Global ETD Search

1	Evaluation of an Intensive Data Collection System for Tennessee Surface Water Quality Assessment and Watershed Model Calibration Armstrong, Hannah Marie 01 August 2011 (has links) Water quality regulators, such as the Tennessee Department of Environment and Conservation, are challenged by data scarcity when identifying surface water quality impairment causes and pollutant sources. Surface water quality model users also seek to identify pollutant sources and design and place best management practices to efficiently improve water quality, but have insufficient data for model calibration. This research documents the design and evaluation of a novel, intensive water quality data collection system consisting of a automatic sampler, bi-weekly grab sampling, and a long term deployment sonde. System design characteristics that were emphasized included a focus on gathering data for common impairment causes (pathogens, siltation, nutrients, and dissolved oxygen-DO) and water quality criteria not currently being evaluated (pH and temperature rate of change and diurnal DO fluctuations). In addition, the system was designed to gather data for watershed model calibration in rural, un-gauged watersheds because agriculture is listed as the predominant source of water quality impairment in Tennessee. Thus, the system was unmanned to reduce labor input, self-powered because of limited access to the electrical grid, provided sample preservation (refrigeration at low pH), and included stage measurement. Two identical prototype systems were installed in adjacent ecoregion 67g watersheds in Greene County, Tennessee: Lick Creek, impaired for pathogens, nutrients, and low DO, and Little Chucky Creek, which is unimpaired and a former ecoregion reference stream. The two primary objectives of this research were to evaluate the system power demand and determine whether a large water quality dataset improved impairment cause and source identification. A 270 watt solar panel power supply ultimately failed at Lick Creek during the summer when the refrigerated sampler cooling demand peaked, but was sufficient at Little Chucky Creek. System power supply design equations are provided, but with optimization the power supply used would likely be sufficient. The data collected did significantly improve insight into impairment cause identification. For example, total phosphorus rather than total nitrogen concentrations and low DO appeared to be a potential cause of impairment at Lick Creek. The system design was reliable and could be used to calibrate watershed models to improve source assessment. water quality TDEC stream assessment monitoring SWAT Agriculture Bioresource and Agricultural Engineering
2	Evaluating Substrate Metrics for Monitoring Sediment Impairment of East Tennessee Streams. Terrell, James Hunter 01 August 2011 (has links) Section 303(d) of the Clean Water Act (CWA) requires states to assess and list all streams that do not meet water quality criteria for their designated use classes. In Tennessee, the Tennessee Department of Environment and Conservation (TDEC) uses macroinvertebrate surveys to assess the condition of streams designated for “fish and aquatic life” and the progress of targeted waterbodies toward meeting established standards for sediment. As of yet, no substrate metric has been established to monitor water quality or to document progress toward water quality improvement with respect to fish and aquatic life in Tennessee. A substrate metric that could be efficiently measured and would represent the needs of aquatic species would be valuable for monitoring streams with known sediment impairment to detect water quality improvement. The objectives of this study were to (1) investigate the relationships between riffle substrates and benthic macroinvertebrate data, provided by TDEC; (2) assess the potential use of substrate metrics as a monitoring tool for benthic habitat status; and (3) examine variation in riffle substrates over time in the Ridge and Valley Ecoregion of Tennessee. Bed and interstitial sediment were characterized at sites corresponding with TDEC macroinvertebrate sampling stations. Bed sediment characteristics were significantly correlated with benthic macroinvertebrate data; however, interstitial fines yielded no significant correlations with benthic macroinvertebrate data. Substrate metrics did not differ significantly between varying levels of impairment; however, they did differ significantly when all impaired sites were combined into a single impairment group. The lack of significant differences between varying classes of reach impairment suggests that substrate metrics may not be able to distinguish impairment at the level necessary for monitoring impairment. However, substrate metrics may be of potential use in monitoring sites where impairment is less ambiguous. To investigate change in riffle substrate over time, three sites were monitored over the course of a year. Preliminary observations showed little change in riffle substrate during the study period, suggesting that seasonal restrictions on substrate surveys are unneccessary. embeddedness substrate aquatic habitat ecoregion 67 stream assessment fluvial geomorphology Environmental Monitoring Geomorphology Water Resource Management
