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14 TABLE 1 STATUS OF STATEWIDE MODELING CAPABILITY, SPRING 2005 Model Development State Condition Cost Time (years) Comments Alabama None Alaska None Arizona None Arkansas None California Operational $200,000 2.4 Colorado None $400,000 1 Connecticut Operational Delaware Operational District of Columbia MPO model Florida Operational $1,500,000 4 Georgia Operational $65,000 1 Hawaii None Individual island models Idaho Dormant Illinois Dormant Indiana Operational $1,500,000 3 7 more years for various upgrades Iowa Developing $300,000 2 Kansas Developing Has a dormant freight component Kentucky Operational $370,000 2 New model under development Louisiana Operational $500,000 Cost includes some applications Maine Operational $500,000 5 Being revised Maryland None Massachusetts Revising $800,000 Michigan Operational $1,000,000 2 Minnesota Partial Mississippi Developing Missouri Operational $500,000 Revision completion soon Montana Operational Freight only Nebraska Dormant Base year model Nevada None New Hampshire Revising $2,000,000 New Jersey Operational $500,000 Freight only New Mexico None New York None County-level OD assignment North Carolina None North Dakota None Ohio Operational $6,000,000 8 Being revised; $3,500,000 for data Oklahoma None Oregon Operational Being revised Pennsylvania Developing Rhode Island MPO model South Carolina Operational $25,000 0.5 South Dakota None Feasibility study being conducted Tennessee Developing Based on OD table estimation Texas Operational $1,700,000 4 Utah None Vermont Operational $730,000 2.5 Virginia Operational $1,500,000 3 Washington None West Virginia None Wisconsin Revising $850,000 2.5 Wyoming None Notes: MPO = metropolitan planning organization; OD origindestination. modeling capabilities. The District of Columbia and Rhode Is- RATIONALE FOR STATEWIDE MODELS land do not have statewide models, because they are covered Dynamics of Modeling Process entirely by a single MPO model. This table does not reflect the common practice of states using MPO models for rural travel Responses to the synthesis and Peer Exchange question- forecasting, when feasible. Those models shown as being re- naires revealed that the statewide modeling process is vised are already functional, but are either being updated or be- dynamic. A generalized process that has been followed by ing given greater capabilities. Figure 1 provides an additional several states is illustrated in Figure 2, which shows that the overview of the status as of spring 2005, as well as a rough es- design of the statewide model is influenced by past experi- timate of the cost of model development and, in a few cases, ences with the use of the model and by the levels of knowl- the amount of time allowed for model development. edge by both staff and decision makers. A statewide model

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15 development; the state of the practice in statewide modeling; the state of the art in travel forecasting, in general; and the availability and quality of secondary data sources. The de- sign of the model is also influenced by the level of expertise of the DOT staff and their consultants. Primary data sources can supplement secondary data sources, but at much greater cost. As staff expertise increases, the model can be upgraded for better accuracy and applications to a greater variety of policies and projects. Operational Dormant The most important feedback loop in the modeling process Developing involves five stages, shown counterclockwise in Figure 2: Revising Partial Goals and objectives, Model development funding, FIGURE 1 Status of statewide travel forecasting models, Statewide travel forecasting model, Spring 2005. Applications to plans and projects, and Outreach to decision makers. can flourish or become dormant depending on the amount of positive reinforcement that the process provides. Successful applications of the model lead to increased awareness and confidence among decision makers, who in The modeling process is driven by needs in the form of turn find additional uses for the model and provide the nec- general environmental and planning factors or by the require- essary financial support. Models that fail to continuously ments of a specific project, such as a major new highway cor- prove their utility will eventually be discarded. ridor study. The process is also influenced by the needed level of spatial detail. These needs lead to the development of goals and objectives for the statewide model. The goals may be ex- Uses of Models plicit or implicit, but are most often created in collaboration with decision makers and other stakeholders. The Guidebook mentioned the need to address certain Inter- modal Surface Transportation Efficiency Act of 1991 (ISTEA) The actual design of the statewide model is dictated by the planning factors as a major motivation for the development of established goals; the level of funding available for model statewide travel forecasting models. States with models reported an even broader rationale for model creation consid- Environmental Anticipated ering how the model is applied. and Planning Projects Factors Corridor planning (19) Statewide system planning or system environmental Desired Spatial Goals and Outreach to impact statement (EIS) (14) Detail Decision Objectives Makers Bypass studies (13) Regional planning, assisting an MPO model (12) Project-level traffic forecasts Model Applications to or project EIS (11) Development Funding Plans and Regional planning, substituting Projects for a local model (9) Air quality conformity analysis (6) State-of-the- Staff and Freight and intermodal planning (6) Statewide Consultant Art/Practice Travel Training Traffic impact studies (6) Forecasting Economic development studies (6) Model Long-term investment studies (6) Detour analysis (5) Secondary Project prioritization (5) Primary Data Data Sources Sources Toll, pricing, or tax studies (5) Border crossing or port-of-entry studies (4) Inputs to economic modeling (3) FIGURE 2 Typical statewide model development process. Intercity bus planning (3)

