Abstract:Theoretical studies have suggested that parking and traffic conditions in cities are related, yet few empirical studies have been conducted to quantify this relationship. This paper develops a data processing procedure to extract and fuse data on time-varying parking garage occupancy and traffic speed at the street or city-block levels, and their relationships are studied. Parking occupancy data from the application program interface (API) in SFPark.org and comprehensive traffic speed data from the HERE Maps traffic API were used as a case study. During the morning and evening commute periods, the relationships between average speed and parking occupancy were found to be distinct, and both relationships could be modeled by a reversed logistic function. Such a macroscopic relationship can be exploited to evaluate the effectiveness of downtown access control or congestion charging.