This dissertation focused on developing a numerical model of spatial and temporal changes in bed morphology of ridge and slough features in wetlands with respect to hydrology and sediment transport when a sudden change in hydrologic condition occurs. The specific objectives of this research were: (1) developing a two-dimensional hydrology model to simulate the spatial distribution of flow depth and velocity over time when a pulsed flow condition is applied, (2) developing a process-based numerical model of sediment transport coupled with flow depth and velocity in wetland ecosystems, and (3) use the developed model to explore how sediment transport may affect the changes in bed elevation of ridge and slough landscape patterns observed in wetlands when a conditional pulsed flow was applied. The results revealed the areas within deep sloughs where flow velocities and directions change continuously. This caused enhanced mixing areas within the deep slough. These mixing areas may have had the potential to affect processes such as sediment redistribution and nutrient transport. The simulation results of solute/sediment transport model also supported the existence of areas within the domain where the mixing processes happened. These areas may have caused that nutrients and suspended particles stay longer time rather than entraining toward downstream and exiting the system. The results of bed simulation have shown very small magnitude of change in bed elevation inside deep slough and no changes on the ridge portion of the study area, when a conditional pulsed flow is applied. These findings may suggest that implementing pulsed flow condition did not increase suspended sediment concentration, which results in insignificant changes in bed morphology of a ridge and slough landscape. Therefore sediment transport may not play an important role in wetland bed morphology and ridge and slough stability. Results from the model development and numerical simulations from this research will provide an improved understanding of how wetland features such as ridge may have formed and degraded by changes in water management that resulted from increasing human activity in wetlands such as The Florida Everglades, over the past decades.

Climate change could aggravate periodic and chronic shortfalls of water, particularly in arid and semi-arid areas of the world (IPCC, 2001). Climate change is likely to accelerate the global hydrological cycle, with increase in temperature, changes in precipitation patterns, and evapotranspiration affecting the water quantity and quality, water availability and demands. The various components of a surface water resources system affected by climate change may include the water availability, irrigation demands, water quality, hydropower generation, ground water recharge, soil moisture etc. It is prudent to examine the anticipated impacts of climate change on these different components individually or combinedly with a view to developing responses to minimize the climate change induced risk in water resources systems. Assessment of climate change impacts on water resources essentially involves downscaling the projections of climatic variables (e.g., temperature, humidity, mean sea level pressure etc.) to hydrologic variables (e.g., precipitation and streamflow), at regional scale. Statistical downscaling methods are generally used in the hydrological impact assessment studies for downscaling climate projections provided by the General Circulation Models (GCMs). GCMs are climate models designed to simulate time series of climate variables globally, accounting for the greenhouse gases in the atmosphere. The statistical techniques used to bridge the spatial and temporal resolution gaps between what GCMs are currently able to provide and what impact assessment studies require are called as statistical downscaling methods. Generally, these methods involve deriving empirical relationships that transform large-scale simulations of climate variables (referred as the predictors) provided by a GCM to regional scale hydrologic variables (referred as the predictands). This general methodology is characterized by various uncertainties such as GCM and scenario uncertainty, uncertainty due to initial conditions of the GCMs, uncertainty due to downscaling methods, uncertainty due to hydrological model used for impact assessment and uncertainty resulting from multiple stake holders in a water resources system. The research reported in this thesis contributes towards (i) development of methodologies for climate change impact assessment of various components of a water resources system, such as water quality, water availability, irrigation and reservoir operation, and (ii) quantification of GCM and scenario uncertainties in hydrologic impacts of climate change. Further, an integrated reservoir operation model is developed to derive optimal operating policies under the projected scenarios of water availability, irrigation water demands, and water quality due to climate change accounting for various sources of uncertainties. Hydropower generation is also one of the objectives in the reservoir operation. The possible climate change impact on river water quality is initially analyzed with respect to hypothetical scenarios of temperature and streamflow, which are affected by changes in precipitation and air temperature respectively. These