http://hdl.handle.net/1957/28193 Sat, 18 May 2013 13:44:28 GMT 2013-05-18T13:44:28Z http://hdl.handle.net/1957/38556 Spatial identification and optimization of upland wetlands in agricultural watersheds Babbar-Sebens, Meghna; Barr, Robert C.; Tedesco, Lenore P.; Anderson, Milo Wetland ecosystems are considered as potential ecological solutions for increasing the capacity of watersheds to store runoff waters upstream, and thereby, decrease risk of downstream flooding. Especially in tile-drained agricultural landscapes, wetlands constructed to intercept these tiles can serve as storage basins for agricultural runoff, leading to both reduction in peak runoff flows and diminished transport of agricultural nutrients. The objective of this study was to develop a watershed-scale methodology for identifying potential sites for wetlands in a tile-drained landscape in the Midwestern USA, and for optimizing the spatial distribution of these wetlands for reductions in peak runoff flows. The benefits of this methodology is demonstrated by using it for selecting appropriate wetland restoration and/or creation sites in Eagle Creek Watershed (ECW), located 10 miles northwest of Indianapolis, IN, USA. Results show that a large number of potential sites could be identified (e.g., 2953 sites in ECW), and with a choice of effective wetland design parameters and with spatial optimization of their areas, locations, and drainage areas, it is possible to achieve significant peak flow reductions with fewer sites and smaller wetlands. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Thu, 24 Jan 2013 00:00:00 GMT http://hdl.handle.net/1957/38556 2013-01-24T00:00:00Z http://hdl.handle.net/1957/38021 Planning of a Secondary Road Network for Low-Speed Vehicles in Small or Medium-Sized City: Using Google Earth Jannat, Mafruhatul; Hunter-Zaworski, Katharine M. In response to the growing environmental concern, the use of low speed vehicles (LSVs) on public roadways is gradually increasing in recent years as a short-range alternative to fossil-fueled autos. Primarily designed for protected environments and gated communities, LSVs have a maximum speed limit of 25 mph and are not subjected to the same Federal Motor Vehicle Safety Standards required for regular passenger cars. This paper presents a comprehensive planning methodology for the development of a secondary low speed roadway network primarily intended for use by LSVs that can be applied to small or medium-sized cities with closely located activity spaces. Typically, small or medium sized cities have limited planning or construction resources, therefore the objective was to develop the low speed network based on the existing road system of the city, with minimal infrastructure modifications. The City’s Transportation Plan and public opinion on route preference were integrated with the road analysis tool of Google Earth to accomplish the network development process. Public involvement in the process through a survey provided valuable insight on users’ route choice behavior; whereas the roadway inventory by City’s Transportation Planning document and Google Earth helped to evaluate city’s actual transportation infrastructure and also helped to analyze the factors influencing LSV users’ route preference behavior. The developed low speed roadway network is expected to provide safe and efficient connectivity from neighborhood areas to major activity centers of the city by LSVs, while minimally affecting the safe operations of regular automobiles. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Transportation Research Board of the National Academies and can be found at: http://www.trb.org/Main/Blurbs/154702.aspx. Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/1957/38021 2012-01-01T00:00:00Z http://hdl.handle.net/1957/37457 A Systems Approach to Civil Engineering Decisions Rodriguez-Nikl, Tonatiuh; Brown, Colin B. While contemporary civil engineering projects are increasingly complex, the cognitive abilities of the decision maker remain limited. There is a conflict between the complexity that is required to describe a scenario with all its relevant properties and the limited number of ideas that can be included in rational considerations and decisions. A resolution requires the decision maker to construct a limited model that includes the most significant features. In this paper, a systems approach provides a general decision-making scheme that makes involvement in broadly based decisions accessible. This scheme is valid at all scales and in all classes of problems. This paper establishes a practical method for generating systems that contain all features relevant to a professional decision. The criterion of decision invariance is offered as a guide for establishing the size of the system model considered by the decision maker. It is argued that surprises cannot be avoided and must form an integral part of the decision. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://ascelibrary.org/journal/jpepe3. Mon, 01 Oct 2012 00:00:00 GMT http://hdl.handle.net/1957/37457 2012-10-01T00:00:00Z http://hdl.handle.net/1957/37090 Assessment of Sign Retroreflectivity Compliance for the Development of a Management Plan Evans, Travis; Heaslip, Kevin; Boggs, Wesley; Hurwitz, David; Gardiner, Kevin The Manual on Uniform Traffic Control Devices (MUTCD) specifies minimum retroreflectivity requirements that include an obligation for agencies to develop a strategy for maintaining compliance. States were given a deadline of January 1, 2012 for the implementation of an assessment or management plan, which led to an increased emphasis on sign asset management. However, a new rule was submitted to the federal register to extend and modify the deadlines. With budget considerations it is important that a transportation agency implement an assessment or management plan that is efficient and provides compliance with the standards required by the Manual on Uniform Traffic Control Devices (MUTCD). The development of an efficient plan requires knowledge of the overall condition of an agency's assets as well as unique considerations regarding their performance. Through a review of previous data collection efforts, this paper details the development of a data collection strategy for assessing the performance of traffic signs maintained by the Utah Department of Transportation (UDOT). Agency operations, site selection, and attribute collection were all considered while developing a collection plan for an agency where limited inventory and installation data was available. Retroreflectivity measurements were taken for 1,433 UDOT signs. This sample provided a snapshot of current compliance and assisted in the selection of an asset management plan for maintaining sign retroreflectivity. Results from the study showed that UDOT’s signs were well over 90% compliant to the MUTCD standards and preliminary management strategies were presented to address vandalism and other damage. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Transportation Research Board of the National Academies and can be found at: http://www.trb.org/Main/Blurbs/154702.aspx. Fri, 12 Oct 2012 00:00:00 GMT http://hdl.handle.net/1957/37090 2012-10-12T00:00:00Z