Do Land Use, Transit, and Walk Access Affect Residential Parking Demand?

This paper describes a field study that was conducted in King County, Washington to investigate variations in parking supply and demand at multifamily residential sites. More than 100 factors were developed for data collection and analysis that could be grouped in five areas: parking supply and price; property/development characteristics; neighborhood household characteristics; accessibility; and built form/development patterns. The factors included independent variables such as average monthly parking cost to tenant, supply, density, distance to nearest transit stop, walk score, block size, and block density. Parking utilization was observed from Tuesdays through Thursdays between midnight and 5 a.m. at 208 sites. The parking utilization data was correlated with the 100 factors. Independent variable relationships were assessed for their predictive powers using linear regression methods. The results showed a clearly evident and statistically relevant variation in land use to multifamily residential parking utilization. A similar relationship existed between multifamily residential parking utilization and transit access. The relationship between the price of parking and parking utilization showed utilization declining as the percentage of parking cost to rent increased. The overall findings indicate that walk and transit access to trip destinations, block size, population and job density influence parking utilization, in some cases by as much as 50 percent. Most important, the research demonstrates that higher supply of parking appears to consistently correlate with greater parking demand. By verifying intuitive perceptions with data and fact, this research provides a new tool for use in considering the proper provision of parking.