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Development of a mult-objective strategic management approach to improve decisions for pavement management practices in local agenciesChang Albitres, Carlos Martin 15 May 2009 (has links)
Multiple objectives are often used by agencies trying to manage pavement networks.
Often alternative investment strategies can accomplish the agencies’ target objectives. If the
goal is to achieve the target objectives at the minimum cost, an approach is needed to assist
agencies in identifying investment strategies capable of meeting the targets while
minimizing costs.
The approach used by the agency should not be limited to an analytical method to
mathematically solve the funding allocation problem. Finding mechanisms to ensure the
sustainability and efficiency of the investment strategy over time is a great challenge that
needs to be addressed by the approach. The challenge is even greater for local agencies
where resources are usually limited.
This research develops a multi-objective strategic management approach oriented to
improving decisions for pavement management practices in local agencies. In this approach, target objectives are tied to key pavement network parameters in the management process.
A methodology to identify the best combination of projects to meet target objectives at the
minimum cost while maximizing treatment effectiveness is provided as a result of the
research.
Concepts from the pavement management program (PMP) of the Metropolitan
Transportation Commission (MTC) of the San Francisco Bay Area were used as a basis for
developing the methodology. Four pavement network parameters are considered for setting
the target objectives over the agency’s planning horizon: the average network pavement
condition index (PCI), average network remaining life, percent of the pavement network in
good condition, and percent of the pavement network in poor and very poor condition.
Results from a case study show that funding allocation methods influence the
allocation of preservation and rehabilitation funds among pavement network groups,
affecting budget estimates and future condition of the pavement network. It is also
concluded that the use of mechanisms that facilitate data integration and the flow of
knowledge across management levels can contribute to making better informed decisions.
Hence, the adoption of the multi-objective strategic pavement management approach
developed in this dissertation should lead to identifying more efficient investment strategies
for achieving the pavement network state desired by a local agency at a minimum cost.
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Simulating and Optimizing Storm Water Management Strategies in an Urban WatershedDamodaram, Chandana 2010 December 1900 (has links)
Land development transforms the natural landscape and impacts in stream ecosystems and downstream communities as it alters the natural flow regime. An increase in impervious areas results in higher volumes of storm water runoff, reduced time to peak, and more frequent flooding. Best Management Practices (BMP) and Low Impact development (LID) are a few of the set of measures which are used to mitigate the impact of urbanization. Peak flow, runoff volume are few of the conventional metrics which are used to evaluate the impact and performance of these storm water management strategies on the watershed. BMP are majorly used to control the flood runoff but results in the release of large volumes of runoff even after the flood wave passed the reach and LIDs are used to replicate the natural flow regime by controlling the runoff at the source. Therefore need to incorporate a metric which includes the timing and area being inundated needs to be considered to study the impact of these strategies on the downstream.
My proposed research will focus on simulating the Low Impact Development (LID) techniques like permeable pavements and rainwater harvesting on an urbanized watershed using a curve number approach to quantify the hydrologic performance of these strategies on the watershed. LID, BMPs, and combined strategies are introduced for retrofitting existing conditions and their hydrologic performance is accessed based on the peak flow and a new metric Hydrologic Footprint Residence. A simulation optimization framework would be developed which identifies cost effective LID options that maximize the reduction of peak flow from the existing condition design storms while meeting budget restrictions. Further LID and BMP placement is included in the optimization model to study the impact of the combined scenario on the storm water management plans and their performance based on different storms and corresponding budget. Therefore a tradeoff can be illustrated between the implementation cost and the hydrological impact on the watershed based on the storm water management approach of using only LID and combination of LID and BMP corresponding to varied spectrum of design storm events.
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THE IMPACTS OF LOGGING WITH CURRENT AND MODIFIED BEST MANAGEMENT PRACTICES ON WATERSHED CHARACTERISTICS IN EASTERN KENTUCKYClark, Chase 01 January 2015 (has links)
In Kentucky, Best Management Practices (BMPs) were developed to protect the integrity of water resources during and after silvicultural operations, but their effectiveness is largely unknown. The study objectives were to (1) quantify the extent to which current BMPs minimized logging-related changes in stream water quality, channel morphology, and the content of woody debris and (2) quantify the extent to which modified BMPs influenced these characteristics. Six watersheds in eastern Kentucky were commercially logged in 2008-2009. In each watershed, one of three treatments was implemented (each replicated once). Treatment 1 (BMP) was based on current Kentucky BMPs. In treatments 2 (BMP+) and 3 (BMP++), current BMPs were modified with additional protective measures. Before the harvest, sampling sites were established in each watershed. Channel morphology and woody debris data were collected at each site in 2006 and again 2014. Data for water chemistry were retrieved from ongoing sampling records. BMP watersheds were compared to one another and to unharvested control watersheds in each year independently. Data within each individual watershed were also compared across years. The results indicate that current BMPs were effective in minimizing changes in the watershed characteristics examined here, and the benefits of modified BMPs were highly variable.