possible hypothetical scenarios are constructed for the streamflow and river water temperature based on recent changes in the observed data. The water quality response is simulated, both for the present conditions and for conditions resulting from the hypothetical scenarios, using the water quality simulation model, QUAL2K. A Fuzzy Waste Load Allocation Model (FWLAM) is used as a river water quality management model to derive optimal treatment levels for the dischargers in response to the hypothetical scenarios of streamflow and water temperature. The scenarios considered for possible changes in air temperature (+1 oC and +2 oC) and streamflow (-0%, -10%, -20%) resulted in a substantial decrease in the Dissolved Oxygen (DO) levels, increase in Biochemical Oxygen Demand (BOD) and river water temperature for the case study of the Tunga-Bhadra River, India. The river water quality indicators are analyzed for the hypothetical scenarios when the BOD of the effluent discharges is at safe permissible level set by Pollution Control Boards (PCBs). A significant impairment in the water quality is observed for the case study, under the hypothetical scenarios considered. A multi-variable statistical downscaling model based on Canonical Correlation Analysis (CCA) is then developed to downscale future projections of hydro¬meteorological variables to be used in the impact assessment study of river water quality. The CCA downscaling model is used to relate the surface-based observations and atmospheric variables to obtain the simultaneous projection of hydrometeorological variables. Statistical relationships in terms of canonical regression equations are obtained for each of the hydro-meteorological predictands using the reanalysis data and surface observations. The reanalysis data provided by National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) are used for the purpose. The regression equations are applied to the simulated GCM output to model future projections of hydro-meteorological predictands. An advantage of the CCA methodology in the context of downscaling is that the relationships between climate variables and the surface hydrologic variables are simultaneously expressed, by retaining the explained variance between the two sets. The CCA method is used to model the monthly hydro-meteorological variables in the Tunga-Bhadra river basin for water quality impact assessment study. A modeling framework of risk assessment is developed to integrate the hydro¬meteorological projections downscaled from CCA model with a river water quality management model to quantify the future expected risk of low water quality under climate change. A Multiple Logistic Regression (MLR) is used to quantify the risk of Low Water Quality (LWQ) corresponding to a threshold DO level, by considering the streamflow and water temperature as explanatory variables. An Imprecise Fuzzy Waste Load Allocation Model (IFWLAM) is adopted to evaluate the future fractional removal policies for each of the dischargers by including the predicted future risk levels. The hydro-meteorological projections of streamflow, air temperature, relative humidity and wind speed are modeled using MIROC 3.2 GCM simulations with A1B scenario. The river water temperature is modeled by using an analytical temperature model that includes the downscaled hydro-meteorological variables. The river water temperature is projected to increase under climate change, for the scenario considered. The IFWLAM uses the downscaled projections of streamflow, simulated river water temperature and the predicted lower and upper future risk levels to determine the fraction removal policies for each of the dischargers. The results indicate that the optimal fractional removal levels required for the future scenarios will be higher compared to the present levels, even if the effluent loadings remain unchanged. Climate change is likely to impact the agricultural sector directly with changes in rainfall and evapotranspiration. The regional climate change impacts on irrigation water demands are studied by quantifying the crop water demands for the possible changes of rainfall and evapotranspiration. The future projections of various meteorological variables affecting the irrigation demand are downscaled using CCA downscaling model with MIROC 3.2 GCM output for the A1B scenario. The future evapotranspiration is obtained using the Penman-Monteith evapotranspiration model accounting for the projected changes in temperature, relative humidity, solar radiation and wind speed. The monthly irrigation water demands of paddy, sugarcane, permanent garden and semidry crops quantified at nine downscaling locations covering the entire command area of the Bhadra river basin, used as a case study, are projected to increase for the future scenarios of 2020-2044, 2045-2069 and 2070-2095 under the climate change scenario considered. The GCM and scenario uncertainty is modeled combinedly by deriving a multimodel weighted mean by assigning weights to each GCM and scenario. An entropy objective weighting scheme is proposed which exploits the information contained in various GCMs and scenarios in simulating the current and future climatology. Three GCMs, viz., CGCM2 (Meteorological Research Institute, Japan), MIROC3.2 medium resolution (Center for Climate System Research, Japan), and GISS model E20/Russell (NASA