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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Analysis of Best Management Practices for Addressing Urban Stormwater Runoff

Maass, Amanda January 2016 (has links)
Sustainable Built Environments Senior Capstone Project / During Tucson rainstorms, many roads and neighborhoods experience high levels of flooding on the city’s street networks. This phenomenon creates unsafe road conditions, damage to the road infrastructure, and excessive urban stormwater runoff that is potentially polluted. The vast quantities of impervious surfaces in the urban landscape impede the rainwater’s ability to infiltrate the ground, thus resulting in increased volumes of runoff during a rainstorm. Stormwater management is used by municipalities and communities to address the previously mentioned adverse impacts of stormwater runoff. Various techniques and strategies used in stormwater management include, low impact development (LID), green infrastructure, and better site design (BSD) strategies implemented during design stages to reduce stormwater runoff levels. In addition, local governments can establish stormwater utilities and policies in order to help address and better manage the issue of stormwater runoff within urban areas. The primary research questions of this study will include: What are the most effective best management practices and techniques to address urban runoff? What combination of best management practices and government policies will be the more effective in addressing Tucson’s urban runoff problem? Accordingly, this study will examine a variety of policies and techniques to address stormwater runoff, and then, based on this information, provide a suggestion of the best practices and techniques that may be feasible for implementation in Tucson.
32

EVALUATING STREAMSIDE MANAGEMENT ZONE EFFECTIVENESS IN FORESTED WATERSHEDS OF THE CUMBERLAND PLATEAU

Witt, Emma Lela 01 January 2012 (has links)
Headwater stream systems are important components of the overall hydrologic system. Forestry best management practices (BMP) are effective at minimizing non point source pollution from forest harvesting activities. Streamside management zones (SMZ) are one BMP used to protect surface water quality by maintaining shade near streams, filtering runoff, and minimizing soil disturbance near streams. An evaluation of BMP effectiveness on the watershed scale was conducted at the University of Kentucky’s Robinson Forest. Six watersheds were harvested using a two-age deferment harvest with one of three SMZ configurations applied to each watershed. Two unharvested watersheds served as controls. Treatment 1 was based on the current Kentucky Forest Practice Guidelines for Water Quality Management and included a 16.8 m SMZ with 50% canopy retention for perennial streams, a 7.6 m SMZ with no canopy retention for intermittent streams, and no SMZ or canopy retention for ephemeral streams with unimproved crossings. Treatment 2 also included a 16.8 m perennial SMZ but increased canopy retention to 100%, as well as a 7.6 m intermittent SMZ with 25% canopy retention, and retention of channel bank trees and use of improved crossings for ephemeral streams. Treatment 3 required a 33.5 m perennial SMZ with 100% canopy retention, a 16.8 intermittent SMZ with 25% canopy retention, and a 7.6 m ephemeral SMZ with retention of channel bank trees and use of improved crossings. Total suspended solids (TSS) concentration and turbidity was measured in storm samples in perennial and ephemeral streams, and in non-storm samples in perennial and intermittent streams. Nitrate-N, ammonium-N, and dissolved oxygen concentrations were also measured in non-storm samples in perennial and intermittent streams. Temperature and water level were recorded every 15 minutes for the duration of the study. Results showed that treatment 3 was able to maintain TSS concentrations and turbidity levels similar to those measured in unharvested control watersheds. Increases in nitrate-N and mean daily temperature were measured for all treatments. Ammonium-N and dissolved oxygen concentrations were not different from unharvested control watersheds for any treatment. Storm hydrograph separation did not result in consistent changes post-harvest for any treatment.
33

Rethinking rainfall: exploring opportunities for sustainable stormwater management practices in Turkey Creek Basin and downtown Kansas City

