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The management of transboundary river basins across developing countries, such as the Lower Mekong River Basin (LMB), is frequently challenging given the development and conservation divergences of the basin countries. Driven by needs to sustain economic performance and reduce poverty, the LMB countries are embarking on significant land use changes in the form hydropower dams, to fulfill their energy requirements. This pathway could lead to irreversible changes to the ecosystem of the Mekong River, if not properly managed. This thesis aims to explore the potential effects of changes in land use —with a focus on current and projected hydropower operations— on the Lower Mekong River network streamflow and instream water quality. To achieve this aim, this thesis first examined the relationships between the basin land use/land cover attributes, and streamflow and instream water quality dynamics of the Mekong River, using total suspended solids and nitrate as proxies for water quality. Findings from this allowed framing challenges of integrated water management of transboundary river basins. These were used as criteria for selecting eWater’s Source modelling framework as a management tool that can support decision-making in the socio-ecological context of the LMB. Against a combination of predictive performance metrics and hydrologic signatures, the model’s application in the LMB was found to robustly simulate streamflow, TSS and nitrate time series. The model was then used for analysing four plausible future hydropower development scenarios, under extreme climate conditions and operational alternatives. This revealed that hydropower operations on either tributary or mainstream could result in annual and wet season flow reduction while increasing dry season flows compared to a baseline scenario. Conversely, hydropower operation on both tributary and mainstream could result in dry season flow reduction. Both instream TSS and nitrate loads were predicted to reduce under all three scenarios compared to the baseline. These effects were found to magnify under extreme climate conditions, but were less severe under improved operational alternatives. In the LMB where hydropower development is inevitable, findings from this thesis provide an enhanced understanding on the importance of operational alternatives as an effective transboundary cooperation and management pathway for balancing electricity generation and protection of riverine ecology, water and food security, and people livelihoods.

Although acid mine drainage (AMD) in the Appalachian Coal Basin has been studied for decades, the effects of climate change on these streams are not well documented. Climate change predictions for this area include increased storm frequency and intensity, which may alter AMD generation, iron hydroxide precipitation, and fate and transport of contaminants and sediments. These processes substantially affect nutrient availability and the biological communities inhabiting these streams. This study investigates the potential effects of climate change on a treated AMD stream, Hewett Fork, by quantifying changes in nutrient concentrations, sediment transport, and algal biofilm biomass during normal and storm conditions. Nitrate, sulfate, and total reactive phosphorous concentrations were measured during each sampling event. Sediment transport was measured by quantifying sediment deposition and total suspended solids (TSS). The biological response to these conditions was measured by comparing algal biofilm biomass, quantified as chlorophyll a concentration, on stream rocks. Coupled with long-term meteorological, discharge, and chemistry data, the results of this study were used to create two conceptual models of Hewett Fork’s behavior during normal and storm conditions, respectively. Antecedent precipitation index (API) was used as an indicator of runoff potential to analyze the effects of recurring storm events on stream behavior. As API increased during normal and storm events, TSS concentrations increased, while chlorophyll a, conductivity, and sulfate concentrations decreased. TSS, nitrate concentration, and sediment deposition were higher overall during storm events. Total reactive phosphorous concentration remained low at all sites during the sample period, indicating that Hewett Fork may be phosphorous-limited. The results of this study indicate land use, mining, and treatment systems may contribute to lasting negative impacts on the biological community of Hewett Fork, if storms become more frequent and intense. Additionally, the inverse relationship between chlorophyll a values and sediment transport suggests water velocity may also exert significant control on the system.

