Plankton communities and summertime declines in algal abundance associated with low dissolved oxygen in the Tualatin River, Oregon
Kurt D. Carpenter, Stewart A. Rounds
2013, Scientific Investigations Report 2013-5037
Phytoplankton populations in the Tualatin River in northwestern Oregon are an important component of the dissolved oxygen (DO) budget of the river and are critical for maintaining DO levels in summer. During the low-flow summer period, sufficient nutrients and a long residence time typically combine with ample sunshine and warm...
Classifications for Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) site-specific projects: 2010
William R. Jones, Adrienne Garber
2013, Data Series 745
The Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) funds over 100 wetland restoration projects across Louisiana. Integral to the success of CWPPRA is its long-term monitoring program, which enables State and Federal agencies to determine the effectiveness of each restoration effort. One component of this monitoring program is the...
Floral ecology and insect visitation in riparian Tamarix sp. (saltcedar)
D.C. Andersen, S. M. Nelson
2013, Journal of Arid Environments (94) 1-5-112
Climate change projections for semiarid and arid North America include reductions in stream discharge that could adversely affect riparian plant species dependent on stream-derived ground water. In order to better understand this potential impact, we used a space-for-time substitution to test the hypotheses that increasing depth-to-groundwater (DGW) is inversely related...
Use of general purpose graphics processing units with MODFLOW
Joseph D. Hughes, Jeremy T. White
2013, Ground Water
To evaluate the use of general-purpose graphics processing units (GPGPUs) to improve the performance of MODFLOW, an unstructured preconditioned conjugate gradient (UPCG) solver has been developed. The UPCG solver uses a compressed sparse row storage scheme and includes Jacobi, zero fill-in incomplete, and modified-incomplete lower-upper (LU) factorization, and generalized least-squares...
MODFLOW–USG version 1: An unstructured grid version of MODFLOW for simulating groundwater flow and tightly coupled processes using a control volume finite-difference formulation
Sorab Panday, Christian D. Langevin, Richard G. Niswonger, Motomu Ibaraki, Joseph D. Hughes
2013, Techniques and Methods 6-A45
A new version of MODFLOW, called MODFLOW–USG (for UnStructured Grid), was developed to support a wide variety of structured and unstructured grid types, including nested grids and grids based on prismatic triangles, rectangles, hexagons, and other cell shapes. Flexibility in grid design can be used to focus resolution along rivers...
Groundwater conditions in Georgia, 2010–2011
Michael F. Peck, Debbie W. Gordon, Jaime A. Painter
2013, Scientific Investigations Report 2013-5084
The U.S. Geological Survey collects groundwater data and conducts studies to monitor hydrologic conditions, better define groundwater resources, and address problems related to water supply, water use, and water quality. In Georgia, water levels were monitored continuously at 186 wells during calendar year 2010 and at 181 wells during calendar...
Detecting drawdowns masked by environmental stresses with water-level models
C.A. Garcia, K. J. Halford, J.M. Fenelon
2013, Ground Water (51) 322-332
Detecting and quantifying small drawdown at observation wells distant from the pumping well greatly expands the characterized aquifer volume. However, this detection is often obscured by water level fluctuations such as barometric and tidal effects. A reliable analytical approach for distinguishing drawdown from nonpumping water-level fluctuations is presented and tested...
Hydrogeology and water quality of the Dublin and Midville aquifer systems at Waynesboro, Burke County, Georgia, 2011
Gerard Gonthier
2013, Scientific Investigations Report 2013-5026
The hydrogeology and water quality of the Dublin and Midville aquifer systems were characterized in the City of Waynesboro area in Burke County, Georgia, based on geophysical and drillers’ logs, flowmeter surveys, a 24-houraquifer test, and the collection and chemical analysis of water samples in a newly constructed well. At...
Restoring a stream, restoring a community-urban watershed restoration fosters community improvement
Catherine Cullinane Thomas, Elizabeth Myrick
2013, Report
The Anacostia Watershed lies within the Chesapeake By drainage basin, and is one of the most urban watersheds within the basin. According to the Fish and Wildlife Service, the watershed spans over 175 square miles between Maryland and the District of Columbia and is considered by many to be one of...
High-water marks from flooding in Lake Champlain from April through June 2011 and Tropical Storm Irene in August 2011 in Vermont
Laura Medalie, S.A. Olson
2013, Data Series 763
The U.S. Geological Survey, in cooperation with the Federal Emergency Management Agency, identified high-water marks after two floods in Vermont during 2011. Following a snowy winter, new monthly precipitation records were set in Burlington, Vermont, in April and May 2011, causing extensive flooding from April through June. The spring 2011...
