Frequently Asked Questions

The EconWorks Case Studies are intended to support better planning by providing insight on issues such as 1) what makes some transportation projects have higher economic impacts, 2) the role of policy factors in enhancing economic benefits of transportation projects and 3) the influence of existing economic trends.

Currently the EconWorks Case Studies library includes 105 transportation projects searchable by project attributes. This database can be used to obtain estimates of the economic impact of potential projects based on parameters defined by users. Selecting many specific project attributes, such as specific project type and geographic location, may result in only a few or zero representative projects. Additional case studies are envisioned to be added to expand the breadth and depth of the case study database. The tool will also be recalibrated thus making it more representative. Any organization interested in developing a project case study is encouraged to participate in the on-line "Guide to Developing EconWorks Case Studies" training to learn the proper techniques and methodologies required to submit a case study for review and inclusion in EconWorks. This training is accessible by clicking “Case Studies” in the top menu bar and selecting “Training Modules.” Select “Submit A Case Study” to send in a proposed case study.

The AMP feature draws from the case study database to estimate the range of economic impacts likely to result from a specific type of project in a defined setting. It provides a form of “analysis by analogy” and is not meant to be predictive. Rather, it identifies a reasonable range for the expected impacts of proposed projects based on similar case studies. It is important to note that neither the searchable database nor the AMP features within EconWorks Case Studies provide information on the effects of changing traffic volumes, speeds, distances or safety, or effects of wider measures of changing reliability, connectivity or accessibility. These factors can play a substantial role in determining whether the actual economic impact of a project will be at the low end, high end or outside of the normally expected range. EconWorks Case Studies tool is not a substitute for detailed economic impact studies for individual projects.

Current research does not allow quantifying the specific level of influence that land use policies, supporting infrastructure and business climate had on projects. That is why the sliding scales are not labeled. The default setting for each policy slider is “average.” As such, the slider scales can be used to reflect the minimum, average, and maximum levels of policy influence. Specifically for each policy type, these ranges can be described as:

• Land Use Policies (Restrictive, Adequate, Strongly Supportive of Economic Development);

• Supporting Infrastructure (Not Available, Adequate, All-Inclusive);

• Business Climate (Negative, Adequate, Positive/Aggressive).

Currently, there are more large transportation projects than small projects in the database because case studies were easier to compete for the larger projects, as their economic development impacts tend to be more are significant and easier to identify. It is hoped that additional small project case studies will be developed in the future. Even with 10 project types in 6 regions (5 national, 1 international) totaling 105 case studies, there will still be gaps in coverage. Part of the strategy for additional case study development is to identify the coverage gaps that are most problematic and work with states, metropolitan planning organizations (MPOs), and other groups to address these needs in the future.

The initial case studies focused on highways. The EconWorks database is designed so that it can include intermodal and transit projects as it is expanded. Interested citizens and groups may request or propose including a case study, or volunteer to develop one by contacting AASHTO at econworks@aashto.org.

The EconWorks Case Studies database is designed to house a large number of projects over a long period of time, even though there are a limited amount of cases available today. This means that searching for a specific type of project may currently provide only a small number of cases. In these situations, users can decide which criteria are most important (e.g. geography or project type) and adjust the search categories to see if there are other case studies that address these criteria of interest.

The table of project’s pre/post conditions can be copied and pasted into Excel using Firefox, Microsoft Internet Explorer, and Google Chrome. In addition, a button “Export Results” (below the “Print Results” button) on the “Case Study Search” page enables the user to download all of the project and impact data for all cases after filling out their required contact information and a brief survey.

The case studies facilitate early stage exploration and analysis of issues and opportunities. The W.E.B. analysis tools are meant to complement and enhance benefit-cost analysis, economic impact analysis, and multi-criteria analysis. Specifically, the analysis tools can quantify accessibility, connectivity, and reliability improvements which are often left out of traditional benefit-cost analysis and economic impact analysis. Their overall purpose is to create the means for measuring economic development components that are not traditionally measured.

Regional economic simulation models such as REMI and TREDIS are indeed sophisticated, but to varying degrees they do not have the full capabilities and flexibility of the W.E.B. Analysis Tools to measure accessibility, reliability and intermodal connectivity. Some economic models lack connectivity and reliability inputs; others incorporate those factors but in a more limited manner. State DOTs and MPOs may opt to use the W.E.B. Analysis Tools together with regional economic models. In fact, NCHRP Report 786 discusses how these spreadsheet tools can be used to enhance economic impact models. Basically, they can be used individually as pre-processors that generate additional inputs for those models.

It is NOT necessary to hire an economist to deploy, use or interpret the results of the W.E.B. Analysis Tools. In fact, these tools were specifically designed to enable DOTs and MPOs to do preliminary screening and assessment work by themselves. NCHRP Report 786 walks readers through three case study examples which illustrate in great detail how a DOT or MPO analyst can obtain necessary data to enter into these tools, and then use them to calculate and interpret results.

Yes – please send your questions and comments to econworks@aashto.org