The Central Pacific and Union Pacific Railroads were designated by an Act of Congress in 1861 and 1862. Building was slow after construction began the route East from Sacramento in 1863. Financial problems and a labor shortage resulted in only 50 miles of track laid within the first two years. Although the Central Pacific needed over 5,000 workers, only 600 were on the payroll by 1864 - and the Union Pacific faced similar problems in encouraging workers to travel to Kansas to join the effort.