Several years ago, wholesale prices for meth ranged from $15,000 to $20,000 a pound, he said. These days the price for that pound has dropped to between $3,000 and $5,000.

On the street, one-sixteenth of an ounce — called a teener — can sell for $100, Bianchi said. That small amount can equal four uses.

Meanwhile, the purity of the meth that is available has increased.

In 2008 the Iowa Division of Criminal Investigation lab reported an average purity of 35 percent for meth seized by law enforcement. By 2013, the average was 93 percent. Law enforcement agencies across the Midwest report that the influx of meth from large Mexican laboratories has pushed purity levels to 90 percent or more.

That means a given amount of meth, once mixed with filler ingredients, can supply more users. It also means the high that meth users get likely packs a larger punch, Daley said.

“It’s become almost a perfect science,” said Lt. Scott Wagner of the Douglas County Sheriff’s Office’s narcotics division. “(Cartels have) chemists doing it. Millions and millions of dollars put into these labs.”

Scott, of the State Patrol, said he doesn’t expect a change in the situation anytime soon.