Great Lakes rivermouths: a primer for managers
Victoria Pebbles, James Larson, Paul Seelbach
Victoria Pebbles, James Larson, Paul Seelbach, editor(s)
2013, Report
Between the North American Great Lakes and their tributaries are the places where the confluence of river and lake waters creates a distinct ecosystem: the rivermouth ecosystem. Human development has often centered around these rivermouths, in part, because they provide a rich array of ecosystem services. Not surprisingly, centuries of...
Martian fluvial conglomerates at Gale Crater
Rebecca M.E. Williams, J.P. Grotzinger, W. E. Dietrich, S. Gupta, D.Y. Sumner, R. C. Wiens, N. Mangold, M. C. Malin, K.S. Edgett, S. Maurice, O. Forni, O. Gasnault, A. Ollila, Horton E. Newsom, G. Dromart, M.C. Palucis, R.A. Yingst, Ryan B. Anderson, Kenneth E. Herkenhoff, S. Le Mouélic, W. Goetz, M.B. Madsen, A. Koefoed, J.K. Jensen, J.C. Bridges, S.P. Schwenzer, K.W. Lewis, K.M. Stack, D. Rubin, L.C. Kah, J.F. Bell III, J.D. Farmer, R. Sullivan, T. Van Beek, D.L. Blaney, O. Pariser, R.G. Deen
2013, Science (340) 1068-1072
Observations by the Mars Science Laboratory Mast Camera (Mastcam) in Gale crater reveal isolated outcrops of cemented pebbles (2 to 40 millimeters in diameter) and sand grains with textures typical of fluvial sedimentary conglomerates. Rounded pebbles in the conglomerates indicate substantial fluvial abrasion. ChemCam emission spectra at one outcrop show...
Assessing factors affecting the thermal properties of a passive thermal refuge using three-dimensional hydrodynamic flow and transport modeling
Jeremy D. Decker, Eric D. Swain, Bradley Stith, Catherine A. Langtimm
2013, Journal of Waterway, Port, Coastal, Ocean Engineering (139) 209-220
Everglades restoration activities may cause changes to temperature and salinity stratification at the Port of the Islands (POI) marina, which could affect its suitability as a cold weather refuge for manatees. To better understand how the Picayune Strand Restoration Project (PSRP) may alter this important resource in Collier County in...
Hydrogen isotope investigation of amphibole and glass in dacite magmas erupted in 1980-1986 and 2005 at Mount St. Helens, Washington
S.J. Underwood, T.C. Feeley, M.A. Clynne
2013, Journal of Petrology
In active, shallow, sub-volcanic magma conduits the extent of the dehydrogenation–oxidation reaction in amphibole phenocrysts is controlled by energetic processes that cause crystal lattice damage or conditions that increase hydrogen diffusivity in magmatic phases. Amphibole phenocrysts separated from dacitic volcanic rocks erupted from 1980 to 1986 and in 2005 at...
Investigations of groundwater system and simulation of regional groundwater flow for North Penn Area 7 Superfund site, Montgomery County, Pennsylvania
Lisa A. Senior, Daniel J. Goode
2013, Scientific Investigations Report 2013-5045
Groundwater in the vicinity of several industrial facilities in Upper Gwynedd Township and vicinity, Montgomery County, in southeast Pennsylvania has been shown to be contaminated with volatile organic compounds (VOCs), the most common of which is the solvent trichloroethylene (TCE). The 2-square-mile area was placed on the National Priorities List...
Mineral resource of the month: diatomite
Water Resources Division, U.S. Geological Survey
2013, Earth (58) 57-57
The article discusses the properties and applications of the mineral diatomite. According to the author, diatomite is a soft, friable and very fine-grained siliceous sedimentary rock made of the remains of fossilized diatoms. The author adds that its properties make diatomite very useful as a filtration medium and as a...
Estimated rates of groundwater recharge to the Chicot, Evangeline and Jasper aquifers by using environmental tracers in Montgomery and adjacent counties, Texas, 2008 and 2011
Timothy D. Oden, Margot Truini
2013, Scientific Investigations Report 2013-5024
Montgomery County is in the northern part of the Houston, Texas, metropolitan area, the fourth most populous metropolitan area in the United States. As populations have increased since the 1980s, groundwater has become an important resource for public-water supply and industry in the rapidly growing area of Montgomery County. Groundwater...
