Performance evaluation of five turbidity sensors in three primary standards
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Water temperature is a basic, but important, measure of the condition of all aquatic environments, including the flowing waters in the streams that drain our landscape and the receiving waters of those streams. Climatic conditions have a strong influence on water temperature, which is therefore naturally variable both in time and across the landscape. Changes to natural water-temperature regimes, however, can result in a myriad of effects on aquatic organisms, water quality, circulation patterns, recreation, industry, and utility operations. For example, most species of fish, insects, and other organisms, as well as aquatic vegetation, are highly dependent on water temperature. Warming waters can result in shifts in floral and faunal species distributions, including invasive species and pathogens previously unable to inhabit the once cooler streams. Many chemical processes are temperature dependent, with reactions occurring faster in warmer conditions, leading to degraded water quality as contaminants are released into waterways at greater rates. Circulation patterns in receiving waters, such as bays and estuaries, can change as a result of warmer inflows from streams, thereby affecting organisms in those receiving waters. Changes in abundance of some aquatic species and (or) degradation of water quality can reduce the recreational value of water bodies as waters are perceived as less desirable for water-related activities or as sportfish become less available for anglers. Finally, increasing water temperatures can affect industry and utilities as the thermal capacity is reduced, making the water less effective for cooling purposes. Chesapeake Bay is the largest estuary in the United States. Eutrophication, the enrichment of a water body with excess nutrients, has plagued the bay for decades and has led to extensive restoration efforts throughout the bay watershed. The warming of stream water can exacerbate eutrophication through increased release of nutrients from in-stream sediments, so understanding changes in stream-water temperature throughout the bay watershed is critical to resource managers seeking to restore the bay ecosystem. The U.S. Environmental Protection Agency (EPA) uses indicators that “represent the state or trend of certain environmental or societal conditions … to track and better understand the effects of changes in the Earth’s climate” (U.S. Environmental Protection Agency, 2014). Updates to these indicators are published biennially by the EPA. The U.S. Geological Survey (USGS), in cooperation with the EPA, has completed analyses of air- and stream-water-temperature trends in the Chesapeake Bay region to be included as an indicator in a future release of the EPA report.
The Airborne Lidar Processing System (ALPS) analyzes Experimental Advanced Airborne Research Lidar (EAARL) data—digitized laser-return waveforms, position, and attitude data—to derive point clouds of target surfaces. A full-waveform airborne lidar system, the EAARL seamlessly and simultaneously collects mixed environment data, including submerged, sub-aerial bare earth, and vegetation-covered topographies. ALPS uses three waveform target-detection algorithms to determine target positions within a given waveform: centroid analysis, leading edge detection, and bottom detection using water-column backscatter modeling. The centroid analysis algorithm detects opaque hard surfaces. The leading edge algorithm detects topography beneath vegetation and shallow, submerged topography. The bottom detection algorithm uses water-column backscatter modeling for deeper submerged topography in turbid water. The report describes slant range calculations and explains how ALPS uses laser range and orientation measurements to project measurement points into the Universal Transverse Mercator coordinate system. Parameters used for coordinate transformations in ALPS are described, as are Interactive Data Language-based methods for gridding EAARL point cloud data to derive digital elevation models. Noise reduction in point clouds through use of a random consensus filter is explained, and detailed pseudocode, mathematical equations, and Yorick source code accompany the report.
The U.S. Geological Survey, in cooperation with the Upper Gunnison River Water Conservancy District, studied historical streamflow in a reach of the East River, Colorado, to gain a preliminary understanding of return flow dynamics. Return flow is agricultural irrigation water that is not consumed by evapotranspiration and instead reaches streams by surface and subsurface flow paths. The study reach had a contributing area of 50 square miles and contained 5.23 square miles of pastures irrigated with water diverted from the East River and its tributaries. By comparing upstream inflows to downstream outflows, the net water balance of the study reach from 1994 to 2023 was assessed. Two general hydrologic conditions for the study reach were identified. One hydrologic condition was characterized by a net loss or consumption of water, termed here as general deficit. This general deficit condition extended about 16 years, from 1997 to 2012. During general deficit years, there was usually a notable net loss of streamflow from April through July, and a small net gain, possibly related to return flows, occurred in August about 75 days after the minimums for losses. The second hydrologic condition was characterized by a net gain of water, termed here as general surplus. This second condition extended about 10 years, from 2014 to 2023. During general surplus years, two separate transitions from net loss to net gain commonly occurred during June through August. Losses during general surplus years were smaller than losses during general deficit years, the respective gains were larger, and times between losses and gains were about 18 and 22 days. Differences between the two hydrologic conditions could reflect interactions among irrigation water, available capacity to store additional shallow groundwater, and streamflow. However, deciphering the causes for the shifts between the two general hydrologic conditions was beyond the scope of this report.
