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At least 1,045 records · Page 58Linked to original sources
USGS1978

Water resources data for West Virginia, water year 1977

Water resources data for the 1977 water year for West Virginia consist of records of stage, discharge, and water quality of streams and springs; stage and contents of lakes and reservoirs; and water levels in wells. This report contains discharge records for 129 gaging stations; stage only records for 2 gaging stations; stage and contents for 7 lakes and reservoirs; contents for 1 reservoir; water quality for 43 gaging stations; and water levels for 36 observation wells. Also included are 35 crest-stage partial-record stations. Additional water data were collected at various sites, not part of the systematic data collections program, and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in West Virginia.

West Virginia↗
USGS1979

Water resources data for West Virginia, water year 1978

Water resources data for the 1978 water year for West Virginia consist of records of stage, discharge, and water quality of streams and springs; stage and contents of lakes and reservoirs; and water levels in wells. This report contains discharge records for 118 gaging stations; stage only records for 3 gaging stations; stage and contents for 7 lakes and reservoirs; contents for 1 reservoir; change in contents for 1 reservoir; water quality for 47 gaging stations; and water levels for 31 observation wells. Also included are 3 crest-stage partial-record stations, and 4 low-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data collections program, and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in West Virginia.

West Virginia↗
USGS1981

Water resources data for West Virginia, water year 1980

Water resources data for the 1980 water year for West Virginia consist of records of stage, discharge, and water quality of streams and springs; stage and contents of lakes and reservoirs; and water levels in wells. This report contains discharge records for 117 gaging stations; stage only records for 8 gaging stations; stage and contents for 8 lakes and reservoirs; contents for 1 reservoir; change in contents for 1 reservoir; water quality for 101 gaging stations; and water levels for 37 observation wells. Also included are 5 crest-stage partial-record stations, and 1 low-flow partial record station. Additional water data were collected at various sites, not part of the systematic data collections program, and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in West Virginia.

West Virginia↗
USGS1983

Water resources data West Virginia, water year 1982

Water resources data for the 1982 water year for West Virginia consist of records of stage, discharge, and water quality of streams and springs; stage and contents of lakes and reservoirs; and water levels in wells. This report contains discharge records for 116 gaging stations; stage only records for 9 gaging stations; stage and contents for 8 lakes and reservoirs; contents for 1 reservoir; change in contents for 1 reservoir; water quality for 55 gaging stations; and water levels for 29 observation wells. Also included are 2 crest-stage partial-record stations, and 1 low-flow partial record station. Additional water data were collected at various sites, not part of the systematic data collections program, and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal Agencies in West Virginia.

West Virginia↗
USGS1977

Water resources data, Wyoming, water year 1976; volume 1. Missouri River basin

Water resources data for the 1976 water year for Wyoming consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of wells. This report, in two volumes, contains discharge records for 226 gaging stations; stage only records for 1 lake; stage and contents for 16 lakes and reservoirs; water quality for 116 gaging stations, 68 ungaged stations, 4 lakes and reservoirs, and 253 wells and springs; and water levels for 48 observation wells. Also included are 111 crest-stage partial-record stations. Additional water data were collected at: various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming.

Wyoming↗
USGS1978

Water resources data for Wyoming, water year 1977; Volume 2. Green River basin; Bear River basin; Snake River basin

Water resources data for the 1977 water year for Wyoming consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of wells. This report, in two volumes, contains discharge records for 214 gaging stations; stage only records for 1 lake; stage and contents for 16 lakes and reservoirs; water quality for 117 gaging stations, 41 ungaged stations, 2 lakes and reservoirs, and 247 wells and springs; and water levels for 45 observation wells. Also included are 101 crest-stage partial-record stations. Additional water data were collected at various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming.

Wyoming↗
USGS1981

Water resources data, Wyoming, water year 1980: Volume 1. Missouri River basin

Water resources data for the 1980 water year for Wyoming consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of wells. Volume 1 of this report contains discharge records for 161 gaging stations; stage only records for 1 lake; stage and contents for 11 lakes and reservoirs; water quality for 93 gaging stations, 44 ungaged stations, 100 wells and springs; and water levels for 36 observation wells. Also included are 74 crest-stage partial-record stations and 2 precipitation monitoring sites. Additional water data were collected at various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements and analyses. This data represents that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming.

