A 2006 study by VDOT estimated that AM slugs along the I-95 corridor numbered about 6,450, which was about twice the number estimated in 1999 for this corridor. The 2006 estimates were based on morning peak counts at 15 slug line pickup locations along the Virginia I‐95 corridor. This includes sluglines in Fairfax and Prince William counties in the VDOT Northern Virginia District as well as locations in Stafford County and Fredericksburg in the VDOT Fredericksburg District. Source Virginia.gov.
Since the count was done in 2006 there were several parking spaces that were added along I-95 corridor. Most of the newly added parking lots in Prince William County are 100% occupied.
- 2011 – Potomac Mills Mall commuter parking lot, on February 14, 2011, the parking spaces available to commuters in the Potomac Mills Mall lot will be reduced from 1000 to 275.
- 2012 – Route 234 Commuter Lot – VDoT added 400 spaces to the existing 435 to a total of 845.
- 2012 – Telegraph Road Commuter Lot – Phase I, on September 6, 2012 Telegraph Road Commuter Lot with 553 spaces including 23 handicapped spots was opened for commuters
- 2014 – Telegraph Road Commuter Lot – Phase II, on August 12, 2014, Phase II projected added 176 new spaces to the 553 existing spaces included in Phase I to a total of 729 parking spaces, bicycle rack and lockers.
- 2014 – Route 610 Staffordboro Commuter Parking Lot with 1865 spaces was opened on September 15, 2015.