Plazak’s scientific contributions

Urban and suburban roadways serve two distinct and sometimes conflicting purposes: providing mobility and allowing access to land and land developments. High-level urban roadways (e.g. arterials) should primarily serve mobility needs of travellers and goods. Low level, local roadways should primarily allow for land development access. Arterials that allow too much direct land access fail to function properly in terms of both traffic operations and safety. Such roadways are in need of access management. The operational and safety benefits of access management are impressive; access management has been shown to reduce crash rates on urban and suburban arterials by up to 40 to 50 percent. Identification of access management problem corridors (or corridors with excellent crash reduction potential) can be done in several ways. Physical features inconsistent with good access management practices can be identified. Alternatively, crash records can be used to identify outbreaks of crash types associated with poor access management. Ideally, both approaches may be used together. This paper will highlight four examples from the State of Iowa in the United States of the use of remote sensing imagery to extract access features and crash records to identify corridors with the most promise for improving safety through better access management. All four of these research studies are now being used by the Iowa Department of Transportation and/or metropolitan planning organizations in Iowa to improve the safety and operational performance of their urban arterials and other major roadways. Applications discussed in this paper include using remote sensing for estimating the level of access management, high priority commuting corridor identification the state of Iowa, regional access management planning for the Des Moines, Iowa USA metropolitan area, and the use of remote sensing for land use change detection and traffic monitoring. Keywords: access management, GIS, remote sensing, highway and road safety, land use.

515) 233-7300 Fax: (515) 233-7499 E-mail: Jamie.Luedtke@fhwa.dot.gov Abstract The safety benefits of access management, the controlling of access points on roadways, have been proven and have been well documented in past research. However, there is limited research on the economic impacts of access management, and most existing research is qualitative. Further quantitative research is needed because commercial business owners believing that direct and complete access to their land is an integral part of sales do not always accept access management practices. However, using sales data as an economic indicator in analysis presents problems, for sales data cannot be gathered per land parcel. Commercial land values are useful in this regard. This research measures the urban commercial land value impacts of access management applications in Des Moines, Iowa through a regression model. The regression model is based on the hedonic property value model, a regression model measuring relationships between non-market variables and property values. The regression model used in this study measures relationships between commercial land values per square foot to parcel square footage, average annual daily traffic (AADT) counts, and scaled access control for each study parcel. The results of the study regression model found that both parcel square footage and AADT have negative relationships to commercial land values, while access control has virtually no influence on commercial land values. This finding could help demonstrate to business owners that access control should not negatively impact their land values, and be one step to further access management acceptance in the business community.