National Smart Transportation Archive Researcher

Document Type


Publication Date


Subject Area

operations - traffic, infrastructure - vehicle, planning - travel demand management, land use - planning, ridership - commuting, ridership - demand, policy - parking, organisation - management, mode - bus


Air quality, Best practices, Businesses, Case studies, Databases, Managerial personnel, National Smart Transportation Archive Researcher, Parking, Public transit, Single occupant vehicles, State of Washington, Strategic planning, Traffic mitigation, Travel demand management, Vehicle miles of travel, Washington (State), Work trips, Worksite


The objective of the National Smart Transportation Archive Researcher (NSTAR) is to develop an online, updatable, easily searchable database of case studies reliably documenting the effective use of transportation demand management (TDM) strategies to reduce vehicle miles traveled (VMT) and single occupant vehicle (SOV) mode share. The database is intended for use by transportation professionals and worksite employee transportation coordinators to develop and improve the effectiveness of their own programs for the purposes of reducing traffic congestion and improving air quality. The database is located on the Help Desk of the National TDM and Telework Clearinghouse at A Best Practices Guide was also prepared, which features 12 in-depth case studies of some of the most effective worksite trip reduction programs. These worksites are located in Washington State and the case studies were developed from data of the Washington State Department of Transportation Commute Trip Reduction Program and interviews with worksite employee transportation coordinators. These 12 worksites were selected from among 56 worksites that demonstrate a continuing performance trend of reduced VMT and SOV during the program years. The development of these worksite profiles employed a qualitative exploratory case study approach, which seeks to obtain a comprehensive understanding of the impacts of a given worksite trip reduction program taken as a whole and in its context. The case studies identified external factors, which are outside the control of the worksite, and internal factors, which are within the control of the worksite, that influenced program success. The study hypothesis was that internal worksite conditions can overcome adverse or unsupportive external conditions if the worksite trip reduction program is explicitly supported by the worksite management and the nature of the business also supports program success. All case studies were located within a mandatory regulatory environment requiring worksites to participate and produce results. This had the effect of guaranteeing some degree of management support to compare against generally adverse conditions of limited transit opportunities and plentiful parking conditions. Study results found evidence to suggest that worksite management support can overcome adverse external conditions; however, this support is more forthcoming when the outcome of a trip reduction program is aligned with business objectives.