By early next year, industrial partners Holly Corp. and Sinclair Transportation Co. could begin building a 400-mile petroleum pipeline capable of carrying tens of thousands of gallons of gasoline, diesel and jet fuel each day into Utah's Dixie and southern Nevada.

The price tag: $300 million.

The companies already have purchased the pipe and stacked it along the route as they negotiate the rights of way and permits needed to push the project south.

Those oil companies pitched their proposal Tuesday to the Salt Lake County Council, which oversees 15 miles of unincorporated land along the pipe's path.

Sure, the underground line could bolster profits for Wasatch Front refineries. But, project backers say, keeping an estimated 62,000 barrels of petroleum a day off Utah's highways also makes public-safety sense.

"Statistically, there is no safer mode of transporting that volume of product than a pipeline," said Jim Townsend, vice president of special projects for Holly Corp.

The idea of an interstate pipeline - which would flow from Salt Lake City to Tooele County before turning south - arose about two years ago to meet the rising fuel demands of southwestern Utah and southern Nevada.

Washington County boasts one of the nation's fastest-growing metro areas with a population that could swell to 648,000 by mid-century, according to company reports.

And Las Vegas is booming. Clark County motorists consumed 3 million gallons of gasoline daily in 2006, not to mention 1.27 million gallons of jet fuel at McCarran International Airport. That demand, according to documents presented Tuesday, likely will jump 25 percent during the next five years.

Once permits are issued, pipeline construction is expected to last nine to 10 months.

jstettler@sltrib.com