Thomas H. Spreen is currently professor and chair of the Food and Resource Economics Department at the University of Florida in Gainesville, FL. He has been on the faculty at the University of Florida since 1977.

Dr. Spreen was born and raised in a small town in central Indiana. His family was in the banking business. He graduated from high school in 1969 and went off to college with no idea what direction his life might take. After 1 year at Rose Polytechnic Institute, he transferred to Purdue University, where he earned a B.S. degree majoring in Mathematics and Statistics and a minor in Economics with highest distinction and was inducted into Phi Beta Kappa in 1973. He enrolled in the graduate program in Statistics at Purdue and earned a M.S. degree in 1974 while being supported by a university fellowship. He moved to the Agricultural Economics Department at Purdue in the fall of 1974. He received his Ph.D. degree in 1977 under the supervision of Bruce McCarl.

Upon his arrival at Florida, he taught courses in mathematics for economists and mathematical programming and began a research program in livestock marketing. His research at that time dealt with price analysis of livestock markets and the feasibility of expanded feeding and slaughtering of cattle in Florida. He developed an interest in bioeconomic modeling, which led to an edited book published in 1986.

In the late 1980s, he supervised a Ph.D. student who developed a mathematical model of the world orange juice market. This model was modified in 1992 to assess the impact of the proposed North American Free Trade Agreement on U.S. citrus producers. This work led to a shift in his research interests to citrus and other high-valued crops. He made his first visit to Mexico, which also opened up an avenue of research in collaboration with the University of Veracruz, in 1993.

He has authored or coauthored several publications on the economics of the world market for citrus products. These papers include collaborations with citrus experts from Brazil, Cuba, and Mexico. He has also worked as a consultant to the Food and Agriculture Organization of the United Nations regarding forecasts of citrus production and consumption on a worldwide basis.

He has been active in the graduate program of the Food and Resource Economics Department, having served as the primary supervisor of 50 graduate students, and has served on a total of 106 graduate supervisory committees. Several of his advisees hold prominent positions at academic institutions in the United States and overseas, in the U.S. Department of Agriculture, in other government agencies, and in the private sector. He twice served as graduate coordinator of the Food and Resource Economics Department, overseeing major changes in the doctoral program of the department and the establishment of a Master of Agribusiness degree program.

In the last 10 years, Dr. Spreen has been widely sought as an expert on the economics of citrus production and marketing. He has given presentations at numerous industry meetings in Florida as well as lectures on citrus related topics in California, Mexico, Cuba, Brazil, Belize, Italy, Spain, Portugal, and China.

He was appointed Chair of the Food and Resource Economics Department in 2002. Under his direction, the department has maintained its excellence in undergraduate programs, with enrollment nearly doubling over the past 3 years. The department has also partnered with the College of Business Administration to offer a M.S. degree specializing in entrepreneurship.

This first feature in a series on Milwaukee, WI, USA-site of the ITE 2006 Annual Meeting and Exhibit-focuses on how the Wisconsin Department of Transportation is managing community needs and traffic impacts during the reconstruction of the Marquette Interchange.

INTRODUCTION

In the heart of downtown Milwaukee, WI, USA, host of the ITE 2006 Annual Meeting and Exhibit, the busy thoroughfares of Interstates 43, 94 and 794 inter sect to form the Marquette Interchange. Built between 1964 and 1968, the fivelevel interchange is undergoing a complete reconstruction. A significant makeover was needed because the interchange structures were at the end of their useful lives; crash rates were high and traffic volumes were double the number the interchange was intended to handle when it opened.

Before the $810-million, 5.5-mile reconstruction could be launched, however, the Wisconsin Department of Transportation (WisDOT) needed to address and manage community needs in downtown Milwaukee.

The Marquette Interchange serves as the gateway to Milwaukee for residents, business and tourism. It links Milwaukee's economy to the rest of the state. A total of 66,000 people live in downtown Milwaukee, and 121,000 workers are employed at 4,300 businesses. More than 7 million tourists per year visit cultural attractions and festivals.

To manage the community's needs, the Marquette Interchange needed to be built in a way that kept downtown open for business and minimized the impact of construction on tourism. In 2002, three years before major construction would start, WisDOT gathered leaders from the community to develop ideas that would mitigate traffic impacts during the mega-reconstruction project.

NEED FOR A NEW INTERCHANGE

The main system interchange (1-43/ 94/794) originally was built with a combination of left-hand and right-hand ramps that were closely spaced to service entrance and exit ramps. This caused severe weaving movements that contributed to traffic congestion and crashes.

When the interchange was opened to traffic in 1968, drivers used studded tires during winters for better traction. However, the studded tires combined with salting operations caused the structures to deteriorate rapidly. The structures continued to deteriorate as time passed, and the interchange required complete reconstruction to avoid weight-limitation postings for trucks. Trucking restrictions would have been an obvious detriment to the state's economy.

The design of the reconstructed interchange eliminates the weaving sections by shifting all system and service ramps to the right-hand side; increases the design speeds of the system ramps to reduce the speed differential between the ramp and mainline movements; expands some system ramps to two lanes to provide additional throughput capacity; and lengthens the merging distances from ramps to mainline.

The future interchange will be built on the existing interchange's tight urban footprint, with only a small change in the total right of way required for the new interchange. The new interchange design is shown in Figure 1.

ANTICIPATED IMPACTS

Construction of the interchange is now in its second of four years of freeway impact. Preparatory work off the freeway began in 2004. The scheduled completion date for the entire project is December 2008, with the northern section of the project set for an interim completion date of October 2006.

To meet the needs of the community, the project team had to carefully balance keeping freeway lanes and ramps open while limiting the total time that the downtown interchange would be under construction. To facilitate construction, the east-west and north-south sections of the project are being built in halves. In 2005, the southbound direction of 1-43 was rebuilt while both directions of traffic used the northbound side, as shown in Figure 2.

To accommodate both directions of traffic on one side of the freeway, the sixlane section with full shoulders was reduced to a four-lane section with limited shoulders and lane widths. Almost 300,000 vehicles use the interchange on a daily basis; peak-hour capacity was expected to be reduced by 40 percent.

Temporary bridges and roadways were constructed to ensure that two lanes of traffic are open to through-traffic movements during peak hours during the life of the project. Temporary system ramps also were constructed to accommodate the largest turning movements in the interchange. Although the temporary construction helped facilitate keeping some traffic from diverting, other lesser-used system ramps will be closed for as many as three years.

To fully understand the anticipated traffic diversions that would result from the reconstruction, WisDOT worked closely with the Southeast Wisconsin Regional Planning Commission (SEWRPC), which integrated the anticipated lane and ramp closures into its travel-demand model. During the construction staging engineering process, SEWRPC examined a number of construction staging alternatives to help the project team identify the staging sequence that minimized the impact to the local street system and the community as a whole.