Assessing the potential of reservoir outflow management to reduce sedimentation using continuous turbidity monitoring and reservoir modelling
Casey J. Lee, Guy M. Foster
2013, Hydrological Processes (27) 1426-1439
In-stream sensors are increasingly deployed as part of ambient water quality-monitoring networks. Temporally dense data from these networks can be used to better understand the transport of constituents through streams, lakes or reservoirs. Data from existing, continuously recording in-stream flow and water quality monitoring stations were coupled with the two-dimensional...
Colloid transport in saturated porous media: Elimination of attachment efficiency in a new colloid transport model
Lee L. Landkamer, Ronald W. Harvey, Timothy D. Scheibe, Joseph N. Ryan
2013, Water Resources Research (49) 2952-2965
A colloid transport model is introduced that is conceptually simple yet captures the essential features of colloid transport and retention in saturated porous media when colloid retention is dominated by the secondary minimum because an electrostatic barrier inhibits substantial deposition in the primary minimum. This model is based on conventional...
Chromophoric dissolved organic matter export from U.S. rivers
Robert G. M. Spencer, George R. Aiken, Mark M. Dornblaser, Kenna D. Butler, R. Max Holmes, Greg Fiske, Paul J. Mann, Aron Stubbins
2013, Geophysical Research Letters (40) 1575-1579
Chromophoric dissolved organic matter (CDOM) fluxes and yields from 15 major U.S. rivers draining an assortment of terrestrial biomes are presented. A robust relationship between CDOM and dissolved organic carbon (DOC) loads is established (e.g., a350 versus DOC; r2 = 0.96, p < 0.001). Calculated CDOM yields are also correlated to watershed percent wetland...
Short-term variability of 7Be atmospheric deposition and watershed response in a Pacific coastal stream, Monterey Bay, California, USA
Christopher H. Conaway, Curt D. Storlazzi, Amy E. Draut, Peter W. Swarzenski
2013, Journal of Environmental Radioactivity (120) 94-103
Beryllium-7 is a powerful and commonly used tracer for environmental processes such as watershed sediment provenance, soil erosion, fluvial and nearshore sediment cycling, and atmospheric fallout. However, few studies have quantified temporal or spatial variability of 7Be accumulation from atmospheric fallout, and parameters that would better define the uses and...
Seasonal comparison of aquatic macroinvertebrate assemblages in a flooded coastal freshwater marsh
Sung-Ryong Kang, Sammy L. King
2013, Open Journal Of Ecology (3) 94-101
Marsh flooding and drying may be important factors affecting aquatic macroinvertebrate density and distribution in coastal freshwater marshes. Limited availability of water as a result of drying in emergent marsh may decrease density, taxonomic diversity, and taxa richness. The principal objectives of this study are to characterize the seasonal aquatic...
Total nutrient and sediment loads, trends, yields, and nontidal water-quality indicators for selected nontidal stations, Chesapeake Bay Watershed, 1985–2011
Michael J. Langland, Joel D. Blomquist, Douglas Moyer, Kenneth Hyer, Jeffrey G. Chanat
2013, Open-File Report 2013-1052
The U.S. Geological Survey, in cooperation with Chesapeake Bay Program (CBP) partners, routinely reports long-term concentration trends and monthly and annual constituent loads for stream water-quality monitoring stations across the Chesapeake Bay watershed. This report documents flow-adjusted trends in sediment and total nitrogen and phosphorus concentrations for 31 stations in...
Water temperature and baseflow discharge of streams throughout the range of Rio Grande cutthroat trout in Colorado and New Mexico—2010 and 2011
Matthew P. Zeigler, Andrew S. Todd, Colleen A. Caldwell
2013, Open-File Report 2013-1051
This study characterized the thermal regime in a number of Colorado and New Mexico streams that contain populations of Rio Grande cutthroat trout (Oncorhynchus clarkii virginalis) and had no previous record of continual temperature records. When compared to Colorado’s water temperature criteria (Cold Tier 1), a portion of these populations...
Simulation of groundwater flow, effects of artificial recharge, and storage volume changes in the Equus Beds aquifer near the city of Wichita, Kansas well field, 1935–2008
Brian P. Kelly, Linda L. Pickett, Cristi V. Hansen, Andrew C. Ziegler
2013, Scientific Investigations Report 2013-5042
The Equus Beds aquifer is a primary water-supply source for Wichita, Kansas and the surrounding area because of shallow depth to water, large saturated thickness, and generally good water quality. Substantial water-level declines in the Equus Beds aquifer have resulted from pumping groundwater for agricultural and municipal needs, as well...