Water Resource Management Commons^™

Nitrate Runoff Contributing From The Agriculturally Intensive San Joaquin River Watershed To Bay-Delta In California, Ruoyu Wang

Ruoyu Wang

Dis And Distributed Watershed Models I, Jurgen Garbrecht, Fred L. Ogden, Paul A. Debarry, David R. Maidment

Fred L. Ogden

The increasing proliferation of spatial data, geographic information systems (GIS), and models for hydrologic applications provide many new investigation opportunities but also present a number of challenges for the uninitiated water resources practitioner. This two-part paper is intended for the practicing engineer who wants to expand into the arena of spatial data and distributed watershed modeling. It provides an integrated overview of the multiple facets of data-GIS-modeling issues and a source of background information for selection and application of GIS in watershed modeling. This first paper addresses selected spatial data issues, data structures and projections, data sources, and information on …

Dynamics Of Breakpoint Chlorination, Irvine Wei, J. Carrell Morris

Irvine W. Wei

No abstract provided.

Advanced Chemical Oxidation And Toxicity Reduction Of 2,4,6-Trichlorophenol By Using Fenton's Reagent: Part Ii, Dechlorination Kinetics, Somnath Basu, Venkat Sreenivasan, Irvine W. Wei

Irvine W. Wei

Laboratory investigation has shown that Fenton's Reagent is a very effective oxidant for 2,4,6-Trichlorophenol (TCP). The authors reported the first phase of this research, consisting of five different reactions of Fenton's Reagent on TCP, at the 1995 AIChE Summer National Meeting in Boston as Part I of this paper. The results demonstrated total removal of TCP, with almost complete release of aromatic ring bound chlorine atoms into chloride ions, significant reduction of TOC, and very importantly, significant toxicity reduction compared to the original substrate. These results suggested that Fenton's Reaction can be considered as a candidate process for treatment of …

Advanced Chemical Oxidation And Toxicity Reduction Of 2,4,6-Trichlorophenol By Using Fenton's Reagent: Part Iv, Reaction Mechanism And Kinetics, Somnath Basu, Irvine W. Wei

Irvine W. Wei

No abstract provided.

Evaluation Of Chlorine Emission Potential At The New Deer Island Wastewater Treatment Plant, Somnath Basu, Kenneth Shilinsky, Irvine Wei

Irvine W. Wei

The Massachusetts Water Resources Authority (MWRA) is currently constructing a 1,200 million gallon per day secondary wastewater treatment facility on Deer Island, in Boston Harbor. Chlorine, in the form of sodium hypochlorite solution, is purchased and barged to Deer Island for use in both effluent disinfection and odor scrubbing. The Process Engineering Department of Deer Island, as part of its on-going cost effectiveness program, is currently evaluating on-site generation of sodium hypochlorite. The technical analysis includes a thorough examination of the chemistry of production and storage, including potential losses to atmosphere. This paper presents an overview of that examination, defines …

Uv Disinfection Of Treated Wastewater Effluent: Influence Of Color, Reactivation And Regrowth Of Coliform Bacteria, Somnath Basu, Jack Page, Irvine Wei

Irvine W. Wei

Disinfection is a very important unit process to deactivate coliform bacteria in treated wastewater. However, regrowth potential of coliform bacteria raises human health and safety concerns associated with reuse of treated wastewater in various applications. Both post chlorination and post UV disinfection regrowth have been reported in the literature. In view of increasing use of recycled wastewater for reuse, it is necessary to address this phenomenon from both technical and regulatory standpoints. A case study of fecal coliform regrowth in a full scale operating plant is reported here. This is expected to aid in further understanding of the phenomenon and …

A Conceptual Continuous Process For The Treatment And Toxicity Reduction Of Wastewater Contaminated With 2,4,6-Trichlorophenol: Extended Abstract, Somnath Basu, Irvine W. Wei

Irvine W. Wei

Fenton's Reagent is an aqueous solution of ferrous ions and hydrogen peroxide. Through laboratory experiments Fenton's Reagent has been shown to be an excellent treatment agent for the removal of organic contaminants dissolved in water. It carries out oxidative degradation of various organic substrates using the principle of advanced chemical oxidation. This is an excellent alternate route for the removal of hazardous and toxic chemicals, which are recalcitrant to biological treatment. The authors of this paper conducted an extensive laboratory investigation to study the degradation of 2,4,6- Trichlorophenol (TCP) using Fenton's Reagent, reported elsewhere. The results indicated an optimum H₂O₂:TCP …

Computer Simulation Of Lime-Soda Water Softening Process, J. C. Y. Chen, I. W. Wei

Irvine W. Wei

No abstract provided.

