While thousands of travelers passed through the Salt Lake International Airport on their way home Sunday night, crowds were somewhat smaller and lines shorter than expected.

"Manageable" is how airport operations manager Tom Hill described the situation on what is traditionally one of the busiest travel days of the year."It was basically a normal day with more people than usual," Hill said. "There were no major problems of any kind."

He attributed much of the smooth going to good weather, which made it possible for most flights to land and take off on schedule. And travelers were generally patient and cooperative.

"People were very friendly and full of the holiday spirit," Hill said.

Airport officials had feared that the absence of short-term parking might pose a serious problem during the Thanksgiving weekend, but those fears were not borne out, Hill said.

"There was the usual Sunday evening procession of cars at the curb," he said. "We had plenty of parking and no serious difficulties."

Most of the air passengers were just passing through Salt Lake City en route to other destinations and did not tax available parking or the shuttle system, Hill explained.

The airport's short-term parking lots have been closed since January because of construction of a new, four-level parking terrace. The $30 million structure will accommodate 1,890 private vehicles and 688 rental cars. It is scheduled to open before the Thanksgiving crunch in 1991.

In the interim, passengers are being shuttled from the terminals to parking lots farther south.

Besides the normal holiday traffic, the airport handled a half dozen unscheduled flights that were diverted to Salt Lake City because of a fire in a fuel storage tank at Denver's Stapleton International Airport (see story on A3).