Tucson Electric Power's service outage affected at least 35,000 customers across much of Tucson Wednesday.
The boundaries affected were Tangerine to the north, 22nd Street to the south, Camino de La Tierra to the west and Alvernon to the east. The outage started just before 10:30 a.m. in downtown Tucson and lasted until just after 1 p.m.
Authorities say 40 - 50 intersection traffic lights were out because of the outage. The University of Arizona, the University Medical Center area and St. Mary's Hospital were all affected.
Some areas within those boundaries had power before 1 p.m., officials with University Medical Center reported to be unaffected by the outage, but other buildings nearby, like the College of Medicine, were operating on emergency backup power.
TEP officials say they've restored power to the University of Arizona campus just after 12 noon, Wednesday. TEP had advised that power outages affecting Tucson's west side and most of the University of Arizona may continue causing sporadic outages for much of Wednesday afternoon.
Officials with Tucson Electric Power say the problem is linked to a transformer at a substation, near downtown. Equipment failure at the substation limited use of a large transformer. Crews were trying to shift power onto adjacent circuits.
Crews resolved the problem by 1:00 p.m. Wednesday.
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