Base maps compiled by Soil Conservation Service, U.S. Department of Agriculture. These maps are compilations of photogeology and surface geology, Colorado Plateau area, United States. They are also known as: Trace Elements Memorandum Report 399 (Verdure 1) Trace Elements Memorandum Report 406 (Verdure 2) Trace Elements Memorandum Report 438 (Verdure 4) Trace Elements Memorandum Report 405 (Verdure 6) Trace Elements Memorandum Report 395 (Verdure 7) Trace Elements Memorandum Report 403 (Verdure 8)
This report is one of several that are being made by the United States Geological Survey as part of the program of the Department of the Interior for the control, conservation, development, and use of the water resources of the Missouri River basin. The purpose of this report is to present an annotated bibliography of all existing reports pertaining to ground-water supplies in the area reported upon; to collect and analyze all data on public, industrial, and irrigation pumping from wells that are not covered by previous reports; to indicate areas where additional large-scale pumping might be undertaken; to estimate the possibility of depletion of stream flow by ground-water pumping from the developed areas and from areas where large-scale pumping maybe undertaken in the future; to point out areas where aquifers might be artificially recharged; and to recommend areas where detailed ground-water studies should be made, indicating the studies needed. The writer spent approximately 2 weeks in the field during June 1952 evaluating the results of previous studies to determine their adequacy with respect to the purpose of this report. It was found that the previous studies in the area adequately covered the ground-water conditions for this purpose; consequently, the following discussion is abstracted largely from reports covering those studies.
The purpose of this investigation which is being made in cooperation with the Georgia Department of Mines, Mining and Geology, Chatham County, and the City of Savannah, is to determine whether salt-water encroachment has occurred in the principal limestone aquifer in the Savannah area, and, if so, to delimit the extent of the encroachment vertically and laterally. The drilling of two test wells, which constitutes the initial part of the investigation, was done in April, May, and June, 1954. This interim report describes the subsurface geology in the Savannah area and reports the results of water samples taken during the test drilling. The investigation is being continued by M. A. Warren and F. B. Hudson of the U.S. Geological Survey, and later results will be given in a subsequent report.
This report on the floods of September and and October 1955 in the Nueces, Brazos, and Pecos River basins, Texas, was prepared in the Texas District Office, Surface Water Branch, under the direction of Trigg Twichell, District Engineer. Records of discharge were collected and compiled in cooperation with the Texas State Board of Water Engineers, the Pecos River Commission, and other agencies. The isohyetal map of the upper Brazos River basin, which was the basis for figure 4, was furnished by the Corps of Engineers. The "bucket" survey of rainfall in the Nueces River basin was conducted by the U.S. Weather Bureau, and the "bucket" survey in the upper Brazos River basin was conducted by the U.S. Weather Bureau, the Corps of Engineers, and the U.S. Soil Conservation Service. The U.S. Conservation Service furnished "A Report describing the effects of the storm of September 23-25, 1955, on the Upper Brazos River Watershed, above Possum Kingdom Dam" from which some data in this report were taken.
The Turle Lake quadrangle is in northeastern Washington about twenty-five miles west of Spokane. The present study includes slightly more than the southern half of the quadrangle. This study is the first detailed study of the rocks in this vicinity; earlier work in the area consists of reconnaissance mapping north of the quadrangle and reports on individual mines.
Numerous samples of plutonic rocks collected during reconnaissance mapping in western Alaska have been analyzed for K, U, and Th. The U and Th content of the plutonic rocks from the southeastern Seward Peninsula have been discussed in a separate report (Miller and Bunker, 1975); because of the current interest in U and Th, the analyses of the remaining samples are given in this report.