Ptomey, Patrick January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Timothy Keane / Kansas City’s outdated sewer system is presently incapable of capturing and treating the increased runoff volumes in Turkey Creek Basin during rainstorm events. As a result, 2.66 billion gallons of untreated sewer system overflow is released annually into the Kansas River and nearby properties. In 2002, the Environmental Protection Agency issued a civil action requiring the City of Kansas City, Missouri, to take appropriate and necessary actions needed to prevent or minimize the discharge of untreated sewage. In response, the City of Kansas City adopted a comprehensive Overflow Control Plan intended to reduce sewer system overflow volumes in Turkey Creek Basin by 85% at a cost of approximately $244 million. Initially, the City of Kansas City seriously considered implementing stormwater best management practices (BMPs) in place of sewer system improvements. Stormwater BMPs infiltrate, filter, store, and evaporate stormwater runoff close to its source, preventing stormwater runoff from reaching the sewer system. Subsequently, many BMPs were eliminated from the Overflow Control Plan and replaced with conventional sewer system technologies because of performance concerns. However, the Overflow Control Plan acknowledged that BMPs located on private property would indirectly benefit Kansas City’s stormwater management strategy. Using geographic information system (GIS) analysis, suitability maps were generated for twelve different BMPs to determine suitable locations in Turkey Creek Basin for reducing stormwater runoff. Analysis concluded that the most effective strategy for sustainable stormwater management would be to locate BMPs at higher elevations within the watershed to prevent upland runoff from flooding sewer system pipes at lower elevations. Areas having the highest suitability are located primarily on residential land, implying that Kansas City could benefit most from encouraging its residents to equip their properties with site-appropriate BMPs. This can be achieved through educational initiatives, policy adoption, and homeowner incentives. Therefore, policies and incentives targeting Kansas City’s residents should be implemented to reduce sewer overflow volumes and prevent future costly improvements to Kansas City’s sewer system.
34

Burning bridges, reinventing the American lawn: a strategic approach to residential stormwater management

Sanders, Christopher L. January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Timothy Keane / Wildcat Creek watershed in Riley County, Kansas has been scene to increasingly severe and damaging flooding in recent years. Significant flood events in the summer of 2010 and 2011 have prompted the community to action. One of many areas of concern is addressed by this project in order to facilitate community efforts to reduce future flooding. Residential stormwater best management practices (BMPs) implemented by property owners to reduce the amount of stormwater runoff entering the Wildcat Creek watershed is the focus of this project. An analysis of the residential development typology in the City of Manhattan within the Wildcat Creek watershed guides stormwater BMP implementation strategies. GIS identified residential development types based on land use, land cover, and parcel size. Single family residential and high density multi-family developments are the areas of focus. Rational method stormwater calculations were conducted on one sample site selected from each of four areas identified as unique within the residential context. The four sample sites include large lot single family, small lot single family, traditional single family, and high density multi-family. The current stormwater runoff situation was constructed for residential areas of Manhattan within the Wildcat Creek watershed using these samples. Sample sites were evaluated four times. Existing stormwater runoff amounts for each site were determined. A minimal BMP treatment in the form of rain gardens was applied. Then a moderate BMP treatment including rain gardens, rain barrels, and native plantings was applied. The fourth evaluation was on a high level of rainwater BMP treatment including rain gardens, rain barrels, cisterns, native vegetation, bioretention, and permeable paving. Post-BMP runoff calculations were performed. The resulting data was compared to the pre-BMP stormwater data to determine the impact of varying degrees of BMP treatments. This work produced a series of BMP strategies specifically suited to the Wildcat Creek watershed. These site specific strategies are a valuable resource for community members to help reduce flooding in the watershed. The resulting calculations are also valuable tools for community leaders determining the value of stormwater regulations that may require or promote stormwater BMPs in Manhattan.
35

A hydrologic approach to environmental golf and hazard design within the Wildcat Creek Watershed

Clark, Jeffrey January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Timothy Keane / The City of Manhattan, Kansas is looking for possible solutions to mitigate flooding along Wildcat Creek within the Wildcat Creek Watershed. Recent flooding has caused substantial property damage. The project presented here brings recreation into the community by designing a golf course in a location along Wildcat Creek that addresses flooding issues, increases infiltration, and improves water quality. The golf industry has a long way to go to become more sustainable. The world is facing many challenges related to water and hydrology. Much of the opposition towards the golf industry is because critics see it as environmentally unfriendly. Golf has the potential to become a catalyst for change in the way we design and develop the landscape around us. The golf industry can become a leader in sustainable design while taking on hydrological concerns within the community. This project demonstrates the application of a golf course to help mitigate flooding along Wildcat Creek with the use of vulnerability and suitability analysis as a guide to site selection. This method of analysis illustrates the process of identifying and protecting areas vulnerable to degradation by designing a golf course in a suitable location to utilize water hazards to store flood water, provide more floodplain access to effectively increase infiltration capacity, reduce runoff rates, and improve water quality. The report explains the relationship between golf course design and environmental practices as they relate to hydrology on a theoretical site in Manhattan, Kansas. By integrating golf course design theory and environmentally sound stormwater management practices, water hazards on the golf course can become the fundamental elements used in strategizing the design of the golf course. A conceptual plan was created to maximize the infiltration capacity of the site as well as allow increased floodplain access, and provide a place to store flood water. A golf course can then be properly sited and designed hydrologically around the use of water hazards to help reduce flooding and improve water quality within the watershed.
36

