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At least 289 records · Page 16Linked to original sources
USGS2004

Pesticides detected in urban streams in King County, Washington, 1998-2003

The U.S. Geological Survey and the King County Department of Natural Resources collected water samples from 14 sites on urban streams in King County during storms and during base flow between 1998 and 2003. The samples were analyzed for the presence of 155 pesticides and pesticide transformation products. Thirty-nine of the compounds were detected at least once during the study: 20 herbicides, 9 insecticides, 2 fungicides, 6 pesticide transformation products, and 2 other types of compounds. The most widespread compound was 4-nitrophenol, which was detected at all 14 sampling sites. The most frequently detected compound was pentachlorophenol, a fungicide, which occurred in more than 80 percent of the samples. The most frequently detected herbicides were prometon, trichlopyr, 2,4-D, and MCPP, and the most frequently detected insecticides were diazinon and carbaryl. All of the most frequently detected herbicides and insecticides were sold for homeowner use over the timeframe of this study. More compounds were detected during storms than during base flow, and were detected more frequently and typically at high concentrations during storms. Seven compounds were detected only during storms. Most of the compounds that were detected during storms occurred more frequently during spring storms than during autumn storms.

Scientific Investigations Report↗
USGS2012

Biodegradation of chloroethene compounds in groundwater at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, 1999-2010

The U.S. Geological Survey evaluated the biodegradation of chloroethene compounds in groundwater beneath the former landfill at Operable Unit 1 (OU 1) of the U.S. Naval Undersea Warfare Center (NUWC), Division Keyport. The predominant contaminants in groundwater are the chloroethene compounds trichloroethene, cis -1,2-dichloroethene, and vinyl chloride. The remedy selected for groundwater contamination at OU 1 includes phytoremediation and natural attenuation. In 1999, the U.S. Navy planted two hybrid poplar plantations, referred to as the northern and southern plantations, over the most contaminated parts of the landfill. The U.S. Navy monitors tree health, groundwater levels, and contaminant concentrations to assess the effectiveness of phytoremediation. The U.S. Geological Survey began a cooperative effort with the U.S. Navy in 1995 to monitor the effectiveness of natural attenuation processes for removing and controlling the migration of chloroethenes and chloroethanes. Field and laboratory studies from 1996 through 2000 demonstrated that biodegradation of chloroethenes and chloroethanes in shallow groundwater at OU 1 was substantial. The U.S. Geological Survey monitored geochemical and contaminant concentrations in groundwater annually from 2001 through 2010. This report presents groundwater geochemical and contaminant data collected by the U.S. Geological Survey during June 2010 and evaluates evidence for continued biodegradation of chloroethenes in groundwater. Geochemical and contaminant concentration data through 2010 indicate that biodegradation of chloroethenes in groundwater continued beneath the landfill at OU 1. Contaminant concentrations in groundwater decreased beneath most of the 9-acre landfill between 1999 and 2010. The evidence indicating that biodegradation was a primary cause for the decreased concentrations included decreasing ratios of more highly chlorinated compounds to less chlorinated compounds over time, and widespread detections of non-chlorinated biodegradation end-products ethane and ethene. No widespread changes in groundwater reduction-oxidation (redox) conditions were observed that could result in either more or less efficient biodegradation. Even with continued biodegradation, dissolved-phase contaminant concentrations in the tens of milligrams per liter have persisted beneath part of the 0.7-acre southern plantation. The magnitude and persistence of those concentrations indicate that non-aqueous phase liquid chloroethenes likely are present beneath the southern plantation and are not substantially affected by biodegradation. During 2010, chloroethenes continued to be measured in shallow groundwater samples from the southern part of the adjacent marsh, although at the lowest concentrations ever measured. Flux calculations based on 2010 data indicate that 95 percent of dissolved-phase chloroethenes in the upper aquifer beneath the southern landfill were degraded before discharging to surface water. Overall, biodegradation of chloroethenes in groundwater throughout OU 1 continued through 2010, and it prevented most of the mass of dissolved-phase chloroethenes in the upper aquifer beneath the landfill from discharging to surface water.