Goddard Institute for Space Studies, USA) with three scenarios A1B, A2 and B1 are used for obtaining the hydro-meteorological projections for the Bhadra river basin. Entropy weights are assigned to each GCM and scenario based on the performance of the GCM and scenario in reproducing the present climatology and deviation of each from the projected ensemble average. The proposed entropy weighting method is applied to projections of the hydro-meteorological variables obtained based on CCA downscaling method from outputs of the three GCMs and the three scenarios. The multimodel weighted mean projections are obtained for the future time slice of 2020-2060. Such weighted mean hydro-meteorological projections may be further used into the impact assessment model to address the climate model uncertainty in the water resources systems. An integrated reservoir operation model is developed considering the objectives of irrigation, hydropower and downstream water quality under uncertainty due to climate change, uncertainty introduced by fuzziness in the goals of stakeholders and uncertainty due to the random nature of streamflow. The climate model uncertainty originating from the mismatch between projections from various GCMs under different scenarios is considered as first level of uncertainty, which is modeled by using the weighted mean hydro-meteorological projections. The second level of uncertainty considered is due to the imprecision and conflicting goals of the reservoir users, which is modeled by using fuzzy set theory. A Water Quantity Control Model (WQCM) is developed with fuzzy goals of the reservoir users to obtain water allocations among the different users of the reservoir corresponding to the projected demands. The water allocation model is updated to account for the projected demands in terms of revised fuzzy membership functions under climate change to develop optimal policies of the reservoir for future scenarios. The third level of uncertainty arises from the inherent variability of the reservoir inflow leading to uncertainty due to randomness, which is modeled by considering the reservoir inflow as a stochastic variable. The optimal monthly operating polices are derived using Stochastic Dynamic Programming (SDP), separately for the current and for the future periods of 2020-2040 and 2040-2060 The performance measures for Bhadra reservoir in terms of reliability and deficit ratios for each reservoir user (irrigation, hydropower and downstream water quality) are estimated with optimal SDP policy derived for current and future periods. The reliability with respect to irrigation, downstream water quality and hydropower show a decrease for 2020-2040 and 2040-2060, while deficit ratio increases for these periods. The results reveal that climate change is likely to affect the reservoir performance significantly and changes in the reservoir operation for the future scenarios is unable to restore the past performance levels. Hence, development of adaptive responses to mitigate the effects of climate change is vital to improve the overall reservoir performance.

Stakeholders’ perceptions of social, environmental, and economic concerns in the Rookery Bay Estuary were examined through this research. The purpose of this study was to discover the shared value and common resolution responses for the people of the Rookery Bay area that can extend to other local environmental management scenarios. Using Stakeholder Theory, Rational Choice Theory, Symbolic Interactionism, and Systems Theory as theoretical foundation, the following research questions were considered: RQ1) What are the points of shared value of community stakeholders facing environmental management issues? RQ2) How do the perspectives of the community stakeholders toward the social, environmental, and economic issues relate to their local environmental decision-making? RQ3) What are the attitudes and behaviors toward water? Participants identified the importance of water and the natural environment on the community. Additionally, participants were aware of the social, economic, and environmental issues and noted tension between stakeholders; however, they have a limited understanding of the concept of shared value. This research illustrates the benefit of weaving concepts from various fields together to strengthen the conflict studies field.The findings and recommendations in this research offer an outline that provides a path from dispute to common value generation that leads through creating shared meanings, a shared understanding, a shared story, to shared value that is stable over time.

