A Multiobjective Optimization Approach to Smart Growth in Land Development
Authors: Steven A. Gabriel, Jose A. Faria, and Glenn E. Moglen (2010)
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Synopsis: In this paper we describe a multiobjective optimization model of "Smart Growth" applied to land development in Montgomery County, Maryland. The term "Smart Growth" is generally meant to describe those land development strategies which do not result in urban sprawl, however the term is somewhat open to interpretation. The multiobjective aspects arise when considering the conflicting interests of the various stakeholders involved: the government planner, the environmentalist, the conservationist, and the land developer. We present a formulation, which employs linear and convex quadratic objective functions for the stakeholders that are subject to polyhedral and binary constraints. As such, the resulting optimization problems are convex, quadratic mixed integer programs which are known to be NP-complete (Mansini and Speranza, 1999). We report numerical results with this model and present these results using a geographic information system (GIS).
Authors: Glenn Moglen, Karen Nelson, Margaret Palmer, et al. (2005)
Report
Synopsis: Urbanization in the Chesapeake Bay watershed is having dramatic impacts on the streams and rivers that feed the Bay. Increasing imperviousness has led to higher peak flows and lower base flows. The movement of pollutants and other materials to receiving waters has increased and stream water temperatures have risen. These changes alter the structure and functioning of reivers, streams, and associated riparian corridors and result in changes in ecosystem services.We define a hydrologic disturbance index that indicates varying degrees of disturbance on a reach-by-reach basis, dependent on the aggregate amount of urbanization upstream of each reach. For current conditions this index is more variable than for future conditions, because current land use in the study watershed is more variable, containing mixtures of urban, agricultural, and forested land. In contrast, future land use is projected to be more uniformly urban, leading to a less variable but greater overall degree of hydrologic disturbance.Two effects of urbanization on fish are explored through ecological modeling: effects of streambed disturbance on food availability and effects of stream temperature on spawning. We tabulate food availability as a function of bed-mobility for 30 different fish species. We show that additional stress occurs with additional urbanization of the watershed. We show that the urban-related increase in stream temperatures may cause several warm-water species to gain opportunities to spawn in some cases. However, combining food availability and spawning day availability into a single index reveals highly stressful conditions for all fish species under the fully developed scenario.
Authors: Glenn Moglen, Steven Gabriel, and Jose Faria (2003)
Report
Synopsis: Increasing awareness about the problems brought on by urban sprawl has led to proactive measures to guide future development. Such efforts have largely been grouped under the term, Smart Growth. Although not widely recognized as such, the smart in Smart Growth implies an optimization of some quantity or objective while undertaking new forms of urban development. To illustrate a formal, quantitative framework for Smart Growth, this study develops definitions of optimal development from the perspectives of four different types of stakeholders: a government planner, a land developer, a hydrologist, and a conservationist subject to certain developmental constraints. Four different objective functions are posed that are consistent with each of these stakeholders’ perspectives. We illustrate the differences in consequences on future development given these different objective functions in a stylized representation for Montgomery County, Maryland. Solutions to Smart Growth from the individual perspectives vary considerably. Trade-off tables are presented which illustrate the consequences experienced by each stakeholder depending on the viewpoint that has been optimized. Although couched in the context of an illustrative example, this study emphasizes the need to apply rigorous, quantitative tools in a meaningful framework to address Smart Growth. The result is a tool that a range of parties can use to plan future development in ways that are environmentally and fiscally responsible and economically viable.
Authors: Glenn Moglen (2005)
Report
Synopsis: This paper presents a GIS-based program called GISHydro2000. This tool was developed by the author and is used extensively by state government and private consultants in the development of predictions for flood behavior in the state of Maryland. This paper presents a demonstration of the program’s overall functionality and underlying spatial database. An actual example watershed will be analyzed to illustrate how GISHydro2000 works and the tools it provides.