Wyoming↗
USGS1982

Water resources data, Wyoming, water year 1981: Volume 1. Missouri River basin

Water resources data for the 1981 water year for Wyoming consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. Volume 1 of this report contains discharge records for 155 gaging stations; stage only for records for 1 lake; stage and contents for 11 lakes and reservoirs; water quality for 89 gaging stations, and 45 ungaged stations; and water levels for 33 observation wells. Also included are 74 crest-stage partial-record stations and 2 precipitation monitoring sites. Additional water data were collected at various sies, not part of the systematic data collection program, and are published as miscellaneous measurements. These data together with the data in Volume 2 represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming.

Wyoming↗
USGS1983

Water resources data, Wyoming, water year 1982

Water resources data for the 1982 water year for Wyoming consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains discharge records for 185 gaging stations; stage only for records for 1 lake; stage and contents for 14 lakes and reservoirs; water quality for 85 gaging stations, and 61 ungaged stations; and water levels for 36 observation wells. Also included are 32 crest-stage partial-record stations and 1 precipitation monitoring site. Additional water data were collected at various sites, not part of the systematic data collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming.

Wyoming↗
USGS2003

Estimated flood-inundation maps for Cowskin Creek in western Wichita, Kansas

The October 31, 1998, flood on Cowskin Creek in western Wichita, Kansas, caused millions of dollars in damages. Emergency management personnel and flood mitigation teams had difficulty in efficiently identifying areas affected by the flooding, and no warning was given to residents because flood-inundation information was not available. To provide detailed information about future flooding on Cowskin Creek, high-resolution estimated flood-inundation maps were developed using geographic information system technology and advanced hydraulic analysis. Two-foot-interval land-surface elevation data from a 1996 flood insurance study were used to create a three-dimensional topographic representation of the study area for hydraulic analysis. The data computed from the hydraulic analyses were converted into geographic information system format with software from the U.S. Army Corps of Engineers' Hydrologic Engineering Center. The results were overlaid on the three-dimensional topographic representation of the study area to produce maps of estimated flood-inundation areas and estimated depths of water in the inundated areas for 1-foot increments on the basis of stream stage at an index streamflow-gaging station. A Web site (http://ks.water.usgs.gov/Kansas/cowskin.floodwatch) was developed to provide the public with information pertaining to flooding in the study area. The Web site shows graphs of the real-time streamflow data for U.S. Geological Survey gaging stations in the area and monitors the National Weather Service Arkansas-Red Basin River Forecast Center for Cowskin Creek flood-forecast information. When a flood is forecast for the Cowskin Creek Basin, an estimated flood-inundation map is displayed for the stream stage closest to the National Weather Service's forecasted peak stage. Users of the Web site are able to view the estimated flood-inundation maps for selected stages at any time and to access information about this report and about flooding in general. Flood recovery teams also have the ability to view the estimated flood-inundation map pertaining to the most recent flood. The availability of these maps and the ability to monitor the real-time stream stage through the U.S. Geological Survey Web site provide emergency management personnel and residents with information that is critical for evacuation and rescue efforts in the event of a flood as well as for post-flood recovery efforts.

Water-Resources Investigations Report↗
USGS1984

Evaluation of alternative reservoir-management practices in the Rock River basin, Wisconsin

Simulation of the operation of upstream impoundments in the Rock River basin to reduce spring floods showed that such operation would reduce flood peaks by 0.11 foot on the average, and would increase flood peaks some years. The most significant reductions would occur during the average- size floods, whereas little or no reductions would occur for larger and smaller floods. Modifying the simulation of impoundment operations to reduce larger floods produced only minor reductions in flood peaks for the larger floods, and slightly increased flood peaks for average-size floods. Alternative operating procedures for Indianford Dam which controls Lake Koshkonong were simulated with estimated power generation and the use of flashboards during the summer, neither of which are currently used. The simulation showed that, for most periods without significant runoff, the stage of Lake Koshkonong would tend toward the stage at which power generation was prohibited. It also showed that use of flashboards to raise the minimum lake stage during the summer would not raise the peak stage of the lake measurably if the flashboards were removed when the stage rose above its normal level. Simulation showed that winter drawdown of Lake Koshkonong would not lower spring flood peaks significantly downstream.