Communicating towards resiliency: identifying the barriers and social constraints related to grazing best management practices in Kansas and Oklahoma

King, Audrey E. H. January 1900 (has links)
Master of Science - Agricultural Education and Communication / Department of Communications and Agricultural Education / Lauri M. Baker / Kansas and Oklahoma were in the top five cattle producing states in the United States. Beef cattle producers across Kansas and Oklahoma had access to best management practices (BMPs) for proper grazing land management, but were still underutilizing these practices. This study sought to understand why producers did not adopt grazing BMPs suggested by Extension professionals and to identify opportunities to improve communication and adoption. Under the postulates of elaboration likelihood model (ELM), if BMPs were communicated to producers in a way that persuaded them to adopt BMPs, the resiliency of the entire beef cattle grazing system, would increase. This study was guided by community-based social marketing (CBSM) and elaboration likelihood model (ELM). Semi-structured qualitative interviews were conducted with 43 producers in north central Oklahoma and south central Kansas during the summer of 2015. Initial participants were recruited using a purposive sampling method through Extension contacts with a snowball sample after initial participants were identified. Interviews were transcribed by a professional transcription service and analyzed using Glaser’s constant comparative method. Producers in the study were aware of BMPs like rotational grazing, prescribed burning, and the usage of alternative forages. The major themes discovered in this study include Producers had varying definitions of both rotational grazing and cover crops; Producers used each other, Extension and university materials and personnel as information sources; Practices producers used were determined by visual observations and past experiences. Barriers and social constrains to the adoption of BMPs that were discovered included: water availability and quality, land leases, time and labor, land lords, generational gaps, and a lack of skilled employees. Producers saw the benefits of burning practices and rotational grazing. Another major theme was drought tested the resiliency of producer’s operations. This study offers several recommendations for Extension professionals and research. The way that Extension agents were communicating BMPs should be researched and analyzed. The implementation of CBSM and ELM by Extension professionals could increase the adoption of BMPs in grazing systems. A major implication of this study was the need for Extension to more openly communicate with producers rather than just exchange information.
37

Mitigating Gaseous Nitrogen and Carbon Losses from Northeastern Agricultural Soils via Alternative Soil Management Practices

Dittmer, Kyle Michael 01 January 2019 (has links)
Traditional agricultural practices often result in gaseous losses of nitrous oxide (N2O), ammonia (NH3), and carbon dioxide (CO2), representing a net loss of nutrients from agricultural soils, which negatively impacts crop yield and requires farmers to increase nutrient inputs. By adopting best management practices (BMPs; i.e., no-tillage, cover crops, sub-surface manure application, and proper manure application timing), there is great potential to reduce these losses. Because N2O and CO2 are also greenhouse gases (GHGs), climate change mitigation via BMP adoption and emissions reductions would be an important co-benefit. However, adopting a no-tillage and cover cropping system has had setbacks within the Northeast, primarily due to concerns regarding manure nitrogen (N) losses in no-tillage systems as well as uncertainty surrounding the benefits of cover crops. This thesis used two field-trials located in Alburgh, Vermont to assess differences in (i) GHG emissions from agricultural soils, (ii) nitrate and ammonium retention, (iii) corn yield and protein content, and (iv) N uptake and retention via cover crop scavenging under a combination of different BMPs. Chapter 1 evaluates the effects of different reduced-tillage practices and manure application methods (i.e., vertical-tillage, no-tillage, manure injection, and broadcast manure application) on reducing N2O and CO2 emissions, retaining inorganic N, and improving crop yields. Greenhouse gas measurements were collected every other week for the growing season of 2015-2017 via static chamber method using a photoacoustic gas analyzer. Results from this study showed that tillage regimes and manure application method did not interact to affect any of the three research objectives, although differences between individual BMPs were observed. Notably, vertical tillage enhanced CO2 emissions relative to no-tillage, demonstrating the role of soil disturbance and aeration on aerobic microbial C transformations. Manure injection was found to significantly enhance both N2O and CO2 emission relative to broadcast application, likely due to the formation of anerobic micro-zones created from liquid manure injection. However, plots that received manure injection retained greater concentrations of soil nitrate, a vital nutrient for quality crop production, thereby highlighting a major tradeoff between gaseous N losses and N retention with manure injection. Chapter 2 evaluates the effects of tillage practices and timing of manure application to increase N retention with the use of cover crops in order to mitigate GHG emissions, enhance soil nitrate and ammonium retention, and improve cropping system N uptake. Treatments at this field trial consisted of a combination of the presence or absence of cover crops, no-tillage or conventional-tillage, and spring or fall manure application. Greenhouse gas emissions were measured every other week via static chamber method using a gas chromatograph for the growing season of 2018. Results from this study showed that the presence of cover crops enhanced both N2O and CO2 emissions relative to fallow land, irrespective of tillage regime and manure application season, likely as a result of greater N and carbon substrates entering the soil upon cover crop decomposition. Due to enhanced N2O emissions with cover crops, cover crops did not retain significantly greater inorganic N in the system upon termination.
38

