but they still find it entertaining if it's done right."

While Mom Chung and Big Alma have yet to begin work, their followers already seem quite interested in the machines and their Twitter personas, according to Erin Halasz of San Francisco MTA's Central Subways outreach team. "With Twitter, the complex, technical tunneling process becomes much more approachable for our community," Halasz says. "They engage San Franciscans in this major undertaking—the construction of our first new subway line in decades."

How do the TBMs feel about their newfound celebrity? See ENR.com for an exclusive group interview with Twitter's tunneling celebrities.