Upflow Anaerobic Filter With Dual Media: A Novel Concept, K. Jain, I. Wei, A. Panchal, N. Varandani

Irvine W. Wei

To overcome two of the main problems intrinsic to upflow anaerobic filters using single media--clogging and biomass washout--a new strategy consisting of two different media is studied. The study is to evaluate the performance of Dual Media Upflow Anaerobic Filter (DM UAF), a novel wastewater treatment unit using synthetic waste as well as primary treated effluent of Common Effluent Treatment Plant (CETP), Vatva, India, operated by The Green Environment Services Co-Operative Society Ltd. and also to compare the performance of DM UAF with Single media UAF on a laboratory scale. Biokinetics of DM UAF was also determined. A 14.45 L …

Advanced Chemical Oxidation And Toxicity Reduction Of 2,4,6-Trichlorophenol By Using Fenton's Reagent: Part I, Kuang-Wei (Stone) Chen, Somnath Basu, Irvine W. Wei

Irvine W. Wei

The objective of this study is to exmnine the removal of a priority chlorinated aromatic pollutant, 2,4,6-Trichlorophenol (TCP), in aqueous solution by using Fenton's Reagent (a mixture of hydrogen peroxide and ferrous iron catalyst). Chlorinated phenols are priority pollutants, regulated by stringent discharge litnits. The presence of chlorine increases the toxicity of these phenolic compounds and decreases their biodegradability. Therefore, the processes of oxidation and dechlorination of chlorinated phenols by using Fenton's Reagent were employed in this study. Experiments were conducted in one-liter stirred batch reactors at 20°C. Three parallel reactors were used for reactions between 0.25 mM 2,4,6-TCP and …

An Assessment Of The Water Distribution System In The City Of Medford, Massachusetts, Yogesh Jitoo, Irvine Wei, Thomas R. Morgan, Donald Ouellette

Irvine W. Wei

The objective of this paper is to present the analysis of the water distribution system for the City of Medford, Massachusetts to identify areas of pressure deficiency. H₂OMAP Water Suite, modeling software, was used to assess the system, and using the calibrated hydraulic model of the water distribution system, the current available fire flows were compared to the required fire flows as determined by the Insurance Services Office (ISO) in 2002. Further, the influence of improvements made by the City to the distribution system from 2002 through 2004 to meet the required fire flows was evaluated. The model was also …

Enhanced Adaptive Management: Integrating Decision Analysis, Scenario Analysis And Environmental Modeling For The Everglades, Matteo Convertino, Christy Foran, Jeffrey Keisler, Lynn Scarlett, Andrew Loschiavo, Greg Kiker, Igor Linkov

Jeffrey Keisler

Pilot Study Of Greater Boston Drinking Water Quality Changes - Impacts Of Ozonation And Distribution System, Irvine W. Wei, Xin (Cindy) Huang, Windsor Sung

Irvine W. Wei

The Massachusetts Water Resources Authority (MWRA) provides drinking water to 2.2 million people in Greater Boston. To ensure good water quality without filtration, the MWRA is about to replace chlorination with ozonation as the primary disinfection at the new Walnut Hill Water Treatment Plant, scheduled to be on-line in 2005. The objective of this study was to understand the influence of ozonation on monochloramine decay and pH change in the MWRA system. The influence of the distribution system, which consists of old cast-iron pipes, on the ozonated water was also investigated. A pilot plant, including a simulated distribution system with …

Cyclic Heating To Inhibit Bacterial Growth In Activated Carbon Point-Of-Use Treatment Devices, Irwin Silverstein, Irvine W. Wei

