Water Resource Management Commons^™

Modeling Spatial And Temporal Variation In Natural Background Specific Conductivity, John Olson, Susan M. Cormier

John Olson

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson

John Olson

Tiered Approaches In Analyzing Rice Field Pesticide Fate And Transport For Ecological Risk Assessment, Ruoyu Wang

Ruoyu Wang

No abstract provided.

Assessment Of Optional Sediment Transport Functions Via The Complex Watershed Simulation Model Swat, Ruoyu Wang

Ruoyu Wang

Combined And Synergistic Effects Of Climate Change And Urbanization On Water Quality In The Wolf Bay Watershed, Southern Alabama, Ruoyu Wang

Ruoyu Wang

Biophysical And Hydrological Effects Of Future Climate Change Including Trends In Co2, In The St. Joseph River Watershed, Eastern Corn Belt, Ruoyu Wang

Ruoyu Wang

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Role Of Multiple High-Capacity Irrigation Wells On A Surficial Sand And Gravel Aquifer, Logan Seipel, Eric Wade Peterson, David H. Malone, Jason F. Thomason

Eric Wade Peterson

Estimation Of The Effects Of Climate Variability On Crop Yield In The Midwest Usa, Ruoyu Wang

Ruoyu Wang

Water Quality Effects Of Cellulosic Biofuel Crops Grown On Marginal Land, Ruoyu Wang

Ruoyu Wang

Responses Of Hydrological Processes And Water Quality To Land Use/Cover (Lulc) And Climate Change In A Coastal Watershed, Ruoyu Wang

Ruoyu Wang

The Effects Of Surface Water Velocity On Hyporheic Interchange, Timothy Sickbert, Eric Wade Peterson

Eric Wade Peterson

When evaluating hyporheic exchange in a flowing stream, it is inappropriate to directly compare stream stage with subsurface hydraulic head (h) to determine direction and magnitude of the gradient between the stream and the subsurface. In the case of moving water, it is invalid to ignore velocity and to assume that stage equals the net downward pressure on the streambed. The Bernoulli equation describes the distribution of energy within flowing fluids and implies that net pressure decreases as a function of velocity, i.e., the Venturi Effect, which sufficiently reduces the pressure on the streambed to create the appearance of a …

Individual And Combined Effects Of Land Use/Cover And Climate Change On Wolf Bay Watershed Streamflow In Southern Alabama, Ruoyu Wang

Ruoyu Wang

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 …

Variation Of Hyporheic Temperature Profiles In A Low Gradient Third-Order Agricultural Stream – A Statistical Approach, Vanessa Beach, Eric Wade Peterson

Eric Wade Peterson

Sediment size governs advection, controlling the hydraulic conductivity of the stratum, and conduction, influencing the amount of surface area in contact between the sediment particles. To understand the role of sediment particle size on thermal profiles within the hyporheic zone, a statistical approach, involving general summary statistics and time series cross-correlation, was employed. Data were collected along two riffles: Site 1: gravel (d50 = 3.9 mm) and Site 2: sand (d50 = 0.94 mm).Temperature probe grids collected 15-minute temperature data at 30, 60, 90, and 140 cm below the streambed surface over a 6-month period. Surface water and air temperature …

Identifying The Retention Mechanisms Of (Bio)Colloids In Single, Saturated, Variable-Aperture Fractures, Sandrina Rodrigues

Sarah E Dickson

No abstract provided.

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.

The Influence Of Hydrodynamic Forces On The Transport And Retention Of Colloids In Single Saturated Dolomitic Limestone Fractures, Mike Schutten

Sarah E Dickson

No abstract provided.

The Effects Of Evapotranspiration Upon Recharge Using The Stable Isotopes Of Oxygen And Hydrogen In The Carbonate Aquifers Of The Cumberland Plateau In Southeast Kentucky, Lee J. Florea

Lee J Florea, PhD, P.G.

In this brief manuscript, we consider the variation of the stable isotopes of oxygen, δ18O, and hydrogen, δ2H, in samples collected during 2010 and 2011 from precipitation and shallow groundwater along the Cumberland Plateau of southeast Kentucky. These data from the 1,900-ha Redmond Creek karst aquifer lend insight into the source and timing of recharge to shallow groundwater in the epigenic karst of the U.S midcontinent. Specifically, we find that only 43% of precipitation remains as potential recharge after accounting for evapotranspiration, and 85% of this potential recharge occurs during only four two-week sampling periods. The isotopic composition of precipitation …

Determining Nutrient And Sediment Critical Source Areas With Swat: Effect Of Lumped Calibration, Ruoyu Wang

Ruoyu Wang

A Comparison Of Biocolloid And Colloid Transport In Single Saturated Rock Fractures, Junlei Qu

Sarah E Dickson

No abstract provided.

