With that study, he said, "We learned there were some areas that had wetlands vegetation but did not have wetlands soils, so those areas did not qualify as wetlands. So we have a little bit more room to refine alignments and minimize impact on homes" in West Point and Syracuse.
Jefferies said that cuts the maximum number of residential relocations from 69 to 50 homes.
It helped cut the maximum number of businesses that would need to be relocated from nine to four. And it helped reduce the maximum amount of prime farmland that would be lost to the project from 232 acres to 197.
"We've been working very hard to further minimize impacts," Jefferies said. "We've been talking to and hearing from residents, farmers, other agencies, city officials and a variety of stakeholders."
Tim Wagner, of the Utah Chapter of the Sierra Club, said Monday that he hopes UDOT exercises caution and confirms the findings before changing the corridor's alignment and possibly discovering later that the land really is wetlands.
The West Davis Corridor is projected to cost around $600 million for a 24-mile project northward from the end of the current Legacy Parkway to the West Haven area.
UDOT has proposed two main alternative routes for the project. It will announce a favored alternative as it releases its draft EIS next spring, which will be followed by public hearings and a comment period. UDOT hopes to have a final EIS and a final record of decision by spring of 2014.
No timetable has been set for actual construction of the project because no source of funding has been identified for it. But long-range regional-transportation plans envision most of the work to be completed within the next 10 years, with some stretches to be finished sometime in the next 20.
Detailed maps and descriptions of the project are available at udot.utah.gov/westdavis.
Pamela Manson contributed to this report.