Matching Items (5)

150192-Thumbnail Image.png

Energy use and greenhouse gas emissions In residential neighborhoods in the Southwest: a built environment life-cycle assessment

Description

In recent years environmental life-cycle assessments (LCA) have been increasingly used to support planning and development of sustainable infrastructure. This study demonstrates the application of LCA to estimate embedded energy use and greenhouse gas (GHG) emissions related to materials manufacturing

In recent years environmental life-cycle assessments (LCA) have been increasingly used to support planning and development of sustainable infrastructure. This study demonstrates the application of LCA to estimate embedded energy use and greenhouse gas (GHG) emissions related to materials manufacturing and construction processes for low and high density single-family neighborhoods typically found in the Southwest. The LCA analysis presented in this study includes the assessment of more than 8,500 single family detached units, and 130 miles of related roadway infrastructure. The study estimates embedded and GHG emissions as a function of building size (1,500 - 3000 square feet), number of stories (1 or 2), and exterior wall material composition (stucco, brick, block, wood), roof material composition (clay tile, cement tile, asphalt shingles, built up), and as a function of roadway typology per mile (asphalt local residential roads, collectors, arterials). While a hybrid economic input-out life-cycle assessment is applied to estimate the energy and GHG emissions impacts of the residential units, the PaLATE tool is applied to determine the environmental effects of pavements and roads. The results indicate that low density single family neighborhoods are 2 - 2.5 X more energy and GHG intensive, per residential dwelling (unit) built, than high density residential neighborhoods. This relationship holds regardless of whether the functional unit is per acre or per capita. The results also indicate that a typical low density neighborhood (less than 2 dwellings per acre) requires 78 percent more energy and resource in roadway infrastructure per residential unit than a traditional small lot high density (more than 6 dwelling per acre). Also, this study shows that new master planned communities tend to be more energy intensive than traditional non master planned residential developments.

Contributors

Agent

Created

Date Created
2011

150888-Thumbnail Image.png

Measuring the success of a transportation project: Loop 202 (Red Mountain Freeway) case study

Description

Measuring the success of a transportation project as it is envisioned in the Regional Transportation Plan (RTP) and is detailed in an Environmental Impact Statement (EIS) is not part of any current planning process, for a post construction analysis may

Measuring the success of a transportation project as it is envisioned in the Regional Transportation Plan (RTP) and is detailed in an Environmental Impact Statement (EIS) is not part of any current planning process, for a post construction analysis may have political consequences for the project participants, would incur additional costs, and may be difficult to define in terms of scope. With local, state and federal budgets shrinking, funding sources are demanding that the performance of a project be evaluated and project stakeholders be held accountable. The Transportation Research Board (TRB) developed a framework that allows transportation agencies to customize their reporting so that a project's performance can be measured. In the case of the Red Mountain Freeway, the selected performance measure allows for comparing the population forecasts, the traffic volumes, and the project costs defined in the final EIS to actual population growth, actual average annual daily traffic (ADT), and actual project costs obtained from census data, the City of Mesa, and contractor bids, respectively. The results show that population projections for both Maricopa County and the City of Mesa are within less than half a percent of the actual annual population growth. The traffic analysis proved more difficult due to inconsistencies within the EIS documents, variations in the local arterials used to produce traffic volume, and in the projection time-spans. The comparison for the total increase in traffic volume generated a difference of 11.34 percent and 89.30 percent. An adjusted traffic volume equal to all local arterials and US 60 resulted in a difference of 40 percent between the projected and actual ADT values. As for the project cost comparison, not only were the costs within the individual documents inconsistent, but they were underestimated by as much as 75 percent. Evaluating the goals as described in an EIS document using the performance measure guidelines provided by the TRB may provide the tool that can help promote conflict resolution for political issues that arise, streamline the planning process, and measure the performance of the transportation system, so that lessons learned can be applied to future projects.

