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At least 109 records · Page 6Linked to original sources
USGS2008

Simulation of Flood Profiles for Catoma Creek near Montgomery, Alabama, 2008

A one-dimensional step-backwater model was used to simulate flooding conditions for Catoma Creek near Montgomery, Alabama. A peak flow of 50,000 cubic feet per second was computed by the U.S. Geological Survey for the March 1990 flood at the Norman Bridge Road gaging station. Using this estimated peak flow, flood-plain surveys with associated roughness coefficients, and surveyed high-water marks for the March 1990 flood, a flow model was calibrated to closely match the known event. The calibrated model then was used to simulate flooding for the 10-, 50-, 100-, and 500-year recurrence-interval floods. The 100-year flood stage for the Alabama River also was computed in the vicinity of the Catoma Creek confluence using observed high-water profiles from the 1979 and 1990 floods and gaging-station data. The results indicate that the 100-year flood profile for Catoma Creek within the 15-mile study reach is about 2.5 feet higher, on average, than the profile published by the Federal Emergency Management Agency. The maximum and minimum differences are 6.0 feet and 0.8 foot, respectively. All water-surface elevations computed for the 100-year flood are higher than those published by the Federal Emergency Management Agency. The 100-year flood stage computed for the Alabama River in the vicinity of the Catoma Creek confluence was about 4.5 feet lower than the elevation published by the Federal Emergency Management Agency. The results of this study provide the community with flood-profile information that can be used for flood-plain mitigation, future development, and safety plans for the city.

Scientific Investigations Report↗
USGS2006

Guidelines and standard procedures for continuous water-quality monitors: Station operation, record computation, and data reporting

The U.S. Geological Survey uses continuous water-quality monitors to assess the quality of the Nation's surface water. A common monitoring-system configuration for water-quality data collection is the four-parameter monitoring system, which collects temperature, specific conductance, dissolved oxygen, and pH data. Such systems also can be configured to measure other properties, such as turbidity or fluorescence. Data from sensors can be used in conjunction with chemical analyses of samples to estimate chemical loads. The sensors that are used to measure water-quality field parameters require careful field observation, cleaning, and calibration procedures, as well as thorough procedures for the computation and publication of final records. This report provides guidelines for site- and monitor-selection considerations; sensor inspection and calibration methods; field procedures; data evaluation, correction, and computation; and record-review and data-reporting processes, which supersede the guidelines presented previously in U.S. Geological Survey Water-Resources Investigations Report WRIR 00-4252. These procedures have evolved over the past three decades, and the process continues to evolve with newer technologies.

Techniques and Methods↗
USGS2021

Assessment of water quality and discharge in the Herring River, Wellfleet, Massachusetts, November 2015 to September 2017