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16 Land use planning (3) Kentucky, Oregon, Florida, and Delaware, similar stories Passenger rail planning (3) exist in other states. Freight rail planning (2) Homeland security (2) Incident management planning (2) Ohio Operational level studies (2) Since coming on line in 2002, the Ohio Interim Statewide Travel Work zone planning (2) Demand Model has been used for many statewide and project- Airport planning (1) level analyses. The three most important are described here. The Weigh station location (1) model was used to analyze, verify, and update Ohio's Macro cor- ridor listing as part of the statewide long-range plan update. Revenue forecasting (1) Macro corridors are those that receive priority for capacity Pavement life studies, equivalent single-axle loads expansion. The model analysis was able to verify the existing (ESALs) (1) corridors, but also added several important corridors, many with Highway alternatives analysis (1) out-of-state connectivity that were missed in the original selec- tion process. The model was also used to estimate truck diver- Transit alternatives analysis (1) sion to the Ohio Turnpike, based on a truck speed limit increase Park-n-ride location analysis (1) and a decrease in truck tolls. This study was particularly sensi- tive because the bond rating of the Turnpike Commission was at The list of uses is in order of prevalence. The number fol- stake if the toll decrease resulted in decreased revenues. The model predicted an approximately 20% increase in truck traffic lowing an item indicates the number of states reporting that on the Turnpike (enough to offset the toll reduction) and this item. States having a long history with models and great con- amount was realized within a year of the changes. Finally, the fidence in model validity tended to report a greater number model was used to estimate the road user benefits (in terms of of uses. The list illustrates the wide variety of applications for travel time and vehicle operating cost but excluding crash costs) of the Governor's Jobs and Progress Plan. This plan envisions a statewide model. None of the states reported using their $5 billion in major new construction over 10 years. The analysis models for either truck weight studies or for safety analyses. focused on those projects involving capacity expansion (about half of the program in dollars) and demonstrated an annual user Although most states have found broad uses for their mod- benefit of $390 million per year over the 20-year life of the proj- ects, which was enough to validate the proposal (G. Giaimo, per- els once created, many models were initiated because of a very sonal communication, 2005). specific issue or project. For example Texas needed to analyze North America Free Trade Agreement (NAFTA) trade im- A description of Ohio's next generation model is found pacts, Louisiana and Wisconsin required input to their 2030 later in this synthesis. plans, Maine proposed to analyze a toll road, Rhode Island needed data for its air quality conformity analysis, and Indiana and Missouri were both writing an Interstate highway corridor Indiana plan. However, most models were started because of a real- ization by staff that there were general forecasting needs to be The Indiana DOT (INDOT) model was actually developed for addressed. California and Ohio identified these needs through the purpose of corridor-level economic development studies. a formal set of workshops. In Ohio's case, the process resulted The model has served as the basis for four corridor studies (I-69, SR-101, SR-37, and US-231). The model is used to produce in a model specification (for both an interim model and a final VMT and vehicle-hours traveled (VHT) output of existing plus model) and a program of data collection. committed network and build networks for level-of-service (LOS) deficiency analysis, corridor-level and systemwide eco- nomic analysis (in conjunction with a benefitcost add-on and Many states found it useful to stage the development of an economic simulation model). The model was also used to pro- the model, adding capabilities as the budget permitted. Cali- duce future year growth factors to forecast future traffic volumes fornia, New Jersey, Ohio, Oregon, and Virginia are examples in a statewide interchange assessment study. of states with a deliberate staging process--building a lim- The model output regarding link-level LOS for build and no- ited model to address immediate needs and expanding upon build conditions is a factor in project prioritization. INDOT uses this model to address a greater range of issues. the FHWA Highway Economics Requirements System with a 100% database to provide project-level benefitcost analysis and implementation phasing input to supplement the travel demand model. The statewide travel model provides future year traffic for Examples of Successful Applications of input into the FHWA Highway Economics Requirements System. Statewide Models The model is used at a systemwide level for safety analysis. In some locations the use of statewide models is multifac- The NETBC [Network Benefit Cost] costbenefit calculator computes accident reduction costs from model output VMT by eted. Information about historical uses was solicited from functional classification and facility type. states having recent, solid experience with applications. Sim- ilar information was also derived from the Peer Exchange The statewide travel demand model has been a valuable tool questionnaire, where states had an opportunity to expound on for INDOT in developing our 2030 INDOT Long-Range Plan. The model is used to display existing and future year congestion the rationale for model investment. Although this section problems for discussion at a series of INDOT consultation meet- provides example success stories from Ohio, Indiana, ings with our Metropolitan Planning Organizations and Regional