3	Finding a Balance: The Intersection of Transportation Needs and Environmental Regulation and Protection Rahtz, Christine M. 01 December 2014 (has links) No description available. Environmental Science Water Resource Management environmental science Ohio Department of Transportation environmental consulting stream assessment wetland assessment environmental law permitting NEPA documentation
4	LAND COVER AND STREAM BIOLOGICAL INTEGRITY IN NORTH-CENTRAL INDIANA Alexandra Ann Adams (18066691) 28 February 2024 (has links) <p dir="ltr">The Temperate Plains ecoregion of Indiana has experienced significant agricultural development since the 19th century, which has left streams vulnerable to impacts such as sedimentation and nutrient accumulation. This thesis describes first the accuracy of the USDA Cropland Data Layer (CDL) in land cover change, and second, the relationships between agricultural and forested land covers and stream biological integrity. I first employed the CDL to review land cover change, particularly relating to agriculture and forest, for the area of interest between 2010 and 2020. I determined that the CDL improved in accuracy for the area of interest in the chosen timeframe for non-agricultural and non-forest land cover. I concluded that the CDL was best used as a supplement to primary-source land cover measures. Next, I calculated the fish Index of Biotic Integrity (IBI) scores for 20 sampled agricultural and forested streams in North-Central Indiana. I also assessed the stream habitats at all sites using the Qualitative Habitat Evaluation Index (QHEI) and percent cultivated crops in drainage basin areas for all streams. Forested streams had significantly higher QHEI scores than agricultural streams (median = 62 and 40.4, respectively). No other relationships were statistically different, including IBI and land cover category, which may have been due to the small sample size (n = 20). I concluded that future studies may build on these findings by controlling for agricultural drainage types or using precise measures of forested land cover.</p> Fisheries management Forestry management and environment Indiana Agriculture Stream Assessment land cover land use change Index of Biotic Integrity Cropland Data Layer
5	Testing and Refining a Unique Approach for Setting Environmental Flow and Water Level Targets for a Southern Ontario Subwatershed Beaton, Andrew 15 August 2012 (has links) In this study Bradford’s (2008) approach for setting ecological flow and water level targets is tested and refined through application within the Lake Simcoe Region Conservation Authority’s (LSRCA) subwatershed of Lover’s Creek. A method for defining subwatershed objectives and identifying habitat specialists through expert input is proposed and tested. The natural regime of each streamflow and wetland site is characterized along with the hydrological alteration at each site. Potential ecological responses to the hydrologic alterations are then hypothesized for the different types of changes calculated at each site. Methods for setting overall ecosystem health and specific ecological objective flow targets are proposed and tested. These targets are integrated into a flow regime for each site and a process for using this information for decision making is suggested. Flow magnitude quantification is attempted using hydraulic modelling and sediment transport equations, however the data used were found to be inadequate for this application. The accuracy of the targets developed using the method presented in this paper is mainly limited by the accuracy of the hydrological model and quantified flow magnitudes. Recommendations for improving these components of the assessment are made. The unique approach and recommendations presented in this paper provide explicit steps for developing flow targets for subwatersheds within the LSRCA. This research contributes toward the advancement of EFA within the LSRCA, which provides opportunity for enhanced protection and restoration of ecosystem health across the watershed. / Lake Simcoe Region Conservation Authority Ecological flows environmental flow instream flow in-stream flow indicators of hydrologic alteration ecological flow components Lovers Creek Lake Simcoe Watershed streamflow wetland hydroperiod MIKE-SHE HEC-RAS HEC-GeoRAS Du Boyes equation Ontario Stream Assessment Protocol OSAP IHA Southern Ontario Ontario LSRCA flow regime decision making Ontario hydrologic model hydraulic model brook trout amphibian swamp Ontario Wetland Evaluation System ecological function hydrological function expert interview Delphi Technique geomorphic framework river stream hydrology cold water fish Andrea Bradford aquatic aquatic habitat aquatic biology groundwater land use change urbanization pool riffle pool-riffle

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