At present, it is evident that there is a shift from rural to an urban settlement which results in high demand for residential buildings and other urban infrastructure. Blue – Green Infrastructure (BGI) is a system of using blue (water) and green (nature) to address urban and environmental challenges. The purpose of this study is to evaluate the environmental, social, and economic benefits of blue-green infrastructure in an urbanized area in Pittsburgh, Pennsylvania, USA. The study involves the utilization of Geographic Information System (GIS) to determine water quality level resulting from nonpoint source pollution through acquiring elevation data; watershed; and processing the elevation data through performing appropriate watershed delineation for the study area. Different landscape models (i-Tree Design, i-Tree Landscape) were explored to determine the different benefits attached to BGI Infrastructure aside aesthetic and refuge benefits from the Landscape Performance Series database. The i-Tree Landscape gives one an idea of areas where particulate matter and atmospheric gases exist, and areas to prioritize planting of trees. A pilot scale-site was chosen from the discovered areas to prioritize plantation with the help of some selected criteria. Five design patterns (Green Parks, Riverfront, Activity Nodes, Green Parking, and Green Streets) were adopted an I-Tree Design model was used to get the pre and post environmental and economic benefits of trees on a 10-yr. expectation plan. The water quality model, I discovered areas that have high total suspended solids (TSS) level giving one an idea on the water quality of the area. The areas pointed out as areas to prioritize planting by the i- Tree Landscape model also has a high TSS level from the GIS delineation to further justify the outcomes of the two models used. sustainable design concepts were provided on how to practice/ incorporate blue-green infrastructure in areas that need interventions towards creating a balance between the built and natural environment.

Transport and concentration of Total Suspended Solids (TSS) in forested streams play an important role in ecosystem health, affecting the health of fish populations and playing a role in nutrient delivery to floodplains. Despite a long history of studying TSS yields, estimates of TSS yields remain uncertain. Multiple methods have been commonly used to estimate time-aggregated TSS yields from water samples. This study investigated the effects of contemporary timber harvest practices on TSS yields as well as the robustness of conclusions to different methods of TSS yield calculation. TSS yields were calculated using linear interpolation, flow-weighted averaging, and statistical regression. The study utilized a paired-watershed design, with 6 years of calibration data between the control watershed and 2 treatment watersheds. One watershed was clearcut across 50% of its area and allowed to recover for the remaining 12 years of the study period. The other treatment watershed had 50% of basal area removed across 50% of it's total area. After the thinning treatment, the watershed was allowed to recover for 9 years before being clearcut across 46% of the area which was originally thinned. The watershed was then allowed to recover for the remaining 3 years of the study. Harvest impacts on TSS yield varied between treatment watershed and season, with the most significant changes occurring during spring (March through June). Furthermore, the different methods of TSS yield estimation provided different conclusions about TSS yield trends as well as total yields, with statistical regression providing the most consistently defensible estimates.

Since the Dust Bowl, conservation agriculture has become a common practice globally. Because of the rising interest in the use of corn biomass as a feedstock for biofuel production, the effects of corn stover removal on soil erosion were explored. It was hypothesized that selective harvesting strategies would impact soil erosion differently across a variety of slopes. Soil erosion boxes were constructed, and a rainfall simulator with an intensity of 30 mm hr-1 for 46 min was used to create runoff from slopes of 1, 5, and 10% and three cover factor treatments (no removal and two simulated corn stover removal strategies). Due to research time constraints, simulated corn roots were constructed to emulate actual corn roots in all experiments. The corn stover harvest strategies change the distribution of cobs, husks, leaves, and stalks in field; these changes were represented as the cover factor treatments. Changing the type of plant material on the soil surface impacted the predicted soil erosion from the Revised Universal Soil Loss Equation (RUSLE). Based on the results from this study, the effect of corn stover cover percentages had a significant impact on the predicted and observed soil loss.