Wisconsin↗
USGS1985

A computer program for analyzing channel geometry

The Channel Geometry Analysis Program (CGAP) provides the capability to process, analyze, and format cross-sectional data for input to flow/transport simulation models or other computational programs. CGAP allows for a variety of cross-sectional data input formats through use of variable format specification. The program accepts data from various computer media and provides for modification of machine-stored parameter values. CGAP has been devised to provide a rapid and efficient means of computing and analyzing the physical properties of an open-channel reach defined by a sequence of cross sections. CGAP 's 16 options provide a wide range of methods by which to analyze and depict a channel reach and its individual cross-sectional properties. The primary function of the program is to compute the area, width, wetted perimeter, and hydraulic radius of cross sections at successive increments of water surface elevation (stage) from data that consist of coordinate pairs of cross-channel distances and land surface or channel bottom elevations. Longitudinal rates-of-change of cross-sectional properties are also computed, as are the mean properties of a channel reach. Output products include tabular lists of cross-sectional area, channel width, wetted perimeter, hydraulic radius, average depth, and cross-sectional symmetry computed as functions of stage; plots of cross sections; plots of cross-sectional area and (or) channel width as functions of stage; tabular lists of cross-sectional area and channel width computed as functions of stage for subdivisions of a cross section; plots of cross sections in isometric projection; and plots of cross-sectional area at a fixed stage as a function of longitudinal distance along an open-channel reach. A Command Procedure Language program and Job Control Language procedure exist to facilitate program execution on the U.S. Geological Survey Prime and Amdahl computer systems respectively. (Lantz-PTT)

Water-Resources Investigations Report↗
USGS1948

Texas floods of 1940

Floods occurred in Texas during, June, July, and November 1940 that exceeded known stages on many small streams and at a few places on the larger streams. Stages at several stream-gaging stations exceeded the maximum known at those places since the collection of daily records began. A storm, haying its axis generally on a north-south line from Cameron to Victoria and extending across the Brazos, Colorado, Lavaca, and Guadalupe River Basins, caused heavy rainfall over a large part of south-central Texas. The maximum recorded rain of 22.7 inches for the 2-day period June 29-30 occurred at Engle. Of this amount, 17.5 inches fell in the 12-hour period between 8 p.m. June 29, and 8 a.m. June 30. Light rains fell at a number of places on June 28, and additional light rains fell at many places within the area from July 1 to 4. During the period June 28 to July 4 more than 20 inches of rain fell over an area of 300 square miles, more than 15 inches over 1,920 square miles, and more than 10 inches over 5,100 square miles. The average annual rainfall for the area experiencing the heaviest rainfall during this storm is about 35 inches. Farming is largely confined to the fertile flood plains in much of the area subjected to the record-breaking floods in June and July. Therefore these floods, coming at the height of the growing season, caused severe losses to crops. Much damage was done also to highways and railways. The city of Hallettsville suffered the greatest damage of any urban area. The Lavaca River at that place reached a stage 8 feet higher than ever known before, drowned several people, destroyed many homes, and submerged almost the entire business district. The maximum discharge there was 93,100 second-feet from a drainage area of 101 square miles. Dry Creek near Smithville produced a maximum discharge of 1,879 second-feet from an area of 1.48 square miles and a runoff of 11.3 inches in a 2-day period from a rainfall of 19.5 inches. The area in the Colorado River Basin between Smithville and La Grange, amounting to 550 square miles, had an average rainfall of 19.3 inches, of which 11.5 inches appeared as runoff. The maximum discharge at La Grange was 182,000 second-feet, with much the greater part coming from below Smithville. This is probably a record-breaking flood for the area between Smithville and La Grange, but stages as much as 16 feet higher have occurred at La Grange. Heavy rainfall over the east half of Texas November 21-26 caused large floods in all streams in Texas east of the Guadalupe River. The maximum recorded rainfall for the 2-day period November 24-25 was 20.46 inches at Hempstead, of which 16.00 inches fell in 24 hours or less. The storm occurred during the period November 20-26, with the greater part of the rain falling November 23-25. During the period November 20-26, rainfall in Texas amounted to more than 15 inches over an area of 3,380 square miles, and 'to more than 10 inches over an area of 17,570 square miles. The average annual rainfall for the area in Texas experiencing more than 10 inches of rain during this storm ranges from 501 inches on the east border of the State to 35 inches near the west edge of the area. The study of this storm for the purposes of this report is limited to the San Jacinto River Basin, which had an average rainfall of 13.6 inches. This basin has an area of 2,791 square miles above the gaging station near Huffman and is typical in topographic and hydrologic features of much of eastern Texas. The stage reached at the gage near Huffman was about 1 foot higher than known before, the maximum discharge was 253,000 second-feet, and the runoff from the storm amounted to 8.8 inches. The November flood came after crops had been harvested, and its damage was mainly the destruction of highways and railways and the drowning of livestock. The storage reservoirs on the Colorado River located well upstream from the storm areas herein studied had very little effect on

Water Supply Paper↗
USGS2025

Perpetuation of avian influenza from molt to fall migration in wild Swan Geese (Anser cygnoides): An agent-based modeling approach

