Though the land will not formally become part of Herriman until Jan. 1, the City Council voted this week to adopt the area and, as a result, boost the suburb's size by more than 50 percent.

This formerly 8,000-acre city (population 15,000) will swell to more than 12,000 acres.

The expansion comes after the Utah Supreme Court ruled earlier this year that developers and landowners could bolt from neighboring Bluffdale, ending a 14-year tug of war between builders and Bluffdale officials.

"It feels like we just crossed the finish line in a marathon," a clearly relieved Don Wallace said after the annexation approval.

Wallace is the president of Sorenson Real Estate, which owns 1,400 of the newly annexed acres and is developing the massive Rosecrest community, now fully in Herriman's city limits.

Wallace added that if he had known in advance how much of a struggle he faced, he might not have taken on the project.

Developers had said Bluffdale (population 7,000) would not service the land when it was a part of that city. They also objected to Bluffdale's strict zoning rules, which call for one unit per acre.

In parts of Herriman, they will be able to build more than four times as many homes.

"We're looking at similar densities to what Rosecrest is now," said James Lee Sorenson, vice chairman of Sorenson Development. "We're really trying to develop something that's going to be attractive and meet the needs of the market."

And while he acknowledged that some Bluffdale folks suspect developers now will, out of spite, load the Bluffdale-Herriman boundary with high densities, Sorenson said he has no hard feelings and wishes the city well as it grows.

Dave Millheim a managing partner with Development Associates, which also owns a large chunk of the newly annexed land and is building a project called South Hills, said this week's annexation represents a big step toward reaching a development agreement with his new host city.

Herriman Mayor Lynn Crane said eight years ago, when his city incorporated, forecasters predicted the suburb's population would top out at 25,000 residents. But this week's “historic event” propels that figure closer to 75,000.

And Councilwoman Raquel DeLuca said the annexation would offer opportunities for commercial development to help sustain the mushrooming city.

“It's amazing,” she said, “just to see what's become of Herriman in such a short period.”

sgehrke@sltrib.com