Total suspended solids (TSS) are all particles in water that will not pass through a glass fiber filter with a pore size less than 2 μm, including sediments, algae, nutrients, and metals. TSS is an important water quality parameter because of its adverse effects on aquatic species and wildlife. The EPA has proposed a regulation for turbidity, a related water quality parameter, which has been stayed pending further testing. TSS is regulated through the EPA via the NPDES in many states. Since there are no accepted field tests for TSS, projects with TSS regulations must send samples to a laboratory for analysis, which can delay projects for days. The goal of this research was to develop a rapid, cost-effective, and consistent method for direct measurement of TSS in the field. Theoretical analyses of three initial designs (centrifugation, rapid heating, and rapid filtration using vacuum assist) showed that in order to obtain sufficient suspended material to measure in the field, too much water would be needed for each sample to be feasible for centrifugation and rapid heating. A new prototype rapid filtration system design was developed for evaluation. Subsequent testing showed this system to be inaccurate. A second system was modified the method was modified to for rapid filtration with no vacuum. Testing of this system also showed results were not precise enough to be a feasible field test. It was concluded that none of the described methods were currently feasible, and that the laboratory test could also have inaccuracies in measuring water samples tested to meet regulation standards. Adviser: John Stansbury

Highway storm water runoff contributes to the degradation of surface water quality in the United States. The most important pollutant in highway runoff is the total suspended solids (TSS). The United States Environmental Protection Agency (U.S.EPA) requires the runoff to be treated before it is conveyed to surface water. The exfiltration trench is one of the best management practices (BMP's) utilized by the Ohio Department of Transportation (ODOT) to treat highway runoff in-situ and consists of three layers: pervious concrete, type 3 backfill material (aggregate) and type 2 backfill material (sand). In this study, the exfiltration trench located on SR7, OH, is evaluated based on the pollutants' removal efficiency, particularly, TSS. TSS was removed at an efficiency of 41% in the originally constructed trench while the reconstructed trench achieved 69% TSS removal. Other water quality parameters investigated in this study include particle size analysis, turbidity and pH which were performed on both influent (highway runoff) and effluent (treated influent) samples.

Vertical accretion, the aggregation of material on a wetland surface, depends on organic matter accumulation and mineral sedimentation. We measured suspended sediment concentrations by total suspended solids (TSS), sediment deposition and vertical accretion rates in four marsh zones in the central basin of Mugu Lagoon, a salt marsh dominated by Salicornia pacifica. Mean TSS was 21±1 mg l-1 (Mean±SE) between February and May 2012, which is within the middle of the range of other salt marshes. Mean sediment deposition ranged from 0.00 g m-2 day-1 to 1.29 g m-2 day-1, which is in the low end of the range of other salt marshes. No net vertical accretion was observed between August 2011 and May 2012. Our results indicate that for high and high-mid marsh zones, sedimentation was highest adjacent to the creek. Interestingly, organic matter concentration in TSS varied with tide height, but mineral content did not. While more data are needed to confirm whether these trends occur over longer time periods, our study is one of the first to characterize spatial and temporal variation in sediment dynamics for a salt marsh dominated by Salicornia species.

The following is a compilation of field data collected in 2011 and 2012 in Apalachicola, FL as part of a five year study assessing the ecological effects of sea level rise in the northern Gulf of Mexico. Many coastal communities, both natural and developed, will soon be working to mitigate the effects of sea level rise, if they are not already doing so. This thesis investigates the natural patterns of the Apalachicola estuarine system through the collection and analysis of in situ water, sediment, and biomass samples. Additionally, results of the field samples are presented and recommendations for additional sampling are given. The field methods and procedures developed in this study were designed to be repeated in other estuaries to build upon the work that has been conducted in Apalachicola. Water samples were tested for total suspended solids (TSS) and compared against hydrodynamic (tidal circulation and streamflow) and meteorological (wind and precipitation) characteristics. Streamflow was determined to influence a seasonal base level concentration of TSS. Wind strength and direction consistently influenced small TSS concentration fluctuations, an effect amplified by the shallow nature of the estuary. Tidal circulation appeared to have minor influences on TSS concentration fluctuations within the base level concentration range. Precipitation appeared to influence large TSS concentration fluctuations; however, due to limited data collection during storm events, more data is required to conclusively state this. Sediment cores throughout the lower Apalachicola River revealed that coarse particles settled out in upstream areas while fine particles tended to stay in suspension until low energy areas in the lower portions of the river or marsh system were reached. Finally, biomass samples were used to iv develop regression models utilizing remotely sensed data to predict biomass density in marsh areas with unprecedented accuracy. The documented patterns of this system are to be used as inputs and validation points to update an existing hydrodynamic model and to aid in the coupling and development of sediment transport and marsh equilibrium models. The field campaign developed and implemented here provides a foundation for this novel coupled modeling effort of estuarine systems. From the 2011 and 2012 sampling conducted, it is apparent that Apalachicola can be modeled as a closed system with river inflow and sediment influx as boundary conditions. Forcing local conditions should accurately represent the system. Ultimately, these models will be used to simulate future sea level rise scenarios and will provide useful decision making tools to coastal managers. Future work will include replicating water sampling in subsequent wet and dry seasons in Apalachicola, FL to confirm observed trends, in addition to implementing this sampling in Grand Bay, MS and Weeks Bay, AL. Additional biomass samples will be taken to validate the strong correlations found between remotely sensed data and in situ samples. In similar studies, it is recommended that water samples be taken to adequately represent influences from tidal cycles and riverine inflow. It is also recommended that spatially distributed biomass samples be taken to validate regression models.

