Thesis (Ph. D.) -- University of Maryland, College Park, 2007. / Thesis research directed by: Civil Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

Thesis (PhD) -- Auckland University of Technology, 2004. / Also held in print (142 leaves, col. ill., 30 cm.) in Wellesley Theses Collection. (T 628.21 NG)

Thesis (Ph. D.)--University of Alabama at Birmingham, 2009. / Additional advisors: Robert Angus, Paul D. Blanchard, Sarah Culver, Alan Shih. Description based on contents viewed June 3, 2009; title from PDF t.p. Includes bibliographical references (p. 48-51).

Drainage systems for the desert Southwest are currently designed without much consideration for the climatological or surficial conditions of the region. The "100 year" flood has become the design standard throughout the United States due to misunderstandings about requirements of the National Flood Insurance Program. The effect of larger floods is virtually ignored, seasonal variations of rainfall patterns and intensities are neglected, and hydrologic data collection is extremely limited in watersheds of the urbanizing Southwest. The laws of nature are obscured by the rules of man during the planning and design of desert drainageways. Procedures for extrapolating runoff records and estimating the magnitude of the 100-year flood, including the LP III probability density function, the NOAA Atlas, and HEC-1, have been widely adopted in the arid regions as part of local drainage regulations. Plans are normally not approved unless the basis of design complies with the regulations. Assumptions inherent in the methods are questionable and data to verify the assumptions are limited. Drainage design can be improved by using available field data and a simple method--based on the Rational Method--is developed. Benefit-cost analysis is a valuable tool for establishing project alternatives, project size, and cost/benefit allocation. An equitability index is defined for evaluating fairness, and it is combined with the benefit-cost ratio for refining and selecting project design. Estimates of flood peaks can be improved by considering channel abstractions as "negative base flow"; by recognizing the presence of the n-value paradox; by extending flood records through paleohydrologic study; by monitoring rainfall, runoff, and the effectiveness of design strategies in urban catchments; and by using more suitable rainfall estimates. Drainage design can be made more rational by also considering sediment transport; by including nonstructural design alternatives; and by evaluating a range of flood magnitudes, not just the 100-year flood. A conceptual drainage ordinance not based on the NFIP is presented.

This thesis develops and presents a practical, rapid and cost effective method of assessing the most efficient strategy to limit sediment and associated contaminants from entering and impacting on Auckland's waterways. Although sediment removal objectives have been defined by Auckland Regional Council's stormwater quality guidelines, the deployment of treatment systems based upon current best management practice does not ensure that these objectives will be achieved. Due to the lack of established methods for the collection and analysis of stormwater related contaminants, an elaborate sampling and analytical protocol was established to validate the results obtained. The research has been undertaken as a series of studies with specific sampling methodology described in detail at the beginning of each study. Current issues and practices relating to the local stormwater industry are also reviewed.The accumulation of metal contaminants in estuarine studies is typically considered in terms of the preferential accumulation of heavy metals in the sediment fine fraction and the accumulation of these contaminants in the bulk sediment. For these data to be considered in the context of stormwater treatment, a third factor, looking at the total mass load distribution of these contaminants within the particle ranges of sediment is introduced. This thesis proposes that a substantial amount of coarser particles are making their way into our receiving environment and that attached to them are a significant proportion of the total contaminant load. Although the contaminants on coarse particles may not be bioavailable in their original state, they undergo physical changes while in transport and once deposited the chemical and biological effects on the receiving environment will ultimately be just as detrimental.A contaminant yield assessment method is developed in which the removal efficiency of every stormwater contaminant can be accessed based on a target sediment removal range. From a cost-benefit perspective, the marginal benefit of higher contaminant removal is also discussed. Finally the framework of a contaminant-based stormwater model, incorporating provenance, nature and transport is developed to access the true nature of stormwater contamination discharged to the receiving environment. The model will generate generic particle and contaminant distributions, which may be used by policy makers to predict treatment efficiencies based on target sediment removal objectives.

This thesis describes two studies of the chemistry of freshwater streams in the Sydney basin. The first was a survey of 86 waterways, sampled under low conditions. Samples were generally low in salinity, soft, of poor buffering capacity and dominated by sodium and chloride. C0-dominance by calcium, magnesium and (bi)carbonate occured in a number of particular cases. Multivariate analyses indicated three groups, separated primarily by levels of dissolved nutrients, trace metals, turbidity and colour. Groupings were associated strongly with the type of catchment. Streams in areas relatively unaffected by human influence had notable uniformity in chemistry, while those from developed catchments were varied. Heavy metal contamination was relatavely low, although a few of the samples displayed inordinately large levels of one or more metals. In such cases the more extreme measurements of phosphorus and nitrogen were also seen. The findings were consistant with occasional or localised elevation of contaminant levels. The second study invloved monitoring of three Hawkesbury Sandstone streams. Sampling of surface waters, interstial waters and sediments was performing at irregular intervals over a two year period at three stations within each site. The streams predominantly existed under low conditions and showed similar major ion chemistries to the majority of the survey samples. Levels of calcium and total carbonate, plus heavy metals and nutrients were generally higher in the urbanised creeks, comapred to the reference strema. During a heavy storm, high levels of nutrients, suspended solids and colour were detected in all surface waters at peak-flow, as well as alkaline pH, oxidising redox, and reduced conductivity, alkalinity and hardness. The sandy sediments were characterised by very low levels of organic matter and cation exchange capacity. Sequential extractions identified that the sums of secondary phase lead, zinc and copper were over nine, four and two times that of the corresponding residual, respectively. Greatest proportions of zinc and lead were associated with coatings of iron and maganese oxides, or coarse waste particles. Copper was preferentially associated with organic matter. Concentration gradients between interstitial and surface waters were rare and release of sedimentary constituents should occur from the upper-most particulates. Poor water and sediment qualities were often observed in the urban sites. Poor water quality was also seen on occassion in the reference stream. However, since poor sediment quality was not detected at those times and interstitial waters for all sites displayed high within-site variability, surface waters were considered the most reliable short-term indicator of condition for Hawkesbury Sandstone streams. Multidimensional scaling showed that all streams had distinct water and sediment chemistries. High levels of temporal and spatial variability were apparant within the urbanised sites - particularly in interstitial waters - mostly due to concentrations of heavy metals, phosphorus and suspended solids. Seasonal differences were detected, but only in terms of the level of variability between summer and winter samples.

Thesis (M. L. A.)--University of Hong Kong, 2007. / Includes special report study entitled: Water level control technology in constructed wetland. Title proper from title frame. Also available in printed format.

Thesis (M.S.) -- University of Tennessee, Knoxville, 2006. / Title from title page screen (viewed on Feb. 7, 2007). Thesis advisor: Ernest Bazen. Vita. Includes bibliographical references.

Thesis (M.S.) in Natural Resources, Aquatic Toxicology--University of Wisconsin--Stevens Point, 2003. / Includes bibliographical references (leaves 75-82).

Thesis (M.S.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Sept., 24, 2003). Thesis advisor: Randall W. Gentry. Document formatted into pages (viii, 164 p. : ill. (some col., col. maps)). Vita. Includes bibliographical references (p. 117-122).