A governança da água apresenta-se como caminho e paradigma na implementação de uma gestão descentralizada e participativa capaz de permear, com estes princípios, todas as instâncias e instrumentos de gestão. A outorga de direito de uso da água é um dos instrumentos previstos nas legislações federal e estadual (SP) cuja utilização permite controlar o acesso quantitativo e qualitativo a estes recursos. Concedida em consonância com as normas, critérios e diretrizes previamente estabelecidas, é a outorga que concede o direito e autoriza o uso privativo de bem público de uso comum do povo por particular, isto é, o uso da água. É também por meio da outorga que são disciplinados os usos considerados prioritários, insignificantes e orientada a alocação da água nas Bacias Hidrográficas. Especificamente quanto às diretrizes que orientam sua alocação, destaca-se a função do Plano de Bacia. Elaborado no âmbito dos Comitês de Bacias Hidrográficas, cabe ao Plano de Bacia, também chamado de Plano de Recursos Hídricos, oferecer as bases para a alocação da água, por meio das outorgas de direito, determinando seu parâmetro e comportamento nos diferentes regimes hídricos, incluindo os de agravamento de escassez hídrica. Diante deste contexto, o presente trabalho aprofunda as discussões e busca avaliar as restrições impostas às outorgas na Bacia Hidrográfica dos rios Piracicaba, Capivari e Jundiaí (PCJ) entre 2014 e 2017, seus fundamentos e observância aos princípios da descentralização e da participação. A partir dos elementos que compõe o conceito de governança da água e da contextualização da água no ordenamento jurídico brasileiro, o trabalho analisa, com apoio nas normas vigentes, os elementos e características da outorga de direito de uso da água, bem como sua relação com o Plano e com o Comitê de Bacia. Em seguida, analisa-se o Plano vigente durante o período escolhido em três diferentes dimensões: quanto à composição do Comitê e das Câmaras Técnicas atuantes em sua elaboração, quanto ao processo de contratação, elaboração e aprovação e quanto ao seu conteúdo, especialmente na constatação de diretrizes aplicáveis às restrições incidentes sobre as outorgas em períodos de agravamento da escassez. São também analisadas as atuações da Agência Nacional de Águas (ANA) e do Departamento de Águas e Energia Elétrica do Estado de São Paulo (DAEE) e as restrições estabelecidas, por meio de atos normativos, e que incidiram sobre outorgas entre os anos de 2014 e 2017. Constata-se, ao fim, o pequeno envolvimento do Comitê na elaboração do Plano de Bacia vigente à época, a lacuna de seu conteúdo no tratamento de situações críticas e emergenciais e a centralização da concepção das medidas de restrição das outorgas de direitos de uso na bacia dos rios PCJ, restrições estas que se mostram incompatíveis com as diretrizes do quadro normativo vigente. / Water governance presents itself as a path and paradigm in the implementation of a decentralized and participative management that is capable to permeate, with these principles, all the instances and instruments. The water grant is one of the instruments provided by the federal and state (SP) laws, which allows to control quantitative and qualitatively the access to these resources. When granted in accordance to the regulatory standards, criteria and guidelines previously established, the water grant guarantees the right and authorizes the private use of a commonweal by particular, that is, the use of water. It is also through the water grant that uses are disciplined according to its priority, meaningless and the water allocation is oriented in the River Basins. Specifically regarding the guidelines that lead its allocation, the function of the Basin Plan is highlighted. Being repared in the scope of the River Basins Committees, it is the responsibility of the Basin Plan, also called as Water Resources Plan, to provide the basis for the water allocation, by the water grant, defining its parameters and behavior in the different water polities, including those of water shortage aggravation. In the view of this context, the current research deepens the discussions and seeks to evaluate the restrictions imposed to the water grant on Piracicaba, Capivari and Jundiaí (PCJ) the River Basin between 2014 and 2017, its foundations and compliance with the principles of decentralization and establishment. Based on the elements that make up the concept of water governance and the contextualization of water in the Brazilian legal system, the research analyzes, with the support of current regulatory standards, the elements and characteristics of water grant, as well as its relation with the Plan and Basin Committee. Afterwards, the current Plan is analyzed according to the selected period in three different dimensions: in regards of composition of the Committee and the Technical Chambers involved in its elaboration, contracting process, elaboration and approval and its content, especially in the verification of the applicable guidelines to restrictions on concessions of water grant in times of shortages aggravation. It is also analyzed the actions taken by the National Water Agency (ANA) and the Department of Water and Electric Energy of the State of São Paulo (DAEE) and the restrictions established, through normative acts, and that affects the water grants between 2014 and 2017. Finally, it is possible to verify the little involvement of the Committee in the Basin Plan elaboration in force at the time, lacks of its content in the treatment of critical and emergency situations, and the centralization in the conception of the restricting measures of the water grant in the PCJ river basins, restrictions that are shown incompatible with the guidelines of the current regulatory framework.

This project developed a model for effective asset management drawn from successful programs in the United States, Australia, and New Zealand. Asset management practices were examined at the City of Ontario Utilities Department; a medium sized utility, and also at the Rainbow Municipal Water District, a small sized utility. Gaps between the ideal model and the existing practices were investigated.

