Union Pacific Railroad will continue improving Arizona's transportation infrastructure with a $6.9 million investment to enhance the rail line that runs from Yuma to Welton.

The 30-mile project includes removing and installing new rail and more than 47,000 railroad ties along the railroad corridor through southern Arizona. Crews will spread 18,000 tons of rock ballast to ensure a stable roadbed.

UP plans to spend approximately $3.2 billion in 2011 to support America's current and future freight transportation needs and enhance the safety and efficiency of the railroad's 32,000-mile network.