Wild waterfowl are considered to be the reservoir of avian influenza, but their distinct annual life cycle stages and their contribution to disease dynamics are not well understood. Studies of the highly pathogenic avian influenza (HPAI) virus have primarily focused on wintering grounds, where human and poultry densities are high year-round, compared with breeding grounds, where migratory waterfowl are more isolated. Few if any studies of avian influenza have focused on the molting stage where wild waterfowl congregate in a few selected wetlands and undergo the simultaneous molt of wing and tail feathers during a vulnerable flightless period. The molting stage may be one of the most important periods for the perpetuation of the disease in waterfowl, since during this stage, immunologically naïve young birds and adults freely intermix prior to the fall migration. Our study incorporated empirical data from virological field samplings and markings of Swan Geese ( Anser cygnoides ) on their breeding grounds in Mongolia in an integrated agent-based model (ABM) that included susceptible–exposed–infectious–recovered (SEIR) states. Our ABM results provided unique insights and indicated that individual movements between different molting wetlands and the transmission rate were the key predictors of HPAI perpetuation. While wetland extent was not a significant predictor of HPAI perpetuation, it had a large effect on the number of infections and associated death toll. Our results indicate that conserving undisturbed habitats for wild waterfowl during the molting stage of the breeding season could reduce the risk of HPAI transmission.

Viruses↗
USGS2019

Magmatic-hydrothermal gold mineralization at the Lone Tree Mine, Battle Mountain district, Nevada

The Lone Tree deposit is located in the northern Battle Mountain mining district, Nevada. Prior to mine closure in 2006, Santa Fe Pacific Gold and Newmont produced 4.2 Moz of gold at an average grade of 2.06 g/t at Lone Tree, primarily from the N-S– to NNW-SSE–striking Wayne zone. The ore is located between the Roberts Mountain and Golconda thrusts in siliciclastic rocks of the Ordovician Valmy Formation and in the Pennsylvanian-Permian Battle Mountain and Edna Mountain Formations, and above the Golconda thrust in siliciclastic and carbonate rocks of the Mississippian to Permian Havallah sequence. Ore is also hosted by rhyolitic dikes that were emplaced at 40.95 ± 0.06 Ma based on zircon U-Pb chemical abrasion-thermal ionization mass spectrometry. The gold is associated with sericitic and argillic alteration of the siliciclastic rocks and dikes and with decarbonatization and Fe carbonate alteration of the carbonate-bearing units, as well as in Fe-As sulfide and finegrained quartz alteration of all rock types. Oxidation affects 30 to 45% of the deposit, penetrating into the stratigraphy along numerous steeply dipping north-south, east-west, and north-northeast–south-southwest structures. Gold is positively correlated with Ag, As, Hg, and Sb. The highest Au grades occur in quartz-sulfide ore hosted in siliciclastic and carbonate sedimentary rocks and rhyolitic intrusions. In this ore style, fine-grained quartz and sericite are intergrown with disseminated sulfide minerals (quartz-sericite-pyrite alteration), constituting cores of weakly mineralized pyrite or marcasite, which are surrounded by fuzzy arsenopyrite rims that contain up to ~2,000 ppm Au. Low gold grades occur in late-stage banded pyrite breccias consisting of a finely zoned Au-poor pyrite matrix surrounding jigsaw-fit clasts of quartz-, illite-, barite-, and adularia-altered siliciclastic rock. The timing of main-stage mineralization is bracketed between the emplacement of the dikes and an adularia 40 Ar/ 39 Ar age of 40.14 ± 0.74 Ma. Sericite intergrown with arsenopyrite-rimmed pyrite in phenocrysts of the rhyolite dikes gave δ 18 O values of 1.6 to 9.5‰ and δ D values of –105 to –145‰. For temperatures of 300 ± 100°C, the calculated fluid isotopic compositions are consistent with felsic magmatic water and minor modifications by mixing with meteoric water and exchange with wall rocks. In the silica-sulfide ore, in situ isotopic laser ablation-multicollector-inductively coupled plasma-mass spectrometry (LA-MC-ICP-MS) analyses of pyrite cores yielded δ 34 S values ranging from 3.4 to 7.7‰, with average values of 5.6‰ in the felsic dikes, 4.5‰ in the siliciclastic rocks, and 5.3‰ in the carbonate rocks. These values match conventional pyrite δ 34 S data reported for Eocene porphyry systems elsewhere in the district. Nanoscale secondary ion mass spectrometry analyses show that gold and associated trace elements occur in submicron-scale zones within arsenopyrite rims on pyrite. The average δ 34 S values of the arsenopyrite rims are 5.3 to 6.5‰ heavier than the pyrite cores, indicating cooling and an increasing H 2 S/SO 2 ratio. The highest grades resulted from episodic pulses of a gold-rich fluid that was partly derived from, or exchanged with, the sedimentary host rocks. In situ LA-MC-ICP-MS δ 34 S values for the late-stage banded pyrite breccia become progressively lighter from veinlet margin to center, reaching a low of –32‰. These veinlets indicate a shift from main-stage quartz-sericite-pyrite and intermediate argillic alteration to more neutral pH and oxidizing conditions during late-stage mineralization, indicating either increasing interaction between the fluid and sedimentary sulfur sources in the host-rock package or bacterial sulfate reduction and supergene sulfide precipitation.