The U.S. Geological Survey, Cape Cod National Seashore of the National Park Service, and Friends of Herring River cooperated from 2015 to 2017 to assess nutrient concentrations and fluxes across the ocean-estuary boundary at a dike on the Herring River in Wellfleet, Massachusetts. The purpose of this assessment was to characterize environmental conditions prior to a future removal of the dike, which has restricted saltwater inputs into the Herring River watershed for more than 100 years. Water temperature, dissolved oxygen, pH, and specific conductance were monitored continuously, and flow-weighted composite samples were collected approximately twice per month at the ocean-estuary boundary. Bidirectional discharge was computed for the U.S. Geological Survey Herring River at Chequessett Neck Road at Wellfleet, Massachusetts, streamgage (011058798) by using a stage-area rating and index-velocity ratings developed with acoustic Doppler current profile measurements made upstream and downstream from the dike. LOADEST regression modeling software was used to estimate nutrient fluxes (loads) from composite, paired nutrient concentration and discharge data in conjunction with continuous discharge data. Temperature, dissolved oxygen, pH, and specific conductance were also monitored continuously on two tributaries to the Herring River, Pole Dike Creek and Bound Brook, from late-May 2016 to mid-June 2017. Composite or discrete water samples were collected from the tributaries approximately twice per month in most months from late-May 2016 to mid-June 2017 and analyzed for total nitrogen, total phosphorus, and dissolved organic carbon. Flow-weighted concentrations of ammonium, nitrate, and total nitrogen on the Herring River at the dike on the ebb tide generally varied between 0.01 and 0.1, 0.003 and 0.03, and 0.3 and 0.7 milligram per liter as nitrogen, respectively. Flow-weighted concentrations of orthophosphate, total dissolved phosphorus, and total phosphorus generally varied between 0.002 and 0.02, 0.003 and 0.06, and 0.03 and 0.1 milligram per liter as phosphorus, respectively, on the ebb tide. Flow-weighted concentrations of silicate and dissolved organic carbon on the ebb tide generally varied between 0.08 and 3.0 milligrams per liter of silica (silicon dioxide), and 1.7 and 5.6 milligrams per liter of carbon, respectively. Ebb tide concentrations of nitrate were highest in winter and lowest in summer. By contrast, ebb tide concentrations of phosphorus species were highest in late summer and early fall and lowest in winter. Silica and dissolved organic carbon did not exhibit systematic variation in seasonal concentrations. There was uncertainty in estimates of nutrient fluxes, but the LOADEST-estimated fluxes indicated that annual (and in almost all cases seasonal) exports (ebb tides) exceeded inputs (flood tides). Ebb tide concentrations of ammonium, nitrate, total nitrogen, and silica were positively correlated with antecedent cumulative 7-day precipitation.

Massachusetts↗
USGS2007

Simulation of Flood Profiles for Fivemile Creek at Tarrant, Alabama, 2006

A one-dimensional step-backwater model was used to simulate flooding conditions for Fivemile Creek at Tarrant, Alabama. The 100-year flood stage published in the current flood insurance study for Tarrant by the Federal Emergency Management Agency was significantly exceeded by the March 2000 and May 2003 floods in this area. A peak flow of 14,100 cubic feet per second was computed by the U.S. Geological Survey for the May 2003 flood in the vicinity of Lawson Road. Using this estimated peak flow, flood-plain surveys with associated roughness coefficients, and the surveyed high-water profile for the May 2003 flood, a flow model was calibrated to closely match this known event. The calibrated model was then used to simulate flooding for the 10-, 50-, 100-, and 500-year recurrence interval floods. The results indicate that for the 100-year recurrence interval, the flood profile is about 2.5 feet higher, on average, than the profile published by the Federal Emergency Management Agency. The absolute maximum and minimum difference is 6.80 feet and 0.67 foot, respectively. All water-surface elevations computed for the 100-year flood are higher than those published by the Federal Emergency Management Agency, except for cross section H. The results of this study provide the community with flood-profile information that can be used for existing flood-plain mitigation, future development, and safety plans for the city.

Open-File Report↗
USGS2024

Total phosphorus and suspended-sediment concentrations and loads from two main tributaries to Upper Klamath Lake, Oregon, 2014–20

Total phosphorus (TP) and suspended-sediment concentrations (SSC) and loads were computed at two U.S. Geological Survey (USGS) streamgages in the upper Klamath River Basin on the Sprague (USGS site ID 11501000) and Williamson (USGS site ID 11502500) Rivers using high temporal resolution turbidity and streamflow data to develop surrogate regression models. Regression models were updated and validated for TP at the Williamson River site, and additional data improved a prior published TP model, increasing the coefficient of determination (R 2 ) from 0.73 to 0.88. A new TP regression model was developed for the Sprague River site using 2 years of data and showed promising results with an R 2 of 0.93. Suspended-sediment concentration (SSC) surrogate models were also updated at these sites using a longer period of record than the TP models and improved characterization of sediment transport conditions at these monitoring sites. Computations of TP loads were compared to the annual loading capacity dictated by the total maximum daily load (TMDL) for Upper Klamath Lake and showed that the combined TP load of the Williamson and Sprague Rivers approaches the annual loading capacity in water years with high annual streamflow. TP loads were also compared to loads computed by the Klamath Tribes using a long-term dataset and a regression and interpolation algorithm (RIA). The comparison showed that the two methods report similar annual loads, with the surrogate regression method generally reporting lower loads than the RIA, and the RIA annual loads falling within the range of uncertainty of the surrogate regression model results. Determining the effect of habitat and stream restoration on basin-scale TP and suspended-sediment loading is challenging using the surrogate regression method at these sites given the short period of record that TP and suspended-sediment load (SSL) data are available. However, long-term analysis by the Klamath Tribes in their larger monitoring network could provide insight into the impact of restoration at smaller spatial scales compared to the basin-wide assessment produced in this study.

