Multimodal Trip Generation Model to Assess Travel Impacts of Urban Developments in the District of Columbia

Abstract

The research effort described in this paper aims to develop a state-of-the-practice methodology for estimating urban trip generation from mixed-use developments. The District Department of Transportation’s initiative focused on ( a) developing and testing a data collection methodology, ( b) collecting local data to complement the ITE’s national data in trip rate estimation, and ( c) developing a model–tool that incorporates contextual factors identified as affecting overall trip rate as well as trip rate by mode. The final model accurately predicts total person trips and mode choice. The full set of models achieves better statistical performance in relation to average model error and goodness of fit than either ITE rates alone or other existing research. The model includes sensitivity to local environment and on-site components. The model advances site-level trip generation research in two major ways: first, it calculates total person trips independent of mode choice; second, it calculates mode choice with sensitivity to the amount of parking provided on site—a major finding in the connection between parking provision and travel behavior at a local-site level. The methodology allows agencies to improve their assessment of expected trips from proposed buildings and therefore the level of impact a planned building may have on the transportation system.

Contextual Adjustment of the Institute of Transportation Engineers Trip Generation Rates for Small and Medium Urban Areas in Louisiana

“…According to the afternoon peak hour regression outcomes, the estimated coefficients of independent variables are significant at the 95% level, with the exception of the constant and residential density. The model explains 33% of afternoon peak hour trip variations in the data, which is much below other afternoon peak models developed in large metropolitan areas such as R 2 of 0.89 in California smart growth areas reported by Westrom et al ( 3 ).…”

“… Note : CBD = central business district. Source : Westrom et al ( 3 ), Clifton et al ( 5 ), Cervero and Arrington ( 9 ), Holtzclaw ( 10 ), Clifton et al ( 11 ), Ewing et al ( 12 ), Ewing and Cervero ( 18 ), Doulabi ( 19 ). …”

“…The ITE method ignores the impact of urban context on travel behavior and travel patterns. The absence of supporting information for applying the ITE rates across a range of urban contexts up to the 9th edition of the Trip Generation Handbook was another issue, which was improved in the 10th edition (3)(4)(5)(6).…”

“…Many researchers have improved the ITE estimates by supplementing them with specific local data ( 3, 7, 8 ). The majority of such studies have been focused on smart growth areas, transit-oriented developments, mixed-used developments, and even single land uses in heavily urbanized areas, while the impact of urban context to adjust the ITE trip generation rates in less intensely urbanized areas is ignored by many jurisdictions.…”

Multimodal Trip Generation from Land Use Developments: International Synthesis and Future Directions

“…Based on this insight, the paper also suggests several directions to guide future practice and policy in the field. This paper is focused on trip generation at the site level rather than the process within four-step travel demand models, which is a separate topic and does not typically consider the built environment at the local scale (9). This remainder of this paper is structured as follows.…”