Irvine W. Wei

The effectiveness of using heat treatment on a cyclic basis as a means of inhibiting bacterial growth in activated carbon point-of-use treatment devices was examined. Heat treated and non-heat treated devices were compared in a controlled experiment with respect to parameters such as standard plate count, total organic carbon, total residual chlorine and head loss. The results of the study indicated that cyclic heat treatment can inhibit bacterial growth on the surface of granular activated carbon without compromising total organic carbon and total residual chlorine removal efficiencies or accelerating head loss. Microbiological testing verified that the control device had become …

Advanced Chemical Oxidation Of 2,4,6-Trichlorophenol By Using Fenton's Reagent - Dechlorination And Toxicity Reduction, Kuang-Wei (Stone) Chen, Irvine W. Wei

Irvine W. Wei

Chlorinated phenols are priority pollutants, regulated by stringent discharge limits. The presence of chlorine increases the toxicity of these phenolic compounds and decreases their biodegradability. This study is to examine the removal of a priority chlorinated aromatic pollutant, 2,4,6-trichlorophenol (TCP), in aqueous solution by using Fenton's Reagent (a mixture of hydrogen peroxide and fenous iron catalyst), in terms of dechlorination and toxicity reduction. Test results indicate that the higher the molar ratio of H₂O₂ to TCP, the faster the release of chloride from TCP. However, the chloride released in all runs eventually approach the same level of theoretical chloride concentration, …

Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli

Jonathan G. Cooper

Climate change, understood as a statistically significant variation in the mean state of the climate or its variability, is the greatest environmental challenge of this generation (Intergovernmental Panel on Climate Change, 2001). Marshfield is already being affected by changes in the climate that will have a profound effect on the town’s economy, public health, coastal resources, natural features, water systems, and public and private infrastructure. Adaptation strategies have been widely recognized as playing an important role in improving a community’s ability to respond to climate stressors by resisting damage and recovering quickly. Based on review of climate projections for the …

Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli

Sally Miller

Climate change, understood as a statistically significant variation in the mean state of the climate or its variability, is the greatest environmental challenge of this generation (Intergovernmental Panel on Climate Change, 2001). Marshfield is already being affected by changes in the climate that will have a profound effect on the town’s economy, public health, coastal resources, natural features, water systems, and public and private infrastructure. Adaptation strategies have been widely recognized as playing an important role in improving a community’s ability to respond to climate stressors by resisting damage and recovering quickly. Based on review of climate projections for the …

First-Order Catchment Mass Balance During The Wet Season In The Panama Canal Watershed, Fred Ogden

Fred L. Ogden

Tropical hydrology is poorly understood for a number of reasons. Intense biological activity in the tropics introduces complexities to the hydrologic process. Bioturbation, rapid rates of decay, and intensive insect activity all tend to promote rapid flow paths in the upper soil. Aggressive weathering leads to clays depleted of light cations and deep soil profiles. Processes in the seasonal tropics are further complicated by seasonal transitions, and very large changes in catchment storage between seasons. Beginning in 2005, we installed a suite of hydrologic sensors in a 16.7 ha first-order catchment in the Panama Canal Watershed to observe hydrologic variables …

Exploring The Effects Of Aperture Size, Aperture Variability And Matrix Properties On Biocolloid Retention In A Single, Saturated Fracture, Margaret Burke

Sarah E Dickson

No abstract provided.

New Nanosystem Mixed Reactor For Urban Wastewater Treatment, Masoud Rastegar, Kamran Rahmati Shadbad

Masoud Rastegar

No abstract provided.

Mechanical Properties Of High Blaine Portland Cement, Masoud Rastegar, Kamran Rahmati Shadbad, Ali Hadidi

Masoud Rastegar

No abstract provided.

Effect Of Spontaneous Gas Expansion And Mobilization On The Aqueous-Phase Concentrations Above A Dense Non-Aqueous Phase Liquid Pool., Kevin G. Mumford, James Smith, Sarah E. Dickson

Sarah E Dickson

This paper presents a framework to quantify the overall variability of the model estimations of Total Polychlorinated Biphenyls (Total PCBs) concentrations in the Niagara River on the basis of the uncertainty of few model parameters and the natural variability embedded in some of the model input variables. The results of the uncertainty analysis are used to understand the importance of stochastic model components and their effect on the overall reliability of the model output and to evaluate multiple sources of uncertainty that might need to be further studied. The uncertainty analysis is performed using a newly developed point estimate method, …

Degradation Of Organic Pollutants In Domestic Wastewaters By Concrete Plates Containing Of Photocatalyst Nanoparticles, Masoud Rastegar

Masoud Rastegar

No abstract provided.