Oregon↗
USGS1994

Water-surface profile and flood boundaries for the computed 100-year flood, Muddy Creek, Northern Cheyenne Indian Reservation, Montana

Hydrologic and hydraulic evaluations of Muddy Creek were made to determine the magnitude of the 100-year flood and the extent of flooding that would occur as the result of this flood. Forty-three cross sections were surveyed and 14 cross sections were synthesized along a 6.7-mile reach of Muddy Creek. Data from the surveys were used to calculate the water-surface flood elevation at each cross section using a computer program (WSPRO) developed by the U.S. Geological Survey. The water-surface profile of the computed 100-year flood elevations was then drawn. The profile shows the streambed elevation and the location of one bridge, one culvert, and cross sections. The computed 100-year flood elevation at each cross section was used to delineate the width of the flood plain at that section. Flood boundaries between cross sections were interpolated using contour lines on topographic maps.

Water-Resources Investigations Report↗
USGS1994

Water-surface profile and flood boundaries for the computed 100-year flood, Lame Deer Creek, Northern Cheyenne Indian Reservation, Montana

Hydrologic and hydraulic evaluations of Lame Deer Creek were made to determine the magnitude of the 100-year flood and the extent of flooding that would occur as the result of this flood. SixtY-six cross sections were Surveyed and 25 cross sections were synthesized along a 9.5-mile reach of Lame Deer Creek. Data from the surveys were used to calculate the water-surface elevation at each cross section using a computer program (WSPRO) developed by the U.S. Geological Survey. The water-surface profile of the computed 100-year flood elevations was then drawn. The profile shows the streambed elevation and the location of the bridge, culverts, and cross sections. The computed 100-year flood elevation at each cross section was used to delineate the width of the flood plain at that section. Flood boundaries between cross sections were interpolated using contour lines on topographic maps.

Water-Resources Investigations Report↗
USGS1995

Water-surface profile and flood boundaries for the computed 100-year flood, Rosebud Creek, Northern Cheyenne Indian Reservation, Montana

Hydrologic and hydraulic evaluations of Rosebud Creek were made to determine the magnitude of the 100-year flood and the extent of flooding that would occur as the result of this flood. The magnitude of the 100-year flood was determined to range from 2,620 to 3,980 ft3/s, depending on location. Field surveys were made at 149 cross sections along a 39-mile reach of Rosebud Creek. An additional 33 cross sections along the same reach were synthesized. Data from the surveys were used to calculate the water-surface elevation at each cross section using a computer program (WSPRO) developed by the U.S. Geological Survey. The water-surface profile of the computed 100-year flood elevations was then drawn. The profile also shows the streambed elevation and the location of the bridges and cross sections. The computed 100-year flood elevation at each cross section was used to delineate the width of the flood plain at that section. Flood boundaries between cross sections were interpolated using contour lines on topographic maps.

Water-Resources Investigations Report↗
USGS1996

Water-surface profile and flood boundaries for the computed 100-year flood, Big Muddy Creek, Fort Peck Indian Reservation and adjacent area, Montana

Hydrologic and hydraulic evaluations of Big Muddy Creek were made to determine the magnitude of the 100-year flood and the extent of flooding that would occur as the result of this flood. The magnitude of the 100-year flood was determined to range from 13,600 to 20,400 ft3/s, depending on location. Field surveys were made at 39 cross sections along a 41-mile reach of Big Muddy Creek. An additional two cross sections along the same reach were synthesized. Data from the surveys were used to calculate the water-surface elevation at each cross section using a computer program (WSPRO) developed by the U.S. Geological Survey. The water-surface profile of the computed 100-year flood elevations was then drawn. The profile also shows the streambed elevation and the location of the bridges and cross sections. The computed 100-year flood elevation at each cross section was used to delineate the width of the flood plain at that section. Flood boundaries between cross sections were interpolated using contour lines on topographic maps.

