Tim Welch


Assistant Professor of City and Regional Planning
Assistant Director, Center for Quality Growth and Regional Development
(404) 385-5114

View Welch's C.V.


Dr. Welch is an Assistant Professor of City and Regional Planning at the Georgia Institute of Technology. An expert in the field of transportation & land use policy, planning & forecasting and freight, he holds graduate degrees in law and urban planning. Welch is widely published, with a recent focus on issues related to transportation behavior, connectivity, equity and environment.

Educational Background

2013 - PhD (City and Regional Planning), University of Maryland, College Park

2010 - Master of Planning, Florida State University

2008 - Juris Doctor (JD), University of Detroit

2008 - Bachelor of Laws (LL.B), University of Windsor

2004 - Bachelor of Business Administration and Finance, Washington State University


Current Research Projects:

“A Data Driven Approach to State Transportation Investment Decisions: a Transportation Project Investment and Evaluation Resource (T-Pier),” PI

The primary objective of this research is to provide a data-driven resource that planners and engineers, policymakers, service providers and researchers can use to determine how investments should be made in the future by balancing available resources to maximize return on investment (ROI). This is achieved in three ways: (1) development of a multi-criteria investment performance tool to measure the economic contributions of performance measures by simulating travel behavior in response to each potential project, (2) development of a resource allocation toolkit to prioritize all potential projects to optimally distribute funds subject to budget and other constraints and (3) inclusion of sophisticated financial instrumentation to measure long-term ROI.

The proposed research will deliver a comprehensive decision support system in one toolbox called the Transportation Project Investment and Evaluation Resource (T-PIER). T-PIER will be equipped to examine the performance of each objective in small and medium scale transportation networks with multiple interacting modes such as driving, biking, and walking. The proposed tool will assist planners and engineers determine the optimal allocation of projects for obtaining maximum benefits when resources are limited and scarce. The proposed T-PIER framework combines both a travel demand and resource allocation model to interactively communicate and obtain an optimal set of projects to maximize ROI.

“Freight Impacts on Small Urban and Rural Areas,” Co-PI

This study focuses on the impacts of freight activity on rural and small urban areas, using hyper-local data to analyze current and forecast future truck movements along rural corridors. The current body of research and reports has relied on highly aggregate data, usually at the county level and often at an even larger geographic scale to make predictions about truck origins and destinations. Better estimates of truck activity are available and can be used to investigate individual congested freight corridors and roadways and their impact on economic activity, particularly in rural areas where freight movements are not as well understood. Improved disaggregate truck data can better inform local decisions for specific improvement strategies and projects. The study improves upon existing research by integrating the use of real-time (GPS) truck activity data, growth in major economic sectors, detailed route information and growth in port activity to analyze the flow of freight and its likely impact on smaller geographic areas

“National MAP-21 Implementation and Monitoring,” Co-PI

The “National MAP-21 Implementation and Monitoring” project examines the efforts that states and MPOs have undertaken to adopt a performance-based planning process, by contextualizing the relevance of adopted measures and comparing to other important indicators. Based on this work, and supplemented by information collected from DOTs and MPOs, a national database to benchmark performance progress will be developed. The database development process will identify desired transportation system performance characteristics and performance measures and evaluate them within the context of specific performance targets. This effort will be conducted in accordance with the recently articulated MAP-21 national requirements and those for MPOs and DOTs. It will also examine strategies to integrate these performance measures into statewide and regional planning processes. The project team will gather data from each entity to construct a database that will benchmark and track national progress on performance indicators.

“Statistical Analysis of Atlanta Parks and Recreation Department Needs Assessment Surveys,” PI

The Atlanta Parks and Recreation department has collected a large number of surveys from park users, measuring the demand for park amenities. The department is seeking assistance to statistically analyze the results of the surveys to provide meaningful results on park facility demand by local residents. The results of this analysis will uncover the underlying correlations between park users and their desire for specific park facilities.

Refereed Journal Articles:

Welch, T. F., & Mishra, S.  (2014). A Framework for Determining Road Pricing Revenue Use and Its Welfare Effects. Research in Transportation Economics. (Read It Now)

Welch, T., Mishra, S. (2014) Envisioning an Emission Diet: Application of Travel Demand Mechanisms to Facilitate Policy Decision Making, Transportation. (Read It Now)

Mishra, S., Welch, T. F., Torrens, P. M., Fu, C., Zhu, H., & Knaap, E. (2014). A tool for measuring and visualizing connectivity of transit stop, route and transfer center in a multimodal transportation network. Public Transport, 1-23. (Read It Now)

Welch, T. F. (2013). Equity in transport: The distribution of transit access and connectivity among affordable housing units. Transport Policy, 30, 283-293. (Read It Now)

Welch, T. F., & Mishra, S. (2013). A measure of equity for public transit connectivity. Journal of Transport Geography, 33, 29-41. (Read It Now)