A Method For Computing Infiltration And Redistribution In A Discretized Moisture Content Domain, Fred L. Ogden

Fred L. Ogden

A new one-dimensional infiltration and redistribution method is proposed as an alternative to the Richards equation (RE) for coupled surface and subsurface models. The proposed method discretizes soil water content into hypothetical hydraulically interacting bins. The entry and propagation of displacement fronts in each bin are simulated by means of explicit infiltration and drainage approximations based on capillary and gravitational driving forces. Wetting front advances within bins create water deficits that are satisfied by capillary-driven interbin flow. The method inherently provides numerical stability by precluding the need to directly estimate nonlinear gradients through numerical schemes. Comparisons of the performance of …

Runoff Production In The Upper Rio Chagres Watershed, Panama, Fred Ogden

Fred L. Ogden

Runoff production in tropical watersheds is governed by a wide variety of potential sources and there have been few rigorous studies to date. The 414 km2 upper Río Chagres basin offers a unique opportunity to better understand the runoff production mechanisms in tropical watersheds through data analysis and modeling with rainfall and runoff data. Flow data and tipping bucket rain gage data are available at both the basin outlet (Chico gage) and for an 80.6 km2 internal basin location (Piedras gage). Modeling is performed using the Sacramento Soil Moisture Accounting Model (SAC-SMA), calibrated using data from 2000 and verified using …

Numerical Investigation Of Saturated Source Area Behavior At The Small Catchment Scale, Fred L. Ogden

Fred L. Ogden

The objective of this research is to explore the relationship between small catchment properties and the temporal growth and decay of saturated source areas (SSA). A simple physics-based hydrologic model, which we call the Sandbox model, is developed for this purpose. A thorough sensitivity analysis is undertaken to evaluate model response to variations in model parameters. Sandbox model output is compared to that from the semi-distributed conceptual model, TOPMODEL, a model with a wide spread acceptance. Plotting the temporal evolution of the extent of saturated source area versus catchment average soil water content dur- ing a number of wetting and …

Green And Ampt Infiltration With Redistribution, Fred L. Ogden

Fred L. Ogden

Distributed, physically based watershed and irrigation advance models require robust infiltration estimation capabilities. The empirical Green and Ampt (GA) equation of infiltration is a popular method for estimating infiltration. The GA parameters have physical basis and considerable prior research has focused on relating these parameters to soil textural classification. However, the original GA method is limited in that it is applicable only for a single ponding period. An explicit Green and Ampt redistribution (GAR) technique is developed herein to estimate interstorm redistribution of soil water and allow multiple ponding simulations using the GA methodology. Soil water redistribution during interponding periods …

Strength Of Bentonite Water-Well Annulus Seals In Confined Aquifers, Fred Ogden

Fred L. Ogden

The advantages of bentonite clay for sealing applications are well known. Bentonites have extremely low permeability, do not affect formation water chemistry, and have the ability to swell and deform in response to subsurface changes. The major limitation on the applicability of bentonite for water well annulus sealing is strength. Strength tests conducted in a physical model of a water well identified the expected magnitude of shear strength for several commercially available bentonite well-sealing products. The dependence of bentonite strength in the annulus of a water well on both setting time and borehole geometry is discussed. Force balance calculations for …

Setting Time Effects On Bentonite Water-Well Annulus Seals, Fred L. Ogden

Fred L. Ogden

Shear strength tests are conducted in a model of a water well on four, commercially available, granular bentonite well sealing products. The time dependency of annulus seal shear strength and resistance to piping is examined. Dry bentonite samples are placed through water in the annular space between the casing and borehole and allowed to set for a specified time. Pressure is applied at a constant rate to one end of the clay seal until shear or piping failure occurs. Pressure and seal displacement data are recorded on a digital data acquisition system. Annulus seal strength and resistance to piping increase …