Washington↗
USGS1971

Analysis of current-meter data at Columbia River gaging stations, Washington and Oregon

The U.S. Geological Survey developed equipment to measure stream velocity simultaneously with 10 current meters arranged in a vertical and to measure velocity closer to the streambed than attainable with conventional equipment. With the 10 current meters, synchronous velocities were recorded for a period of 66 minutes at 10 different depths in one vertical of one gaging-station cross section. In addition, with a current meter installed on a special bracket to allow measurements to 0.5 foot above streambed, data were obtained at two to four verticals in four gaging-station cross sections. The mean velocity determined for the 66-minute period of record was 3.30 fps (feet per second). The graphic record of velocity was analyzed on a minute-by-minute basis. It was noted that the shape of the vertical velocity curves (plot of horizontal flow velocities measured in a vertical) changed from one minute to the next, but the change seemed to be random. Velocities obtained at different depths in the, profile fluctuated significantly, with the 1-minute velocities obtained at 0.05 depth (5 percent of total depths measured from the surface at indicated vertical) showing the smallest range--0.66 fps--and those at 0.55 depth the largest range--l.22 fps. The standard deviation, expressed in feet per second, of the velocity at each point in the vertical tended to increase with depth--from 0.16 fps at 0.05 depth to a maximum of 0.24 fps at 0.75 depth. The standard deviation, expressed as a percentage of the mean velocity, ranged from about 4 percent near the surface to 11 percent at 0.95 depth. In spite of the fluctuation in mean velocity that occurred during the 66 minutes and observation period of 4 minutes yields a mean velocity that differs from the 66-minute mean by less than one-half of a percent. Determining the mean velocity by averaging the 10-point observations of the 66minute run proved to be as accurate as by plotting the vertical velocity curvy (from the averaged 10 points) and then integrating the depth-velocity profile. In comparing the velocity obtained by integrating the depth-velocity profile with the 10-point mean velocity for other field data, collected beyond that obtained during the 66-minute run, the difference ranged from -1.3 to +1.7 percent and averaged -0.2 percent. Extension of the curve below the 0.95 depth by use of a power function proved to be fairly accurate (when compared with actual measurements within this reach made with the special current-meter bracket). However, the extension did not improve significantly the accuracy of the integrated-curve mean velocity. Both the one- and two-point methods were found to agree with the 10-point velocity. In computing mean river velocity, values determined by the two-point method ranged from -1.4 to +1.6 percent when compared with the base integrated-curve mean river velocity. The one-point method yielded results that ranged from -1.9 to +4.4 percent and averaged 40.1 percent. In determining river flow by use of the midsection and mean-section methods, the mean-section method uniformly yields lower flows for the same dart.. The range in difference is from -0.2 percent to -1.6 percent, with an average difference of -0.6 percent.

Water Supply Paper↗
USGS2012

Geologic map of the east half of the Bellevue South 7.5' x 15' quadrangle, Issaquah area, King County, Washington

The Issaquah area includes several of the most outstanding geologic features of the eastern Puget Lowland region. Folds have warped thousands of meters of Tertiary sedimentary and volcanic rocks. Several hundred meters of both glacial and postglacial sediment have accumulated in a deep glacial trough, which is now partly occupied by Lake Sammamish but which was previously the conduit for massive volumes of meltwater during ice-sheet occupation and retreat. The eastern projection of an east-west-oriented crustal structure, which reflects Tertiary through Holocene fault displacement, extends across the eastern part of the map area. In addition to these geologic features, some of the most rapid human alteration of the landscape in the entire Puget Lowland has occurred here. Since the 19th century, coal was extensively mined and, since the early 1980s, the region has been overtaken by urbanization. In places, this alteration has dramatically accelerated the rate of geomorphic processes. For example, the hillsides have been regraded as a result of mining and quarries throughout the southern one-third of the quadrangle; stream channels have recently incised above the eastern shores of Lake Sammamish; and sediments have deposited on the lakeshore and into the lake itself.

