A consultant report is calling for a new $468 million 18-gate terminal on the south side of Des Moines International Airport, The Des Moines Register reported. Consulting firm Leigh Fisher reported the results of a seven-month airport facilities study today to the Des Moines Airport Authority board. The study recommended that construction begin in 2022, as the current facilities would be inadequate when annual passenger numbers reach 2.5 million, which is expected to happen by 2027.