A controversial $90-million, 32-mile light-rail project in Austin, Texas, that entailed the tricky placement of a 932-ft-long cast-in-place bridge over a live railroad is slated for a December completion. The nine-station Red Line, developed by Capital Metropolitan Transportation Authority using revenue from a voter-approved 1% sales tax, uses a retrofitted segment of 100-year-old freight tracks extending from downtown northwest to Leander.

Lockwood, Andrews & Newnam, Inc. Austin’s first-ever light-rail system crosses live freight railroad tracks.

A key piece was a $5.5-million bridge near McNeil Road and Howard Lane over the Union Pacific Railroad. Austin Bridge & Road Inc. constructed the 25-ft-tall, 16.5-ft-wide structure set atop 18 piers. “Due to the inconsistencies in train times, it took us 12 hours to set 14 beams,” says Sofia Ojeda, construction coordinator for project manager Lockwood, Andrews & Newman, a unit of Leo Daly, Omaha. “For the spans outside the UPRR right-of-way, we were able to set 21 beams in 8.5 hours.”

Through last year and until this spring, cranes on both sides of the tracks picked prestressed beams from flatbed trailers. Oncoming trains sometimes halted work for an hour or more.

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Other contractors are completing a $5.7-million, 16,000-sq-ft rail maintenance building and $2 million of stations. Journeyman Construction LP, Austin, and Veolia Transportation Inc., Oak Brook, Ill., are retrofitting rail track to accommodate six 134-ft-long diesel-electric articulated cars manufactured by Switzerland-based Stadler Bussnang AG. Each $6-million, 800-hp train can travel up to 75 mph.

While the project reduces some congestion on Loop One and U.S. Highway 183, it does little else for other major roadways, critics charge. The dual-use route shifts 2,800 monthly freight trips to overnight hours, but proponents see it as a starting point for more transit in central Texas. “The rail line is the first step in a regional transit plan,” says Misty Whited, a Capital Metro spokeswoman.