Water-Resources Investigations Report↗
USGS2007

Groundwater flow with energy transport and water-ice phase change: Numerical simulations, benchmarks, and application to freezing in peat bogs

In northern peatlands, subsurface ice formation is an important process that can control heat transport, groundwater flow, and biological activity. Temperature was measured over one and a half years in a vertical profile in the Red Lake Bog, Minnesota. To successfully simulate the transport of heat within the peat profile, the U.S. Geological Survey's SUTRA computer code was modified. The modified code simulates fully saturated, coupled porewater-energy transport, with freezing and melting porewater, and includes proportional heat capacity and thermal conductivity of water and ice, decreasing matrix permeability due to ice formation, and latent heat. The model is verified by correctly simulating the Lunardini analytical solution for ice formation in a porous medium with a mixed ice-water zone. The modified SUTRA model correctly simulates the temperature and ice distributions in the peat bog. Two possible benchmark problems for groundwater and energy transport with ice formation and melting are proposed that may be used by other researchers for code comparison.

Minnesota↗
USGS2003

Moment-tensor solutions estimated using optimal filter theory: Global seismicity, 2001

This paper is the 12th in a series published yearly containing moment-tensor solutions computed at the US Geological Survey using an algorithm based on the theory of optimal filter design ( Sipkin, 1982 and Sipkin, 1986b ). An inversion has been attempted for all earthquakes with a magnitude, m b or M S , of 5.5 or greater. Previous listings include solutions for earthquakes that occurred from 1981 to 2000 ( Sipkin, 1986b ; Sipkin and Needham, 1989 , Sipkin and Needham, 1991 , Sipkin and Needham, 1992 , Sipkin and Needham, 1993 , Sipkin and Needham, 1994a and Sipkin and Needham, 1994b ; Sipkin and Zirbes, 1996 and Sipkin and Zirbes, 1997 ; Sipkin et al., 1998 , Sipkin et al., 1999 , Sipkin et al., 2000a , Sipkin et al., 2000b and Sipkin et al., 2002 ). The entire USGS moment-tensor catalog can be obtained via anonymous FTP at ftp://ghtftp.cr.usgs.gov . After logging on, change directory to “momten”. This directory contains two compressed ASCII files that contain the finalized solutions, “mt.lis.Z” and “fmech.lis.Z”. “mt.lis.Z” contains the elements of the moment tensors along with detailed event information; “fmech.lis.Z” contains the decompositions into the principal axes and best double-couples. The fast moment-tensor solutions for more recent events that have not yet been finalized and added to the catalog, are gathered by month in the files “jan01.lis.Z”, etc. “fmech.doc.Z” describes the various fields.

Physics of the Earth and Planetary Interiors↗
USGS1982

Radiometric age file for Alaska: A section in The United States Geological Survey in Alaska: Accomplishments during 1980

The Alaska radiometric age file of the Branch of Alaskan Geology is a computer-based compilation of radiometric dates from the state of Alaska and the western parts of the Yukon Territory and British Columbia. More than 1800 age determinations from over 250 references have been entered in the file. References date back to 1958 and include both published and unpublished sources. The file is the outgrowth of an original radiometric age file compiled by Don Grybeck and students at the University of Alaska-Fairbanks (Turner and others, 1975).

Alaska↗
USGS1985

Data processing programs for aerial gamma-ray data

The U.S. Geological Survey (USGS) uses computer programs to process aerial gamma-ray data; some do editing and data manipulation to allow for corrections. Programs to convert flight-line data to latitude-longitude coordinates are included. Plotting programs include contour plotting, profile plots, and photographic raster plots.