Mishra, S., Welch, T. & Chakraborty (2013). An Experiment in Mega-Regional Road Pricing Using Advanced Commuter Behavior Analysis. Journal of Urban Planning and Development. (Read It Now)

Erdogan, S., Welch, T., Knaap, G. J., & Ducca, F. W. (2013). What to Expect in 2030: The Impacts of Fuel Price and Fuel Economy on Land Use and Transportation. Transportation Research Record: Journal of the Transportation Research Board, 2397(1), 89-98. (Read It Now)

Mishra, S., Welch, T., & Jha, M. K. (2012). Performance Indicators for Public Transit Connectivity in Multi-Modal Transportation Networks. Transportation Research Part A: Policy and Practice, 46(7), 1066–1085. (Read It Now)

Mishra, S., Welch, T. (2012). A Joint Travel Demand and Environmental Model to Incorporate Emission Pricing For Large Transportation Networks. Transportation Research Record: Journal of the Transportation Research Board 2302 (December 1): 29–41. (Read It Now)

Book Chapters

Welch, T., S. Mishra, & M.K. Jha (2012). Transit Service Indicators for Alternative Route Structure Analysis, in Applied Mathematics in Electrical & Computer Engineering (Jan. 2012), M.K. Jha, M. Lazard, and A. Zaharim (eds.), WSEAS Press, 45-50, proceedings of the 2012 WSEAS International Conference on Computer Engineering and Applications (CEA' 12), Harvard University, Boston, MA, Jan. 25-27, 2012.

Book Reviews

Welch, T. and Knaap, G. J. (2012), Perverse Cities: Hidden Subsidies, Wonky Policy, and Urban Sprawl by Pamela Blais. Journal of Regional Science, 52: 527–528. doi: 10.1111/j.1467-9787.2012.00780_13.x


Courses Taught

CP 6321 - Transportation Planning Methods and Investment Decisions (Syllabus)

This course takes an applied approach to the study of transportation planning concepts, relevant investment decisions and analytical methods. The course is composed of two components. The first part focuses on the economic and financial foundations of transportation. This includes the fundamental concepts the drive transportation demand, influence costs and supply, and effect investment decisions. The course will deconstruct the complex and sometimes adverse relationships between public/private investment and highway/transit provision. These concepts provide students with the theoretical underpinning necessary to understand how transportation investment decisions are made. 

The second part of this course takes a hands-on approach to transportation planning methods. Students are introduced to travel demand modeling. The course will delve into the common 4-step transportation demand model, the basic foundation for much of the transportation demand analysis that takes place in the U.S. Students will learn the mathematical underpinnings of each of the four steps and, with the aid of spreadsheets, use what they learn to conduct a simple alternatives analysis comparing two methods of organizing transit service.

This course combines principles of economics, management, engineering, operations research, and public policy to present a comprehensive view of how analysis methods and social political contexts can lead to various observed transportation investment decisions. 

CP 6331 / CEE 6624: Land Use and Transportation Interactions (Syllabus)

This course is about the contemporary American metropolis and the forces that shape it. The objectives of the course are to develop an understanding of the complex interaction between land use and transportation systems and, building on this foundation, to assess the implications of future transportation and land use decisions for urban growth and environmental quality. In the first component of the course, readings and group discussions will examine the historical and contemporary relationship between transportation investment and land use; including the basic theories of spatial organization and travel behavior.

The second and third components of the course will examine the social and environmental costs of decentralized land use and the principal economic, regulatory, and design-based strategies that have been employed to mitigate the undesirable effects of metropolitan growth. As air quality and climate change hold significant implications for future urban development, a particular emphasis will be placed on the linkages between land use, energy consumption, and air pollution. In the final component of the course, students will be introduced to the emerging integrated transport modeling framework and the major federal statutes governing the state and regional level transportation planning process. Through two lab projects, students will have the opportunity to perform their own analysis of land use and travel behavior with census demographic and travel survey data obtained from a major metropolitan area. The course will conclude with an overview of an integrated approach to land use and transportation planning.

CP6542: Transportation and GIS (Syllabus)

This course covers the applications of GIS and emerging spatial technologies to transportation. Its primary goal is to help students understand the basic principles of geographical information science for transportation, and to equip students with the state-of-the-practice computing technology for transportation planning in a GIS environment.

The course is appropriate for those with transportation experience and interested in learning practical implementation of transportation modeling in the GIS environment. It is also appropriate for those with a GIS background and interested in gaining experience in problems specific to transportation. The learning objectives of this course are to:

1) Understand transportation GIS fundamentals, including network, route and path, etc.
2) Increase proficiency in Transportation GIS routine operations such as data conversion, matrix operation, and topology building;
3) Become experienced in applying GIS to travel demand modeling and logistics analysis; 4) Explore creatively the applications of GIS to transportation analytical tasks, for example, accessibility modeling, urban mobility performance, health impact assessment or those specific to students' own areas of study and interest.