Washington↗
USGS1999

A Topographic Field Trip of Washington, D.C. - A Cartographic Multimedia Application

The U.S. Geological Survey (USGS) has produced ?A Topographic Field Trip of Washington, D.C.,' a multimedia CD-ROM that uses topographic maps to tour Washington, D.C. Although designed for the middle school grade level, it can also be used to teach introductory topographic map reading skills to any level. Two versions of ?A Topographic Field Trip of Washington, D.C.,? are available. The first version, for Macintosh? systems only, was developed and produced as a prototype with educational resources funds and is available free of charge. The second version, for dual platforms, Macintosh?, and Windows? systems, is a sales item. The dual platform version contains improvements in content and navigational capabilities.

Fact Sheet↗
USGS2015

Geologic map of the Vashon 7.5' quadrangle and selected areas, King County, Washington

This map is an interpretation of a 6-ft-resolution lidar-derived digital elevation model combined with geology by Derek B. Booth and Kathy Goetz Troost. Field work by Booth and Troost was located on the 1:24,000-scale topographic map of the Vashon and Des Moines 7.5' quadrangles that were published in 1997 and 1995, respectively. Much of the geology was interpreted from landforms portrayed on the topographic maps, supplemented by field exposures, where available. In 2001, the Puget Sound Lidar Consortium (see http://pugetsoundlidar.org/) obtained a lidar-derived digital elevation model (DEM) for Vashon Island and the Des Moines quadrangle. For a brief description of lidar and this data acquisition program, see Haugerud and others (2003). This new DEM has a horizontal resolution of 6 ft (1.83 m) and mean vertical accuracy of about 1 ft (about 0.3 m). The greater resolution and accuracy of the lidar DEM facilitated a much-improved interpretation of many aspects of the surficial geology, especially the distribution and relative age of landforms and the materials inferred to comprise them. Booth and Troost were joined by Tabor to interpret the new lidar DEM but have done no futher field work for this map. This map, the Vashon quadrangle and selected adjacent areas, encompasses most of Vashon Island, Maury Island, and Three Tree Point in the south-central Puget Sound. One small area in the Vashon quadrangle on the east side of Puget Sound is excluded from this map but included on the adjacent Seattle quadrangle (Booth and others, 2005). The map displays a wide variety of surficial geologic deposits, which reflect many geologic environments and processes. Multiple ice-sheet glaciations and intervening nonglacial intervals have constructed a complexly layered sequence of deposits that underlie both islands to a depth of more than 300 m below sea level. These deposits not only record glacial and nonglacial history but also control the flow and availability of ground water, determine the susceptibility of the slopes to landslides, and provide economic reserves of sand and gravel. The islands are surrounded by channels of Puget Sound, some as deep as the islands are high (>600 ft (~200 m)). The shorelines provide many kilometers of well-exposed coastal outcrops that reveal abundant lithologic and stratigraphic details not ordinarily displayed in the heavily vegetated Puget Lowland.

Washington↗
USGS2010

Occurrence and Distribution of Organic Wastewater Compounds in Rock Creek Park, Washington, D.C., 2007-08