Open-File Report↗
USGS1986

Identification and description of potential ground-water quality monitoring wells in Florida

The results of a survey of existing wells in Florida that meet the following criteria are presented: (1) well location is known , (2) principal aquifer is known, (3) depth of well is known, (4) well casing depth is known, (5) well water had been analyzed between 1970 and 1982, and (6) well data are stored in the U.S. Geological Survey 's (USGS) computer files. Information for more than 20,000 wells in Florida were stored in the USGS Master Water Data Index of the National Water Data Exchange and in the National Water Data Storage and Retrieval System 's Groundwater Site Inventory computerized files in 1982. Wells in these computer files that had been sampled for groundwater quality before November 1982 in Florida number 13,739; 1,846 of these wells met the above criteria and are the potential (or candidate) groundwater quality monitoring wells included in this report. The distribution by principal aquifer of the 1,846 wells identified as potential groundwater quality monitoring wells is as follows: 1,022 tap the Floridan aquifer system, 114 tap the intermediate aquifers, 232 tap the surficial aquifers, 246 tap the Biscayne aquifer, and 232 tap the sand-and-gravel aquifer. These wells are located in 59 of Florida 's 67 counties. This report presents the station descriptions, which include location , site characteristics, period of record, and the type and frequency of chemical water quality data collected for each well. The 1,846 well locations are plotted on 14 USGS 1:250,000 scale, 1 degree by 2 degree, quadrangle maps. This relatively large number of potential (or candidate) monitoring wells, geographically and geohydrologically dispersed, provides a basis for a future groundwater quality monitoring network and computerized data base for Florida. There is a large variety of water quality determinations available from these wells, both areally and temporally. Future sampling of these wells would permit analyses of time and areal trends for selected water quality characteristics throughout the State. The identification and description of the potential monitoring wells and the listing of the type and frequency of the groundwater quality data forms a foundation for both the network and the data base. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1961

Floods in the Skagit River basin, Washington

According to Indian tradition, floods of unusually great magnitude harassed the Skagit River basin about 1815 and 1856. The heights of these floods were not recorded at the time; so they are called historical floods. Since the arrival of white men about 1863, a number of large and damaging floods have been witnessed and recorded. Data concerning and verifying the early floods, including those of 1815 and 1856, were collected prior to 1923 by James E. Stewart. He talked with many of the early settlers in the valley who had listened to Indians tell about the terrible floods. Some of these settlers had referenced the maximum stages of floods they had witnessed by cutting notches at or measuring to high-water marks on trees. In order to verify flood stages Stewart spent many weeks finding and levelling to high-water marks such as drift deposits, sand layers in coves, and silt in the bark of certain types of trees. Gaging stations have been in operation at various locations on the Skagit River and its tributaries since 1909, so recorded peak stages are available at certain sites for floods occurring since that date. All peak discharge data available for both historical and recorded floods have been listed in this report. The types of floods as to winter and summer, the duration of peaks, and the effect of reservoirs are discussed. In 1899 Sterling Dam was constructed at the head of Gages Slough near Sedro Woolley. This was the beginning of major diking in the lower reaches of the Skagit River. Maps included in the report show the location of most of the dike failures that have occurred during the last 73 years and the area probably inundated by major floods. The damage resulting from certain floods is briefly discussed. The report is concluded with a brief discussion of the U.S. Geological Survey method of computing flood-frequency curves as applied to the Skagit River basin. The treatment of single-station records and a means of combining these records for expressing regional significance are exemplified. Historical data are used in the development of both the single-station and the regional curves.

Washington↗
USGS1981

Some thoughts on cartographic and geographic information systems for the 1980's

The U.S. Geological Survey is adopting computer techniques to meet the expanding need for cartographic base category data. Digital methods are becoming increasingly important in the mapmaking process, and the demand is growing for physical, social, and economic data. Recognizing these emerging needs, the National Mapping Division began, several years ago, an active program to develop advanced digital methods to support cartographic and geographic data processing. An integrated digital cartographic database would meet the anticipated needs. Such a database would contain data from various sources, and could provide a variety of standard and customized map and digital data file products. This cartographic database soon will be technologically feasible. The present trends in the economics of cartographic and geographic data handling and the growing needs for integrated physical, social, and economic data make such a database virtually mandatory.

Pecora VII Symposium↗