Conventional wastewater treatment in the U.S. is an energy dependent and carbon dioxide emitting process. Typical mechanical systems consume copious amounts of energy, which is most commonly produced from fossil fuel combustion that results in the production of CO2. The associated organic load is also metabolized by microorganisms into CO2 and H2O. As the desire to reduce CO2 output becomes more prominent, it is logical to assess the costs of conventional treatment methods and to compare them to alternative, more sustainable technology. Vegetated Sand Bed (VSB) and Reed Bed (RB) systems are green technologies that provide environmentally superior treatment to conventional systems at a fraction of the cost both environmentally and economically. Using mass balance equations the net CO2 produced from wastewater treatment at 3 conventional facilities, (Amherst, MA, Ithaca, NY and Shelburne-Buckland, MA) and 3 VSBs, (Lloyd, NY, Shushufindi Slaughterhouse, Ecuador and Shushufindi Municipal Facility, Ecuador), will be estimated. Carbon dioxide sources considered are BOD5 microbial respiration, power demand, and sludge treatment. Using the BOD5 reduction and the average daily flow from each of the conventional facilities, hypothetical VSB and RB systems will be sized for the 3 conventional systems. The land area for each hypothetical VSB and RB and the CO2 reduction for equal treatment are estimated for each conventional facility. Estimates of annual CO2 production for Amherst, Ithaca, and Shelburne-Buckland, are 3,021 metric tons, 5,575 metric tons, and 158 metric tons of, respectively. The annual CO2 reduction potential for the conventional facilities Amherst, Ithaca, and Shelburne-Buckland, when compared to VSB and RB technology is estimated to be 74.0%, 83.2%, and 86.3% respectively. VSB and RB technology also provide promising results for sustainable wastewater treatment and reuse. Ammonium and nitrate reduction at the Joseph Troll Turf Plot VSBs were 72% and 88% respectively. The mean ammonium microbial growth rate constant was – 0.14 d-1 and the mean nitrate microbial growth rate constant was – 0.23 d-1. The implications are ammonium and nitrate reduction is possible with VSB and RB technology. Further investigation to understand the processes and fate of nitrogen including separate testing of ammonium and nitrate reduction are recommended.

No description available.

Problémy s vodou, zejména její nedostatek a znečištění, ovlivňují každodenní lidský život a hospodářský vývoj. Globální změny klimatu zvyšují pravděpodobnost a četnost extrémních událostí jako jsou sucho a záplavy. Rostoucí problémy s nepravidelnou dostupností a znečištěním vody vyžadují pokročilejší metodiky hodnocení vodních zdrojů, které povedou k efektivnímu využití a hospodaření s vodou. Tato práce se zabývá rozšířenými metodikami pro hodnocení vody z pohledu její kvality a kvantity a pro hodnocení spotřeby energie a produkce emisí souvisejících s vodou. Tři hlavní metodiky jsou navrženy na základě konceptu vodní stopy (Water Footprint) a pinch analýzy vody (Water Pinch Analysis) pro posouzení kvantitativních a kvalitativních hledisek využití a spotřeby vody. Použití těchto metod je rovněž demonstrováno pomocí numerických a empirických případových studií zaměřených na hodnocení a optimalizaci využití regionálních a průmyslových vodních zdrojůDále jsou diskutovány souvislosti mezi vodou a energií (Water-Energy Nexus) za účelem analýzy problémů týkající se vody z širší perspektivy. Z pohledu vody a vodních zdrojů je provedeno počáteční zhodnocení energetické náročnosti a produkce emisí skleníkových plynů v problematice odsolování mořské vody. Výsledky prezentované v této práci navazují na současné metodiky hodnocení vodních zdrojů. Stopa dostupnosti vody (Water Availability Footprint) byla navržena pro zohlednění dopadu degradace kvality vody ve stávajících postupech pro posuzování nedostatku vody, ve kterých nebyla dříve řešena. Druhým přínosem této práce je návrh konceptu kvantitativní-kvalitativní vodní stopy (Quantitative-Qualitative Water Footprint - QQWFP), ve kterém je definována vodní stopa z pohledu nákladů a následně je stanovena v souvislosti s celkovými náklady na spotřebu vody a odstraňování kontaminantů, které se do vody dostávají v průběhu jejího využití. Vodní stopa založená na nákladech poskytuje výsledky, které jsou intuitivnější jak pro management vodních zdrojů tak i pro veřejnost. Tento přístup umožňuje lépe kontrolovat a řídit průmyslové a regionální využívání a správu vody. Třetím přínosem této práce je rozšíření pinch analýzy nedostatku vody (Water Scarcity Pinch Analysis - WSPA), ve které je aplikována pinch analýzy vody na makroúrovni se zaměřením na regionální hodnocení a optimalizaci zdrojů a využívání vody. Všechny tři navržené metody jsou zaměřeny na stanovení dopadů využití vody z hlediska jejího množství a kvality, analýzy QQWFP a WSPA také pokrývají dopady vícečetných kontaminantů. Kromě hledání řešení se tato práce také pokouší naznačit potenciální směry pro budoucí výzkum v dané oblasti. Mezi významná potenciální témata k diskuzi patří 1) pokročilejší metoda kvantifikace vlivu více kontaminantů a 2) implementace a analýza ekonomické proveditelnosti přístupů WSPA a QQWFP s lokalizovanými daty s cílem nalézt přizpůsobené řešení pro optimální využití regionální a průmyslové vody.