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17 Planning Organization. The model provides information on pro- model was used to evaluate the effectiveness of three alternative posed INDOT improvements and has been very valuable in the alignments to meet this objective. evaluation of improvements providing bypass alignments in NewbergDundee Bypass Induced Demand. An EIS is being smaller communities not covered by an MPO planning process prepared for a proposed highway bypass of two small com- (S. Smith, personal communication, 2005, and excerpts from the munities between Portland and McMinnville. The TLUMIP Indiana response to the Statewide Travel Demand Models Peer model was used to evaluate induced demand potential in rural Exchange 2004). Yamhill County as a result of the new bypass highway. Economic and Bridge Options Report. The TLUMIP model was used to examine the impacts of weight limits for vehicles using The Indiana passenger component is described later in deteriorating bridges throughout Oregon. This analysis was the this synthesis. basis for a discussion with the 2003 legislature and resulted in a $2.5 billion investment in Oregon's transportation infrastructure. Oregon Transportation Plan Update. The ODOT strategic policy Kentucky document for transportation is undergoing its first update since it was adopted in 1992. The statewide model is being used to help define a reference case and different transportation service and The Kentucky model has been used primarily for corridor investment scenarios (W. Upton, derived from the Oregon re- studies. sponse to the Statewide Travel Demand Models Peer Exchange Questionnaire, 2004, and personal communication, 2005). I-66 Corridor Study. The study limits were between the KentuckyVirginia state line and the KentuckyIllinois/ Missouri state line. The cost of the study was $1 million and Florida recommendations from the study were to implement (build) portions of a new I-66 corridor. The Kentucky Statewide The Florida model has a single focus. Model was instrumental in determining traffic volumes and the economic impact of the new corridor. A portion of I-66 is currently under design in Pulaski County. Other sections are The Florida Legislature established the Strategic Intermodal being staged for later letting dates. System (SIS) in 2003 to enhance Florida's economic competi- I-69 Corridor Study. This study stretched between Texas and tiveness. The system encompasses transportation facilities of Michigan. The Kentucky Statewide Model was used to deter- statewide and interregional significance and is focused on the mine the traffic volumes in the state of Kentucky. I-69 will be efficient movement of passengers and freight. These facilities built as a new facility in many locations (Indiana for instance), include Florida's major highways, rail facilities, airports, sea- and in Kentucky existing four-lane highways will be improved ports, and waterways, as well as the intermodal connectors join- and resigned. ing the SIS ports and terminals to its corridors. Other Corridors. The Kentucky Statewide Model has been used for many other important corridor studies such as I-64 The Florida Statewide Passenger and Freight Model has a (widening), I-875 (proposed new Interstate between Berea, highway network that includes all MPO model network links Kentucky, and Chattanooga, Tennessee), and I-74 (extension and major rural roadways. SIS highway links are identified in the of Indiana Interstate through Kentucky to Maysville). The model. Intermodal terminals, major seaports, and rail yards are model is able to give more accurate future growth rates and included as special generators. The model will be used to ana- traffic diversions than other available tools. lyze and evaluate conditions and performance of passenger and The Kentucky Statewide Model was used to optimize the lo- freight transportation under different scenarios, which will lead cation of potential commercial vehicle stations (weigh sta- to the prioritization of proposed projects for SIS planning analy- tions) by identifying the number of trucks that would use each sis (H. Shen, personal communication, 2005). location (N.R. Bostrom, personal communication, 2005). The Kentucky passenger component is described later in Delaware this synthesis. Delaware's model was recently updated and the Delaware DOT (DelDOT) has not yet had extensive experience with it. Oregon The updated model was immediately put to use as an integral Here is list of applications of the Oregon model for which tool within major studies of two long-standing, critical trans- portation issues. case studies have been prepared. The first effort was the US-113 NorthSouth Study initiated Willamette Valley Livability Forum. The Forum initiated a in fall 2004. This involved analysis of projected traffic conditions comprehensive regional visioning process for the future of and evaluation of more than 20 alternatives within a 50-mi-long land use and transportation in Oregon's populous Willamette corridor. The DelDOT Statewide Model was used to examine Valley. The first generation of the Transportation and Land "average annual conditions." Because the corridor is significantly Use Model Integration Project (TLUMIP) model was used to impacted by beach resort-oriented travel patterns at least 6 months model eight scenarios that varied by land use, road and public of the year, the model was expanded to include equations and transit networks, and mileage tax. Results of modeling various models focusing on "average summer conditions" and "peak combinations of land use, economic, and transportation policy weekend conditions." Development of the peak season models options allowed decision makers to see the effects of each pol- included postcard mailback surveys and other analyses to refine icy and how it will shape the future of the Willamette Valley. peak trip rates, OD patterns, develop a "day tripper" table, and re- House Bill 3090: Eastern/Central Oregon Freeway. The 1999 view summer assignment patterns on "beach routes." Oregon Legislature directed the Oregon DOT (ODOT) to ana- lyze whether a freeway in eastern and central Oregon would off- The second effort was the US-301 Environmental Impact load increasing traffic in the Willamette Valley. The TLUMIP Study initiated in spring 2005. This is a location and preliminary