Authors: Steven A. Gabriel, Jose A. Faria, and Glenn E. Moglen (2010)
Report
Synopsis: In this paper we describe a multiobjective optimization model of "Smart Growth" applied to land development in Montgomery County, Maryland. The term "Smart Growth" is generally meant to describe those land development strategies which do not result in urban sprawl, however the term is somewhat open to interpretation. The multiobjective aspects arise when considering the conflicting interests of the various stakeholders involved: the government planner, the environmentalist, the conservationist, and the land developer. We present a formulation, which employs linear and convex quadratic objective functions for the stakeholders that are subject to polyhedral and binary constraints. As such, the resulting optimization problems are convex, quadratic mixed integer programs which are known to be NP-complete (Mansini and Speranza, 1999). We report numerical results with this model and present these results using a geographic information system (GIS).
Hydro-Ecologic Responses to Land Use in Small Urbanizing Watersheds Within the Chesapeake Bay Watershed
Authors: Glenn Moglen, Karen Nelson, Margaret Palmer, et al. (2005)
Report
Synopsis: Urbanization in the Chesapeake Bay watershed is having dramatic impacts on the streams and rivers that feed the Bay. Increasing imperviousness has led to higher peak flows and lower base flows. The movement of pollutants and other materials to receiving waters has increased and stream water temperatures have risen. These changes alter the structure and functioning of reivers, streams, and associated riparian corridors and result in changes in ecosystem services.We define a hydrologic disturbance index that indicates varying degrees of disturbance on a reach-by-reach basis, dependent on the aggregate amount of urbanization upstream of each reach. For current conditions this index is more variable than for future conditions, because current land use in the study watershed is more variable, containing mixtures of urban, agricultural, and forested land. In contrast, future land use is projected to be more uniformly urban, leading to a less variable but greater overall degree of hydrologic disturbance.Two effects of urbanization on fish are explored through ecological modeling: effects of streambed disturbance on food availability and effects of stream temperature on spawning. We tabulate food availability as a function of bed-mobility for 30 different fish species. We show that additional stress occurs with additional urbanization of the watershed. We show that the urban-related increase in stream temperatures may cause several warm-water species to gain opportunities to spawn in some cases. However, combining food availability and spawning day availability into a single index reveals highly stressful conditions for all fish species under the fully developed scenario.
A Framework for Quantitative Smart Growth in Land Development
Authors: Glenn Moglen, Steven Gabriel, and Jose Faria (2003)
Report
Synopsis: Increasing awareness about the problems brought on by urban sprawl has led to proactive measures to guide future development. Such efforts have largely been grouped under the term, Smart Growth. Although not widely recognized as such, the smart in Smart Growth implies an optimization of some quantity or objective while undertaking new forms of urban development. To illustrate a formal, quantitative framework for Smart Growth, this study develops definitions of optimal development from the perspectives of four different types of stakeholders: a government planner, a land developer, a hydrologist, and a conservationist subject to certain developmental constraints. Four different objective functions are posed that are consistent with each of these stakeholders’ perspectives. We illustrate the differences in consequences on future development given these different objective functions in a stylized representation for Montgomery County, Maryland. Solutions to Smart Growth from the individual perspectives vary considerably. Trade-off tables are presented which illustrate the consequences experienced by each stakeholder depending on the viewpoint that has been optimized. Although couched in the context of an illustrative example, this study emphasizes the need to apply rigorous, quantitative tools in a meaningful framework to address Smart Growth. The result is a tool that a range of parties can use to plan future development in ways that are environmentally and fiscally responsible and economically viable.
GISHydro2000: A Tool for Automated Hydrologic Analysis in Maryland
Authors: Glenn Moglen (2005)
Report
Synopsis: This paper presents a GIS-based program called GISHydro2000. This tool was developed by the author and is used extensively by state government and private consultants in the development of predictions for flood behavior in the state of Maryland. This paper presents a demonstration of the program’s overall functionality and underlying spatial database. An actual example watershed will be analyzed to illustrate how GISHydro2000 works and the tools it provides.