The U.S. Geological Survey, and the National Park Service Police Aviation Group, conducted a high-resolution, low-altitude aerial thermal infrared survey of the Washington, D.C. section of Rock Creek Basin within the Park boundaries to identify specific locations where warm water was discharging from seeps or pipes to the creek. Twenty-three stream sites in Rock Creek Park were selected based on the thermal infrared images. Sites were sampled during the summers of 2007 and 2008 for the analysis of organic wastewater compounds to verify potential sources of sewage and other anthropogenic wastewater. Two sets of stormwater samples were collected, on June 27-28 and September 6, 2008, at the Rock Creek at Joyce Road water-quality station using an automated sampler that began sampling when a specified stage threshold value was exceeded. Passive-sampler devices that accumulate organic chemicals over the duration of deployment were placed in July 2008 at the five locations that had the greatest number of detections of organic wastewater compounds from the June 2007 base-flow sampling. During the 2007 base-flow synoptic sampling, there were ubiquitous low-level detections of dissolved organic wastewater indicator compounds such as DEET, caffeine, HHCB, and organophosphate flame retardants at more than half of the 23 sites sampled in Rock Creek Park. Concentrations of DEET and caffeine in the tributaries to Rock Creek were variable, but in the main stem of Rock Creek, the concentrations were constant throughout the length of the creek, which likely reflects a distributed source. Organophosphate flame retardants in the main stem of Rock Creek were detected at estimated concentrations of 0.2 micrograms per liter or less, and generally did not increase with distance downstream. Overall, concentrations of most wastewater indicators in whole-water samples in the Park were similar to the concentrations found at the upstream sampling station at the Maryland/District of Columbia boundary. Polycyclic aromatic hydrocarbons were the dominant organic compounds found in the stormwater samples at the Joyce Road station. Polycyclic aromatic hydrocarbons were consistently found in higher concentrations either in sediment or in whole-water samples than in the dissolved samples collected during base-flow conditions at the 23 synoptic sites, or in the Joyce Road station stormwater samples.

Scientific Investigations Report↗
USGS2007

Re-Evaluation of the 1921 Peak Discharge at Skagit River near Concrete, Washington

The peak discharge record at the U.S. Geological Survey (USGS) gaging station at Skagit River near Concrete, Washington, is a key record that has come under intense scrutiny by the scientific and lay person communities in the last 4 years. A peak discharge of 240,000 cubic feet per second for the flood on December 13, 1921, was determined in 1923 by USGS hydrologist James Stewart by means of a slope-area measurement. USGS then determined the peak discharges of three other large floods on the Skagit River (1897, 1909, and 1917) by extending the stage-discharge rating through the 1921 flood measurement. The 1921 estimate of peak discharge was recalculated by Flynn and Benson of the USGS after a channel roughness verification was completed based on the 1949 flood on the Skagit River. The 1949 recalculation indicated that the peak discharge probably was 6.2 percent lower than Stewart's original estimate but the USGS did not officially change the peak discharge from Stewart's estimate because it was not more than a 10-percent change (which is the USGS guideline for revising peak flows) and the estimate already had error bands of 15 percent. All these flood peaks are now being used by the U.S. Army Corps of Engineers to determine the 100-year flood discharge for the Skagit River Flood Study so any method to confirm or improve the 1921 peak discharge estimate is warranted. During the last 4 years, two floods have occurred on the Skagit River (2003, 2006) that has enabled the USGS to collect additional data, do further analysis, and yet again re-evaluate the 1921 peak discharge estimate. Since 1949, an island/bar in the study reach has reforested itself. This has complicated the flow hydraulics and made the most recent recalculation of the 1921 flood based on channel roughness verification that used 2003 and 2006 flood data less reliable. However, this recent recalculation did indicate that the original peak-discharge calculation by Stewart may be high, and it added to a body of evidence that indicates a revision in the 1921 peak discharge estimate is appropriate. The USGS has determined that a lower peak-discharge estimate (5.0 percent lower) similar to the 1949 estimates is most appropriate based on (1) a recalculation of the 1921 flood using a channel roughness verification from the 1949 flood data, (2) a recalculation of the 1921 flood using a channel roughness verification from 2003 and 2006 flood data, and (3) straight-line extension of the stage-discharge relation at the gage based on current-meter discharge measurements. Given the significance of the 1921 flood peak, revising the estimate is appropriate even though it is less than the 10-percent guideline established by the USGS for revision. Revising the peak is warranted because all work subsequent to 1921 point to the 1921 peak being lower than originally published.

Scientific Investigations Report↗