Contributors

Agent

Created

Date Created
2012

149653-Thumbnail Image.png

Make straight in the desert a highway: ideology and environmental conflict on the Colorado Plateau

Description

In the rural, modern American West, two Manichean perspectives of the human-nature relationship have contributed to vehement environmental conflicts. Adopting developer Calvin Black and writer Edward Abbey as archetypes, I explore the endurance of these two ideologies in the redrock

In the rural, modern American West, two Manichean perspectives of the human-nature relationship have contributed to vehement environmental conflicts. Adopting developer Calvin Black and writer Edward Abbey as archetypes, I explore the endurance of these two ideologies in the redrock canyon country of southern Utah and northern Arizona. Black represents the historically dominant anthropocentric view among Euro Americans that nature ought to be domesticated and commoditized; the competing view, represented by Abbey, is eco-centric and considers the intrinsic value of the broader ecological community beyond its utilitarian function. I argue that environmental conflict in the canyon country has been driven by ideologues who espouse one of these two deeply entrenched and seemingly irreconcilable perspectives. Modern-day conflicts over wilderness, land use, and rural development are endemic, rooted in heritage and culture and driven by particular Anglo-American religious and secular beliefs that reflect differing ways of “seeing” the land. In particular these contending perspectives are reflected in the “built” landscape. Using one especially ubiquitous human imprint on the land as both trope and subject, I explore the political and cultural meanings of roads as symbols variously of progress and of exploitation. Questions of road development and public lands access became the center point of environmental conflict driven by dichotomous worldviews that demonized the opposition and its position. What developed in the last half century is a discourse dictated by categories created by ideologues. This dissertation not only explores the particular circumstances that made these environmental contests volatile in an American desert, but it also meditates broadly on the nature of environmental compromise and conflict, the place of people in "wild" landscapes, and the discontents of rural communities upended by new economic realities. This study illustrates generally how people perceive the land, the technology they wield to manipulate it, and the broader cultural and political transformations that result.

Contributors

Agent

Created

Date Created
2011

Life-Cycle Greenhouse Gas Emissions and Costs of the Deployment of the Los Angeles Roadway Network

Description

An inter-temporal life cycle cost and greenhouse gas emissions assessment of the Los Angeles roadway network is developed to identify how construction decisions lead to embedded impacts and create an emergent behavior (vehicle miles traveled by users) in the long

An inter-temporal life cycle cost and greenhouse gas emissions assessment of the Los Angeles roadway network is developed to identify how construction decisions lead to embedded impacts and create an emergent behavior (vehicle miles traveled by users) in the long run.

A video of the growth of the network and additional information are available here.

Contributors

Created

Date Created
2013-04

155142-Thumbnail Image.png

Flashing yellow arrow traffic signal operation: a clinical methodology for field conversion

Description

ABSTRACT

This study examines the methodology for converting protected, permissive, and protected/permissive left-turn operation to flashing yellow arrow left-turn operation. This study addresses construction-related considerations, including negative offsets, lateral traffic signal head position, left-turn accident rates, crash modification factors and crash

ABSTRACT

This study examines the methodology for converting protected, permissive, and protected/permissive left-turn operation to flashing yellow arrow left-turn operation. This study addresses construction-related considerations, including negative offsets, lateral traffic signal head position, left-turn accident rates, crash modification factors and crash reductions factors. A total of 85 intersections in Glendale, Arizona were chosen for this study. These intersections included 45 “arterial to arterial” intersections (a major road intersecting with a major road) and 40 “arterial to collector” intersections (a major road intersecting with a minor road).

This thesis is a clinical study of the field conversion to flashing yellow arrow traffic signals and is not a study of the merits of flashing yellow arrow operation. This study included six categories: 1. High accident intersections (for inclusion in Highway Safety Improvement Program (HSIP) funding); 2. Signal head modifications only; 3. Signal head replacement with median modifications; 4. Signal head and mast arm replacement; 5. Signal head, signal pole and mast arm replacement; and 6. Intersections where flashing yellow arrow operation is not recommended. Compliance with the Manual on Uniform Traffic Control Devices (MUTCD) played a large part in determining conversion costs because the standard for lateral position of the left-turn traffic signal greatly influenced the construction effort. Additionally, the left-turning vehicle’s sight distance factored into cost considerations. It’s important for agencies to utilize this study to understand all of the financial commitments and construction requirements for conversion to flashing yellow arrow operation, and ultimately to appreciate that the process is not purely a matter of swapping traffic signal heads.

Contributors

Agent

Created

Date Created
2016