Brennan Linsley, Associated Press
Cheyenne Fox attaches radio frequency tracking tags, required by law, to maturing pot plants inside a grow house, at 3D Cannabis Center, in Denver, Tuesday Dec. 31, 2013. Colorado is making final preparations for marijuana sales to begin Jan. 1, a day some are calling "Green Wednesday." 3D Cannabis Center will be open as a recreational retail outlet on New Year's Day,

SALT LAKE CITY — As Colorado prepares to become the first state in the nation to allow recreational pot sales, authorities in Utah are on alert.

"There's a profitable market for the substance over there," Summit County Sheriff Dave Edmunds said.

Beginning at 12:01 a.m. Wednesday, people ages 21 and over with a Colorado ID are able to buy 1 ounce of pot. Those from out of state can buy a quarter-ounce.

The U.S. Drug Enforcement Administration, Utah Highway Patrol and Summit County Sheriff's Office don't necessarily expect the illegal marijuana market in Utah to change, but they're quite certain they'll catch more high-level drug traffickers out on freeways in Utah as demand for marijuana grows in Colorado.

Summit County deputies, working with the DEA and UHP, have made it their business to intercept large marijuana shipments on I-80 and U.S. 40.

"We've seen an uptick of that in the last few years and in particular the last year or so,” Edmunds said.

Edmunds said he's certain that trend will continue. Denver law enforcement has ignored marijuana for years, he said, adding that he believes that drove up demand for the drug before voters legalized it.

"I think anytime you have a situation where law enforcement has decided enforcing certain laws are not a priority, I think you're going to see an uptick in usage,” Edmunds said.

The DEA also predicts more bulk marijuana busts and large cash seizures on I-80 and I-70. They base that estimate on supply and demand. The DEA believes marijuana growers in California, including Mexican cartels, will want to profit on the business in Colorado.

"Filling what would be a gap in Colorado relative to cultivators there not being able to keep up with demand,” said Sue Thomas, supervisory special agent for the DEA in Utah.

But the DEA doesn't foresee a big difference in illegal marijuana sales in Utah.

"Where we're going to see an increase is those transiting through Utah to market their marijuana products in Colorado," Thomas said.

The DEA does not plan to change its enforcement strategy.

"This has never happened before,” Thomas said. “Of course, our strategy is to always target the highest-level drug traffickers.”

The UHP said it will keep making marijuana busts the way it always has, through good traffic enforcement. It will stop motorists for traffic violations and equipment malfunctions, and sometimes those stops lead to pot busts.

For its part, Colorado set up an elaborate plant-tracking system to try to keep the drug away from the black market, and regulators set up packaging, labeling and testing requirements, along with potency limits for edible pot.

The U.S. Justice Department outlined an eight-point slate of priorities for pot regulation, requiring states to keep the drug away from minors, criminal cartels, federal property and other states in order to avoid a federal crackdown. Pot is still illegal under federal law.

Officials at Denver International Airport installed new signs warning visitors their weed can't legally go home with them.

With the additional police patrols, the airport warnings and various other measures, officials are hoping they have enough safeguards in place to avoid predictions of public health and safety harm from the opening of the pot shops.

Contributing: Associated Press