Removal Of Perchlorate (Clo4-) From Water Using Pulsed Arc Electrohydraulic Discharge (Paed), Sarah E. Dickson

Sarah E Dickson

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, …

New Observations Of Gas-Phase Expansion Above A Dense Non-Aqueous Phase Liquid Pool, Kevin G. Mumford, James E. Smith, Sarah E. Dickson

Sarah E Dickson

The partitioning of volatile dense nonaqueous phase liquid (DNAPL) compounds to a discontinuous gas phase results in the repeated expansion, fragmentation, and vertical mobilization of gas clusters. This process has the potential to significantly affect the dissolution of DNAPL source zones and the characterization of DNAPL-contaminated sites, but has not been included in common conceptual models. This study presents new observations of discontinuous gas-phase growth above a 1,1,1-trichloroethane pool in a two-dimensional flow cell packed with 1.1-mm diameter sand. In contrast to the behavior observed in coarse glass beads, these visualization results show that the gas phase evolves as a …

A Simple Chemical Free Arsenic Removal Method For Community Water Supply – A Case Study From West Bengal, India, Bhaskar Sen Gupta Dr, U Rott Dr, Amitava Bandopadhyay Dr, W Degroot Dr, N K. Nag Dr, Angel Carbonell-Barrachina Dr, Soumyadeep Mukhopadhyay Dr

Soumyadeep Mukhopadhyay Dr

This report describes a simple chemical free method that was successfully used by a team of European and Indian scientists (www.qub.ac.uk/tipot) to remove arsenic (As) from groundwater in a village in West Bengal, India. Six such plants are now in operation and are being used to supply water to the local population (www.insituarsenic.org). The study was conducted in Kasimpore, a village in North 24 Parganas District, approximately 25 km from Kolkata. In all cases, total As in treated water was less than the WHO guideline value of 10 mg/L. The plant produces no sludge and the operation cost is 1.0 …

Influence Of Aperture Field Heterogeneity And Anisotropy On Dispersion Regimes And Dispersivity In Single Fractures, Qinghuai Zheng, Sarah E. Dickson, Yiping Guo

Sarah E Dickson

A 33 factorial experimental design was implemented to numerically investigate the interactive effect of the mean (μ b ), standard deviation (σ b ), and anisotropic ratio (AR) (λ b x /λ b y ) of single-fracture apertures on dispersion regimes (specifically Taylor dispersion and geometric dispersion) and dispersivity. The Reynolds equation was solved to obtain the flow fields in each computer-generated fracture, and the random walk particle tracking method was used to simulate solute transport. The simulation results show that (1) for a fixed hydraulic gradient, the dominant dispersion regime is controlled by μ b , and to a …

Differential Transport And Dispersion Of Colloids Relative To Solutes In Single Fractures, Qinghuai Zheng, Sarah E. Dickson, Yiping Guo

Sarah E Dickson

This work employed numerical experiments simulating colloid and solute transport in single parallelplate fractures, using the random walk particle tracking method, to demonstrate that (1) there exists an aspect ratio of the colloid radius to half the fracture aperture, do, where the average velocities of colloids and solutes are similar. When d > do, the velocity distribution assumption is satisfied, and the fact that the ratio of the colloid transport velocity to the solute transport velocity, sp, decreases as d increases is well documented in the literature. However, when d < do, the velocity distribution assumption is violated, and sp increases as d increases and (2) the Taylor dispersion coefficient and its extension by James and Chrysikopoulos [S.C. James, C. V. Chrysikopoulos, J. Colloid Interface Sci. 263 (2003) 288] will overestimate the colloid dispersion coefficient significantly. Additionally, numerical experiments simulating colloid and solute transport in variable-aperture fractures demonstrated that sp and DL,coll /DL,solute decrease with increasing CoV, and the anisotropy ratio only plays a minor role compared to the CoV. These observations have important implications towards the interpretation of colloid transport in both porous and fractured media.