The paradigm shift in water quality management of South African water resources was based on current international trends. This significant move was from a previous emphasis on source management to a focus on finding a balance between water resource protection and water use. The current approach requires that water quality and quantity should be maintained for sustainable functioning of both the natural aquatic environment and socioeconomic development. This approach has placed the assessment of water quality status as a key decision tool in water quality management. Various assessment tools have been utilized to quantify the quality of South African water resources. In this study we assessed the compatibility of some of the methodologies that have been used in the Department of Water Affairs to determine and report on the water quality status of the resource. During the assessment the context and manner in which these methodologies can be utilized in water quality management were also addressed The Compliance Evaluation and Fitness for use categorization methodologies are both used to describe the water quality threshold of potential concern when dealing with the resource. Compliance Evaluation methodology uses a pass or fail assessment, while the Fitness for use categorization methodology uses a scaled approach allowing for the assessment of gradual change in the system. The out puts of these two methodologies, the Resource Water Quality Objectives and Fitness for use categories/ classes have both been used in the department as benchmarks to describe the current water quality status The assessment of the two methodologies indicated that there are similarities in the approaches and the principles behind the two processes. The observation of the results, however, indicated differences in the manner of presentation of the results, the interpretation of the outcome and in how water quality management measures that needs to be implemented are linked. Both methodologies are easy to apply when conducting water quality status assessments. However, the two methodologies are not sufficient on their own when making decisions on water quality management. It was concluded that although the compliance evaluation methodology can play a pivotal role when setting end of pipe standards, the process needs to consider the gradual changes of water quality in the river system in order to enable instigation of different water quality management measures at appropriate levels. Further it was recommended that with some modification the two approaches can be applied to assess water quality to support adequate water quality management decisions at various levels. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Animal and Wildlife Sciences / Unrestricted

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis Obispo (SLO) County and Morro Bay Watershed by analyzing data of application by mass, area, and intensity to identify herbicides with the highest potential for local environmental pollution. California Pesticide Use Annual Summary Reports (PUASR) from the years 2000 to 2017 were used to obtain data for conducting a meta-analysis to estimate total herbicide application by weight within every township, range, and section for each of the eight selected herbicides: oxyfluorfen, glyphosate, diuron, chlorthal-dimethyl, simazine, napropamide, trifluralin, and oryzalin. A second goal was to select an analytical laboratory that would be best suited for herbicide analysis of estuary sediments to determine the presence, or lack thereof, of the eight selected herbicides. Criteria of consideration in laboratory selection included herbicides detection capabilities, detection/reporting limits, testing prices, chain of custody protocols, turnaround times, and laboratory site locations. The meta-analysis yielded results showing high herbicide application rates in SLO County with glyphosate, oxyfluorfen, and chlorthal-dimethyl being identified as three herbicides of elevated risk for local environmental contamination due high rates of use by mass, by area, and/or intensity during the study timeframe. Additionally, Morro Bay Watershed exhibited moderate rates of herbicide application with chlorthal-dimethyl and glyphosate being of highest risk for contamination and accumulation within the estuary because of high application rates by mass, by area, and/or intensity. Finally, Environmental Micro Analysis (EMA) and Primus Group, Inc. (PrimusLabs) were identified as the top candidates for analytical laboratory testing of Morro Bay Estuary sediment samples to be obtained and tested for the selected herbicides. These laboratories provide superior analytical capabilities of the eight herbicides, impressive reporting limits or lower detection limits, competitive testing prices for detecting multiple constituents in multiple samples, robust chain of custody protocols, options for quick turnaround times, and laboratory site locations within California.