ATC wraps up electric work in Zoo Interchange

American Transmission Co. has just completed its work in the Milwaukee Zoo Interchange to relocate and erect new electric transmission infrastructure to accommodate the Wisconsin Department of Transportation’s interchange expansion plans.

ATC began the transmission line portion of the project in June 2013 to relocate seven overhead 138-kilovolt transmission lines and erect 59 single pole structures to replace 58 lattice towers. 

“Residents and commuters were able to watch the transformation over the past year and a half while we removed the old structures, installed the new poles and strung wire across six lanes of traffic – all while the interchange was kept open to motorists,” said Barbara Mikolajczyk, ATC major project manager. “We were able to complete our work more than two months ahead of schedule because there was great communication and collaboration among the DOT and the multiple utilities involved.”

“Because ATC completed its portion of the project ahead of schedule, that helps our scheduling with other contractors this winter and next spring,” said DOT Construction Project Manager Mike Burns.

Project highlights include:

• Line energized and project complete: November 2014 – two-and-half months ahead of schedule
• Line length: approximately 11 miles 
• Voltage: 138,000 volts
• 58 lattice structures removed (circa 1954); equals 1.24 million pounds of steel removed
• 59 new single-pole structures erected; equals 2.3 million pounds of steel installed
• 40.5 miles of wire removed and new wires installed
• Transmission pole height: 115 to 180 feet; new poles are 50-60 feet taller than the lattice structures
• Tallest transmission pole: 180 feet with five sections, nine feet in diameter at the base and weight of 130,000 pounds
• Longest span between two transmission poles: 1,000 feet
• Project cost: approximately $50 million