<p> Global climate change may result in rising temperatures. As a result, ecological health and the human use of rivers may be impacted. The hydrologic cycle, watershed hydrology, and in-stream hydraulics are dynamic systems, influenced by human activities, natural events, and climate. Although known drivers like precipitation and stream velocity govern sediment processes, the effect of water temperature on sediment transport remains unclear. In-stream sediment movement could lead to blocked harbors, flooding, and degradation of vulnerable fish habitat. To better understand how fluctuations in water temperature affect sediment dynamics, six transport models were analyzed on the Niobrara River, with water temperatures ranging 1&deg; to 40&deg; C. The results indicate that as water warms sediment transport decreases, according to an inverse, non-linear law, with the highest reduction at colder water temperatures. The results given here can help predict changes in sediment transport for rivers with similar characteristics at various water temperatures. </p>

<p> Streamflow information is essential for many important uses across a broad range of scales, including global water balances, engineering design, flood forecasting, reservoir operations, navigation, water supply, recreation, and environmental management. </p><p> Natural streams are characterized by changes in cross-section geometry, slope, and geophysical properties (bed-roughness, channel slope, etc.) along their reaches. Variations in the shape and size of the channel bed geometry result from several interacting features of the river system including the effect of different flow regimes, slope, sediment load, etc. Simplifying the river bed geometries could reduce the burden of assembling the required data, so implementing less detailed routing procedures could lower the computational burden. &ldquo;At-a-station&rdquo; hydraulic geometry (AHG) relationships are power-law functions which relate river discharge to key the hydraulics (i.e., velocity, depth, width, and flow area). The AHG relations have been introduced and discussed among researchers, engineers, and geomorphologist since the '50s based upon a limited number of observations made over few flow monitoring stations across the United States. </p><p> This doctoral thesis starts with an introduction to statistical data filtering procedures that are being trained and tested over both synthetic and realistic data followed by being applied over ~4000 U.S. Geological Survey&rsquo;s river monitoring stations to compute AHG parameters based upon robust discharge-hydraulic measures. Given &ldquo;refined&rdquo; dataset, estimated AHG parameters are combined with morphological (channel pattern, channel slope, etc.) and geophysical features at a site. Doing so, potential interrelation among independent and dependent variables will be highlighted. Accordingly, given some assumptions, it is verified how well channel morphology and hydraulic components are intertwined and combined with AHG parameters and how categorizing river monitoring stations according to these characteristics will be practical and useful for further studies. For instance, the application of AHG parameters in modifying numerical hydraulic routing coefficients will result in an improvement in predictability of flood routing schemes (here, Muskingum-Cunge). The thesis will be concluded by the analysis of trade-off between computation time and accuracy or complexity vs. simplicity among advanced, hydrodynamic (HEC-RAS 2D) vs. low-complexity (AutoRoute and HAND) models that is also an alternative way to affirm the advantage of idealizing or simplifying a hydraulic system over-relying on time- and energy-costly approaches.</p><p>

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1928. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed September 16, 2009) Includes index (p. 67-69).

<p> The goal of this study was to identify practical, cost-effective drinking water source protection measures in the Comarca Ng&auml;be-Bugl&eacute;, a remote indigenous region of Panama. Water samples from 40 spring captures were tested for <i>E. coli</i> and total coliforms, and quality results were then compared with maintenance and source protection criteria using odds ratios. The water was contaminated; only two samples passed Panamanian drinking water standards--0 CFU/100 ml for <i>E. coli</i> and 3 CFU/100 ml for total coliforms. Mean <i>E. coli</i> was 187 CFU/100 ml and mean total coliforms was 2036 CFU/100 ml. Few odds ratio tests of source protection practices produced statistically significant results. However, the presence of animals within ten meters of the source and cleaning out the spring capture structure had statistically significant relationships with water quality at some contamination thresholds. Surprisingly, at one threshold, the presence of surface water near the spring was unrelated to water quality. Protecting water sources from livestock can be complicated in this region by ambiguous land tenure laws. Likewise, cleaning and basic maintenance are often done on a volunteer basis, and thus subject to the limitations of the community management model. Panamanian and foreign organizations seeking to improve drinking water source quality should consider these complex issues and offer financial and technical support as they encourage source protection improvements.</p>

<p> Water quality monitoring is essential to human health, ecological stability, and scientific research but remains hampered by Large, expensive, inflexible, and sometimes unreliable systems. To address these problems, an open source, flexible, and inexpensive sonde was designed and created capable of meeting research needs, along with a buoy system to support its use. A new optical UV based sensor was created to help measure phosphate ion levels. Together these technologies could further ecological research and help safeguard ecosystems.</p>