Reconnaissance geochemical sampling has been conducted by the Lithium Resource Program of the United States Geological Survey for much of the Western U.S. Sediment, rock, and brine samples have been collected in many states, but this report describes just those solid samples collected in Nevada. Further reports by other members of the Lithium Program will describe water samples from Nevada and samples from other states. The purpose of the sampling program was to determine if areas of anonalous lithium could be recognized by reconnaissance surface sampling. The results, however, have been indeterminate because most large lithium deposits occur at depth and appear to be formed when deeply buried. Many may not manifest themselves at the surface at all . Nonetheless, the data derived during the surface sampling program will be presented in this report.
An improved 4-channel electrical resistivity well-logging system for use with a passive probe with electrodes arranged in the 'normal' configuration has been designed and fabricated by Westinghouse Electric Corporation to meet technical specifications developed by the U.S. Geological Survey. Salient features of the system include solid-state switching and current regulation in the transmitter circuit to produce a constant-current source square wave, and synchronous solid-state switching and sampling of the potential waveform in the receiver circuit to provide an analog dc voltage proportions to the measured resistivity. Technical specifications and design details are included in this report.
During gas and oil exploration efforts in the Washakie Basin in Sweetwater County, Wyoming, undertaken by Ladd Petroleum Co. (a subsidiary of Utah International Inc.) core from the Upper Cretaceous Almond Formation of the Mesaverde Group was collected from their 1-22 Federal well. (See figure 1 for location.) From this core three coal and two carbonaceous shale samples, orginally at depths ranging from 3,091 to 3,116 m (see table 1 for descriptions), were selected and given to the U.S. Geological Survey for study. Results of chemical analyses on the samples and a comparison of these analyses with analyses of near-surface Almond Formation coal samples in Carbon County, Wyoming, are the topics of this report.
One hundred forty seven water samples were corrected from the Elkhorn Wilderness during the summer of 1977 as a part of a mineral resource assessment study. Each sample was analyzed for uranium. Specific conductance and pH were also measured. Sample analyses and site locations are presented in this report.
Basic data on the physical and chemical properties of San Francisco Bay waters are presented here. Samples were collected over the period March-November 1977 at approximately monthly intervals at 36 stations. The stations were located along the axis of the Bay from Calaveras Point in South San Francisco Bay to the town of Rio Vista on the Sacramento River. The samples were analyzed for the following core parameters: salinity, temperature, light transmission, chlorophyll a fluorescence, light extinction, turbidity, dissolved oxygen, pH, pCO 2 , orthophosphate, nitrate+nitrite, nitrite, ammonia, and silicate. Additional analyses were performed on selected discrete samples collected for particulate organic carbon, chlorophyll a, alkalinity, total CO 2 and suspended particulate matter. The results of these analyses and the analytical methods used are documented in this report.
The volcanic eruptions of Mount St. Helens have resulted in the collection of many forms of hydrologic data. Chemical data collected from March 27 to September 30, 1980, to document the effects of the various volcanic events (mudflows, pyroclastic flows, deposition of ash) on the quality of surface water at selected sites in the State of Washington are presented in the report. (USGS)
This report contains data on the physical and chemical properties measured during the 1979 water year for the tidal Potomac River and estuary. Data were collected routinely at five major stations and periodically at 14 intervening stations. Each major station represents a cross section through which the transport of selected dissolved and suspended materials will be computed. The intervening stations represent locations at which data were collected for special studies such as: salt water migration, dissolved oxygen dynamics, and other synoptic studies. About 960 samples were analyzed for silicate, Kjeldhal nitrogen, nitrite, phosphorus, chlorophyll and suspended sediment, with additional samples analyzed for organic carbon, calcium, magnesium, sodium, bicarbonate, sulfate, potassium, chloride, fluoride, seston and dissolved solids residue. In addition, about 1400 in-situ measurements of dissolved oxygen, specific conductance, temperature, and Secchi disk transparency are reported.
This manual contains analytical methods used by the U.S. Geological Survey for the determination of organic substances in water, water-suspended sediment mixtures, and bottom material. Some of the analytical procedures yield determinations for specific compounds, whereas others provide a measure of the quantity of groups of compounds present in the sample. Examples of the first category are procedures for the organochlorine and organophosphate insecticides, chlorophenoxy acid and triazine herbicides and specific substituted phenols. Examples of the second category are the various organic carbon analyses and the polychlorinated biphenyl methods. Each analytical method is presented in a standardized format which includes conditions for application of the method, a summary of the method, interferences, required apparatus and reagents, analytical procedures, calculations, reporting of results, and estimation of precision.