Rainfall generated surface runoff water could contaminate groundwater through transportation of suspended solids and organic matter in to the aquifer. Surface runoff water composition mainly depends on soil amendment. Surface runoff mainly contains clay, minerals, organic and inorganic matter, total dissolved lead, zinc. ECF technology presents an alternative for the removal of total suspended solids, turbidity, and organic matter from generated surface runoff water. This research presents development of bench scale ECF unit for the treatment of synthetic surface water. Experiments were conducted in a 10 liter Plexiglas unit provided with two aluminum electrodes, one serving as cathode, and other as anode. Direct current was applied to the electrodes by an external power supply. Optimal operational parameters were varied depends up on strength of the surface water. For low strength synthetic surface water the optimal operational variables were determined as an applied current of I = 2 ampere and a treatment time of 30 minutes. The overall turbidity removal efficiency was found to be 80 % and % transmittance was found 94.1 % under such conditions. For medium strength synthetic water the optimal operational variables were determined as an applied current of I = 3 ampere and a treatment time of 30 minutes. The overall turbidity removal efficiency was found 70 % and % transmittance was found 93 % under such conditions. Further experimentation was carried out on the determination combined maximum organic matter and turbidity removal efficiencies. Effect of chemical coagulants lime, aluminum sulfate octa decahydrate and ferric sulfate in ECF treatment was investigated.

Wastewater treatment facilities around the world use significant amount of energy which contributes to large quantities of greenhouse gas (GHG) emissions. According to the U.S.EPA, nearly 3% of the USA's energy is used to treat wastewater. This consumption is increasing at faster rates with increase in population and regulations. Wastewater facilities use large number of pumps in their transfer stations, treatment plants, and effluent pump stations. All these pumps consume considerable amounts of energy. This study presents a preliminary energy inspection of two facilities from Louisiana. This audit provides an inventory of the energy consumed for various activities like pumping, treatment, and discharge. This analysis helps the operators to identify the potential power consuming areas and optimize by adopting several energy conservation measures (ECMs). This study also involves the quantification of GHG emissions based on the energy consumption. The benefits of the study include minimizing energy and GHG emission.