<p> The purpose of this study was to investigate the social, economic and technological factors that influence rates of adoption of innovative stormwater management approaches in municipal organizations in the Great Bay watershed, NH. The scope of this study was to investigate how innovations spread through municipal populations in a specific region and watershed area of the US. The methodology used mixed qualitative methods, including semi-structured interviews, case studies, and surveys to examine perceptions, attitudes, and beliefs that influence the adoption of innovative stormwater management solutions, as well as the governance characteristics of municipalities at different stages of adoption. Major findings include: adopter categories can be relatively easily and quickly categorized into early and late majorities as a preliminary means to identify populations of ready and willing audiences interested in and capable of advancing innovations; early and late adopter classifications followed general diffusion theory, but differed in substantial ways that could influence overall project or program success; and finally that early majority communities have more internal and external capacity to advance innovations as well as higher levels of peer-to-peer trust to offset perceptions related to economic risk that can either advance or stall innovative stormwater management solution adoption. This research offers insights on how to allocate scarce resources to optimally improve water quality through stormwater management solutions, and makes recommendations for how to effectively and efficiently generate greater understanding of complex barriers to adoption that thwart innovation in municipal governance organizations. One significant implication is that agents of change who want to move innovations through a broad municipal population should focus their efforts on working with innovators and early adopters that have status within relevant peer networks and who have capacity to evaluate the strengths and weaknesses of innovations.</p>

<p> The Cherokee Nation, a Federally-recognized Tribal government in Northeastern Oklahoma lacks Tribal water quality standards for numerical nutrient standards based on baseline conditions in the Cherokee Nation. Lotic waters are of special significance in Cherokee Nation culture and ceremonies. Three water quality standard priorities within the Tribe include defining Culturally Significant Waters as a designated use, identifying Culturally Significant Waterbodies and determining applicable numerical nutrient standards. Culturally Significant Water as a designated use was defined based on community surveys. Twelve rivers and streams were identified as a portion of the Culturally Significant Waters of the Cherokee Nation based on a tribal community survey using a Use Attainability Analysis. To address excess nutrients in the Cherokee Nation, a total phosphorus numerical nutrient criterion was determined using data for Culturally Significant Water bodies, literature guidance and the US Environmental Protection Agency recommended nutrient criteria process for the respective Aggregate Nutrient Ecoregion. The Oklahoma Scenic Rivers criterion of 0.037 mg/L total phosphorus for a 90-day geometric mean was evaluated and determined not to be protective of Cherokee Nation&rsquo;s Culturally Significant Waters. A total phosphorus criterion of 0.016 mg/L was recommended to protect Cherokee Nation Culturally Significant Waters from benthic algae greater than 100 mg/m² Chlorophyll <i>a.</i></p>

Thesis (M. Phil.)--University of Hong Kong, 1982.

<p> California Department of Water Resources (DWR) Snow Surveys Section has recently explored the potential use of recently developed hydrologic models to estimate snow water equivalent (SWE) for the Sierra Nevada mountain range. DWR Snow Surveys Section&rsquo;s initial step is to determine how well these hydrologic models compare to the trusted regression equations, currently used by DWR Snow Surveys Section. A comparison scheme was ultimately developed between estimation measures for SWE by interpreting model results for the Feather River Basin from: a) National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL) gridded SWE reconstruction product, b) United States Geological Survey (USGS) Precipitation-Runoff Modeling System (PRMS), and c) DWR Snow Surveys Section regression equations. Daily SWE estimates were extracted from gridded results by computing an average SWE based on 1,000 ft elevation band increments from 3,000 to 10,000 ft (i.e. an elevation band would be from 3,000 to 4,000 ft). The dates used for processing average SWE estimates were cloud-free satellite image dates during snow ablation months, March to August, for years 2000&ndash;2012. The average SWE for each elevation band was linearly interpolated for each snow sensor elevation. The model SWE estimates were then compared to the snow sensor readings used to produce the snow index in DWR&rsquo;s regression equations. In addition to comparing JPL&rsquo;s SWE estimate to snow sensor readings, PRMS SWE variable for select hydrologic response units (HRU) were also compared to snow sensor readings. Research concluded with the application of statistical methods to determine the reliability in the JPL products and PRMS simulated SWE variable, with results varying depending on time duration being analyzed and elevation range.</p>

<p> Nitrogen and phosphorus pollution in hydrologic ecosystems is a costly environmental problem. Low Impact Development measures, such as bioretention, can help prevent nutrient pollution. Bioretention is a type of green stormwater infrastructure and landscaping feature that collects, stores and treats stormwater runoff. Bioretention media is composed of sand, soil and an organic material such as compost or wood fines. While bioretention in itself is a sustainable practice, there is an ever growing demand for more sustainable solutions to the world's environmental problems. The St. Louis Metropolitan Sewer District's Lemay Waste Water Treatment (WWTP) incinerates biosolids, which creates a non-hazardous byproduct referred to as bottom ash. Incinerator bottom ash from the Lemay WWTP is mostly composed of silica and is very similar to sand. So, if incinerator bottom ash from the Lemay WWTP can be used in bioretention media as a substitute for sand, it will make a sustainable stormwater management technique even more sustainable. However, bioretention media with incinerator bottom ash will have to behave as a typical media to be an acceptable substitution. Nitrogen and phosphorus concentrations in the effluent from bioretention cells are of particular interest due to the drastic environmental issues associated with nutrient pollution. Therefore, a bioretention column study was performed to observe nutrient pollutant removal efficiency and plant compatibility of bioretention media containing municipal waste incinerator bottom ash. The results of the column study indicate that municipal waste incinerator bottom ash from the Lemay WWTP could be an acceptable substitution for sand in bioretention media.</p>