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IMPLEMENTATION COSTS OF KENTUCKY'S EROSION CONTROL BEST MANAGEMENT PRACTICES FOR SKID TRAILSShouse, Bennett Scott 01 January 2001 (has links)
This paper describes a study designed to determine average labor and machine times required to implement erosion control and revegetation best management practices (BMPs) for skid trails in Kentucky. Labor and machine activities were recorded for 14,400 feet of skid trail on 10 nonindustrial private logging sites. Water bar construction and reshaping activities such as filling ruts and berm removal were filmed continuously with a video camera and then analyzed using time-motion study techniques. Labor activities for revegetation such as seeding and application of fertilizer were also timed. The average total machine time for retirement activities per 1000 feet was 51 minutes for sites using dozers and 52 minutes for sites using skidders. The average water bar construction time using a bulldozer was 1.5 minutes (n=112) while the average construction time using a skidder was 3.5 minutes (n = 21). The average amount of labor time required to seed 1000 feet of skid trail was 23 minutes (n = 5). Three methods of water bar construction were observed and analyzed to identify differences among them. While there were significant differences among the three methods, the data suggest that skid trail percent slope may have the greatest effect on water bar construction times.
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Aquatic invertebrate-habitat relationships and stream channel cross section area change in response to streamside management zones in North Central Mississippi /Luecker, Terry A. January 2004 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 51-55). Also available on the World Wide Web.
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Examination, application, and evaluation of geomorphic principles and resulting water quality in Midwest agricultural streams and riversPowell, George Erick, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 139-141).
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Who's afraid of a little nitrate? : discovering impediments and incentives in following best management practices related to water quality within the southern Willamette Valley groundwater management area /Rolston, Irene. January 1900 (has links)
Thesis (M.A.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 91-99). Also available online.
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Developing best practice in environmental impact assessment using risk management ideas, concepts and principles : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Civil Engineering in the University of Canterbury /Fietje, Leo. January 2001 (has links)
Thesis (M.E.)--University of Canterbury, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 134-144). Also available via the World Wide Web.
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Reducing dental mercury discharge in Missoula, Montana collaborative opportunities /Silberberger, Jamie. January 2007 (has links)
"Professional paper presented in partial fulfillment of the requirements for the degree of Master of Science, Environmental Studies, the University of Montana, Missoula, MT, spring 2007." / Title from PDF title page (viewed on Aug. 12, 2007). Includes bibliographic references (p. 67-69).
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Determination of Polycyclic Aromatic Hydrocarbons (PAHS) resulting from wood storage and wood treatment facilities for electricity transmission in SwazilandVan Zuydam, Constance Sthembile 30 June 2007 (has links)
A study was conducted in two sites: one at an electricity storage facility belonging to
the Swaziland Electricity Board (SEB) and the other at a facility that belongs to its
treated pole supplier, the Thonkwane wood creosote treatment plant. The drainage
system of these sites leads to surface waters in rivers. This is a cause of concern
since creosote contains polycyclic aromatic hydrocarbons (PAHs), which are listed
as priority pollutants by the US Environmental Protection Agency. They have toxic,
mutagenic and carcinogenic effects and as a result they pose a threat to human life
and the environment. No previous studies have been done on PAHs in Swaziland.
The main objective of this study was to determine the impact of the SEB storage
facility and the creosote treatment plant by investigating the extent of PAHs in
surrounding environments (soil, sediments and surface waters).
Preliminary studies were undertaken on the storage facility and the creosote
treatment plant. No PAHs were detected from the pole storage facility; therefore the
creosote wood treatment facility was selected as the ideal site at which to conduct
the research. Soil samples were collected from depths 15 cm and 60 cm at points
around the creosote plant, including effluent discharge points. The samples were
extracted by solid-phase micro extraction (SPME) and analysed by GC/MS. The
GC/MS, incorporating a solid phase micro extraction step, provided detection limits
ranging from 0.12 μg/g to 20.08 μg/g. The pollution patterns in the study site were
assessed using cluster analysis and principal component analysis.
Most of the 16 US EPA-listed priority pollutants were detected from the creosote
wood treatment facility. PAHs such as anthracene, fluorene, naphthalene and
fluoranthene were dominant in all the sampling sites. The compounds occurred in
very high concentrations (0.64, 0.46, 0.27 and 0.26 mg/kg respectively). These
compounds are found in pure creosote as determined in the sample taken from the
Thonkwane creosote tank site. The highest concentration of PAHs was observed in
the soil samples taken next to the road site.
The concentrations of the identified PAHs were above the acceptable minimal level
allowed in soil by the US EPA and Swaziland Environment Authority (SEA). The
levels of the PAHs are also above the recommended US EPA limit in soil, which is
0.1 mg/kg. The results indicated that significant soil pollution was taking place in
some of the sampling sites.
The top layer (0, 15 cm) contained many PAHs at high levels whilst the 60 cm layer
had a lower number of PAHs which were also in low concentrations. This provided
an indication that there is no downward movement of PAHs from the surface layer to
underground layers. The potential exists for contamination of surface waters when
there is runoff from the project area. This is a cause of concern, since both the
creosote treatment plant and areas outside the facility are contaminated. Therefore,
the site has to be cleaned up, preferably by using a phytoremediation technique. / Environmental Sciences / M. Sc. (Environmental Science)
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