Trip and parking generation at transit-oriented developments: a case study of Redmond TOD, Seattle region

The decision on how best to allocate land around transit stations is a debated topic, with transit officials often opting for park-and-ride lots over active uses such as multifamily housing, office, and retail organized into transit-oriented developments (TODs). In this study, we identify the ten best self-contained TODs in ten regions across United States based on seven criteria: dense, mixed-use, pedestrian-friendly, adjacent to transit, built after transit, fully developed, and with self-contained parking. We measure trip and parking generation at one of these TODs, the Redmond TOD in the Seattle region, as a pilot study, using an onsite count and intercept survey. The results show that the Redmond TOD has 1.7 times more trips made by walking and 3 times more trips made by transit than Seattle’s regional average. The actual vehicle trips we observed are only 37 % of the Institute of Transportation Engineers’ (ITE) expected value. The actual residential peak period parking demand is only 65 % of the ITE’s peak demand, and the actual commercial peak period parking demand is only 27 % of the ITE’s peak demand. Additionally, the peak period of transit parking was daytime, while the peak periods of commercial and residential were evening and nighttime. There is a real opportunity for sharing parking spaces among these different uses, something which is not realized at present.