Evaluation of compost specifications for stormwater management

Birt, Lindsay Nicole 15 May 2009 (has links)
Urban development will continue to increase in Texas because of population growth and urban sprawl. Despite the desire for urbanization and expansion of the economy, this growth increases the amount of construction, which, if not properly managed, can increase non-point source pollution and threaten surface water quality. Therefore, Texas Department of Transportation (TxDOT) has approved and promoted the use of compost as a stormwater best management practice (BMP) during highway construction. The objectives of this study were to construct and calibrate an indoor rainfall simulator and to determine the effectiveness of using compost rather than conventional hydroseeding or topsoil to reduce erosion from disturbed soils. Runoff rates, interrill erosion, and interrill erodibility were determined and compared across five compost treatments following TxDOT specifications for compost applied as an erosion control and two control treatments of topsoil (TS) and hydroseeding (HS) applied at 5 cm depth. The simulator produced 89% uniformity using ten Veejet 80100 nozzles at a target rate of 100 mm h-1. The surface runoff was collected after 5 minutes of rainfall (first flush) and during the last 30 minutes of rainfall (steady-state). The first flush mean runoff for GUC-5 treatment was significantly higher than all other treatments. All other treatments; 50% woodchips and 50% compost blend (ECC-1.3, ECC-5), and hydroseeding (HS) had significantly lower runoff and erosion rates compared to topsoil (TS) and compost manufactured topsoil (CMT) at first flush and steady-state. Furthermore, there were no performance differences between 1.3 cm and 5 cm compost applications at first flush or steady-state. The results of this project indicate that particle size, soil moisture capabilities, and time at which rainfall is applied affect surface runoff. TxDOT specification of using ECC at 5 cm depth on a max of 3:1 slope should be reconsidered. An ECC application depth of 1.3 cm was effective in reducing first flush runoff and interrill erosion rates.
39

Evaluation of compost specifications for stormwater management

Birt, Lindsay Nicole 15 May 2009 (has links)
Urban development will continue to increase in Texas because of population growth and urban sprawl. Despite the desire for urbanization and expansion of the economy, this growth increases the amount of construction, which, if not properly managed, can increase non-point source pollution and threaten surface water quality. Therefore, Texas Department of Transportation (TxDOT) has approved and promoted the use of compost as a stormwater best management practice (BMP) during highway construction. The objectives of this study were to construct and calibrate an indoor rainfall simulator and to determine the effectiveness of using compost rather than conventional hydroseeding or topsoil to reduce erosion from disturbed soils. Runoff rates, interrill erosion, and interrill erodibility were determined and compared across five compost treatments following TxDOT specifications for compost applied as an erosion control and two control treatments of topsoil (TS) and hydroseeding (HS) applied at 5 cm depth. The simulator produced 89% uniformity using ten Veejet 80100 nozzles at a target rate of 100 mm h-1. The surface runoff was collected after 5 minutes of rainfall (first flush) and during the last 30 minutes of rainfall (steady-state). The first flush mean runoff for GUC-5 treatment was significantly higher than all other treatments. All other treatments; 50% woodchips and 50% compost blend (ECC-1.3, ECC-5), and hydroseeding (HS) had significantly lower runoff and erosion rates compared to topsoil (TS) and compost manufactured topsoil (CMT) at first flush and steady-state. Furthermore, there were no performance differences between 1.3 cm and 5 cm compost applications at first flush or steady-state. The results of this project indicate that particle size, soil moisture capabilities, and time at which rainfall is applied affect surface runoff. TxDOT specification of using ECC at 5 cm depth on a max of 3:1 slope should be reconsidered. An ECC application depth of 1.3 cm was effective in reducing first flush runoff and interrill erosion rates.
40

Development of a mult-objective strategic management approach to improve decisions for pavement management practices in local agencies

Chang 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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