An upcoming bevy of major road and rail issues — and the studies that come with them — have overloaded Fairfax County transportation planners, according to the department’s director and county documents asking for outside help.

The numerous high-profile projects include the expansion of Metrorail to Dulles International Airport and a military base realignment at Fort Belvoir slated to send 22,000 new jobs there. The sheer quantity of work is outside the scope of the Transportation Department’s 21-member planning staff, according to Director Kathy Ichter, who on Monday said there is a “critical mass of projects coming all at the same time.” She expects to see studies in Annandale, Bailey’s Crossroads, Lake Anne, Tysons Corner and the Dulles Corridor, among other reviews.