Thousands rely on the water of Canandaigua Lake for drinking water, fishing, boating and swimming each year. The Canandaigua Lake Watershed Council (CLWC) was formed with the goal of protecting the high quality of this water source. The CLWC has been monitoring the lake and its tributaries for thirteen years. The lake remains in good condition, but testing has revealed an overall increase in total phosphorus (TP) and total suspended solids (TSS). This study identifies potential TSS and TP sources in the Eelpot Creek subwatershed. This creek has some of the highest concentrations of these pollutants in the entire Canandaigua Lake watershed. The area was compared to the Grimes Creek subwatershed, an adjacent watershed with similar characteristics but some of the lowest pollutant concentrations in the watershed. It was posited that the paucity of riparian forested buffers contributes to higher TSS and TP concentrations in Eelpot. GIS, ground-truthing, and chemical and macroinvertebrate analyses were used to locate potential pollutant hotspots throughout the subwatershed. Results showed no significant difference in macroinvertebrate community composition, except EPT richness, between the two subwatersheds or among sites. The results did demonstrate slight impact at some Eelpot sites, and one Grimes sampling site. GIS and ground-truthing revealed several areas of concern that appear to support the macroinvertebrate results. Cultivation appears to be a probable factor contributing to pollution in Eelpot, as well as heavy stream bank erosion found along some branches. Preliminary stormwater results appear to also support these conclusions, however there were too few samples to statistically analyze the results. The results of this study support the belief that much of the TSS and TP in Eelpot Creek stems from unbuffered cultivated land and/or stream bank erosion. It is therefore recommended that forested buffers be strongly considered in protecting this valuable water source.

Sanitary sewer overflow (SSO) has characteristics of high flow rate, low and varying pollutant concentrations, and low frequency of events. Fixed media bioreactor (biofilter) is a proven technology used for wastewater treatment in unsewered rural areas. No previous research has been published on SSO treatment with fixed media bioreactors. This study expands the application of fixed media bioreactor technology by testing its feasibility in the treatment of SSO wastewater at high hydraulic loading rates. Five types of fixed media bioreactors – sand, textile peat, textile/sand, and peat/sand – were set up in the laboratory and used to treat SSO once a month. Wastewater from a simulated 25-year peak flow was loaded to the surface of bioreactors at 0.2 m/hr for 6 hr. Biochemical oxygen demand (BOD5), total suspended solids (TSS), ammonia nitrogen (NH4-N) and total phosphorus (TP) were measured as waster quality characteristics. Sand bioreactors showed the best system performance for treating SSO with effluent concentration of 14 mg BOD5/L, which met 7-day effluent limit for stream discharge from conventional treatment technologies in Ohio's antidegradation rule (3745-1-05). Linear regression and Bayesian models were applied for the factor analysis of organic matter removal. The results showed that the type of bioreactor media was the most significant factor. All bioreactors had the effluent concentrations of TSS < 18 mg/L, the discharge standard of the Ohio antidegradation rule. The bioreactors had the highest efficiency in the NH4-N and TP removal for a relatively short SSO event of 2 hr. The treatment capacity decreased with higher influent concentration during 4 hr and 6 hr loadings. The treatment efficiency was also evaluated in sand bioreactors with different resting period between two SSO events and different dosing strategies. The low frequency of SSO (1, 2, 3 and 6 months resting between events) did not show significant impact on the treatment performance. The performance declined with high levels of organic matter at extremely high hydraulic loading rates. Ponding on the top and slow drainage were noted as operational problems and were resolved by distributing the SSO in small frequent doses in pilot-scale experiments.

According to the 2000 National Water Quality Inventory Report to Congress, over forty percent of our nation's lakes and rivers still do not meet water quality standards. Urbanization is one of the main causes of poor water quality in America. Increased impervious surface area due to new buildings and roadways means more water discharging when it rains and thus, more pollutants entering the receiving water bodies. One of the main pollutants of concern in storm water discharge is Total Suspended Solids (TSS). Other pollutants such as metals and nutrients may bind to the TSS particles, so a measurement of TSS is a good indicator of other pollutants in the water. Small-footprint storm water best management practices (BMPs) are products installed underground to provide primary treatment of storm water before it enters the receiving water body. Treatment consists of some form of sedimentation vault and a means for containing floatables such as oil and trash. These BMPs come in three main configurations: vertically cylindrical vault, horizontal vault, or filter combination. It was found through analysis of field studies submitted by the BMP companies that one configuration does not provide better removal efficiencies over another one. Removal efficiency is more a function of size than of configuration. The TSS removal efficiencies ranged from 0.75% to 98% for all BMP products analyzed.