Salt Lake City finally has a transit-oriented development zone.

Property owners along the city's burgeoning 400 South corridor, which is home to a large section of the University of Utah light rail line, are now free to build residential units much higher along the corridor.

Buildings that include residential components can be built up to 75 feet high and may potentially go up to 125 feet high through a conditional use process.

The new zone passed Tuesday after years of wending its way through the city bureaucracy. Mayor Rocky Anderson has been pushing the ordinance and has often criticized the council for holding it up.

Council members, in turn, said the ordinance has had problems, and because such tall buildings are allowed they wanted to get it right before approving it.

City leaders hope the new zone will encourage more dense development along the 400 South transit corridor. The idea is to encourage dense development along transit lines, as smart-growth planning advocates suggest.

The new zone runs from 200 East to 700 East on 400 South and includes a small section of 400 South between 900 East and 925 East. The council decided not to rezone the areas on 400 South between 700 and 900 East because they wanted to protect the single-family dwelling units in the area. Some council members thought they banned the dense development in all areas east of 700 East but did in fact allow for dense development for a quarter-block east of 900 East.

Several residents spoke out against the 125-foot limit, which they said was too high.

"We're a little bit shocked," Kris Johnson said. Several residents said they were under the impression that 75 feet would be the maximum with not exceptions.

But Councilwoman Nancy Saxton, who represents the area, said that such dense housing development is needed to combat sprawl in Salt Lake County.

The people who argue against 125 feet "are the same people who would speak out against sprawl."

"Unless we're willing to increase the density at some time there's nowhere to go but out," she said.