DEEP reimplemented the system for the summer following what they say was a successful pilot program.
Parking passes for holidays and weekends can be purchased up to 14 days in advance or until 3 p.m. on the day of arrival, if capacity has not been reached.
Visitors can purchase up to two car passes at a time and must provide vehicle information for each pass, including a vehicle's license plate number.
Officials say advance reservations are not available or needed for weekdays and non-holidays visits.
They say booking ahead will reduce traffic congestion and improve visitors' experience.
Reservations can be made online or by calling 1-877-668-CAMP.