Nevada↗
USGS2020

Noble gases fingerprint the source and evolution of ore-forming fluids of Carlin-type gold deposits in the Golden Triangle, south China

Precise constraints on the source and evolution of ore-forming fluids of Carlin-type gold deposits in the Golden Triangle (south China) are of critical importance for a better understanding of the ore genesis and a refined genetic model for gold mineralization. However, constraints on the source of ore fluid components have long been a challenge due to the very fine grained nature of the ore and gangue minerals in the deposits. Here we present He, Ne, and Ar isotope data of fluid inclusion extracts from a variety of ore and gangue minerals (arsenian pyrite, realgar, quartz, calcite, and fluorite) representing the main and late ore stages of three well-characterized major gold deposits (Shuiyindong, Nibao, and Yata) to provide significant new insights into the source and evolution of ore-forming fluids of this important gold province. Measured He isotopes have R/R A ratios ranging from 0.01 to 0.4 that suggest a maximum of 5% mantle helium with an R/R A of 8. The Ne and Ar isotope compositions are broadly comparable to air-saturated water, with a few analyses indicating the presence of an external fluid containing nucleogenic 38 Ar and radiogenic 40 Ar. Plotted on the 20 Ne/ 4 He vs. helium R/R A and 3 He/ 20 Ne vs. 4 He/ 20 Ne diagrams, the results define two distinct arrays that emanate from a common sedimentary pore fluid or deeply sourced metamorphic fluid end-member containing crustal He. The main ore-stage fluids are interpreted as a mixture of magmatic fluid containing mantle He and sedimentary pore fluid or deeply sourced metamorphic fluid with predominantly crustal He, whereas the late ore-stage fluids are a mixture of sedimentary pore fluid or deeply sourced metamorphic fluid bearing crustal He and shallow meteoric groundwater containing atmospheric He. Results presented here, when combined with independent evidence, support a magmatic origin for the ore-forming fluids. The ascending magmatic fluid mixed with sedimentary pore fluid or deeply sourced metamorphic fluid in the ore stage and subsequently mixed with the meteoric groundwater in the late ore stage, eventually producing the Carlin-type gold deposits in the Golden Triangle.

Golden Triangle, south China↗
USGS2012

Quantification of water-level variability effect on plant species populations using paleoecological and hydrological time series data

Soil cores provide valuable data on historical changes in vegetation and hydrologic conditions. Empirical models were developed to quantify the effect of meteorological and hydrologic forcing on plant species distributions over a 110-year period in Water Conservation Area 1 (WCA1) in the Florida Everglades, also known as the Arthur R. Marshall Loxahatchee National Wildlife Refuge. Empirical models that predict plant species distributions at sites within WCA1 were developed by linking temporally sparse seed bank data from soil cores with continuous multi-decadal daily meteorological and hydrologic time series data. The meteorological data included rainfall and maximum daily temperatures that spanned the entire study period of 110 years. The hydrologic data included stage data from two gages in WCA1 established in 1954. These stage data were hindcasted to be concurrent with the meteorological data by using correlation models that fit measured stages as a function of the meteorological parameters. The historical plant species data came from seven peat cores from WCA1. Different depths from each core were carbon-dated and assayed for relative percentages of 83 plant species using pollen counts. The oldest dates were more than 1,000 years old; however, only core data that overlapped the study period were used, for a total of 67 assays among the seven cores. Twenty-three of the species had ratios of at least 5 percent for one or more of the 67 assays, hereafter referred to as the "top23". Using the assays as input vectors, the top23 were grouped using the k-means clustering into four plant classes that represented the extent to which the various species have historically appeared together. This reduced the modeling problem to one of predicting the relative ratios of the four plant classes from the hindcasted stage time-series data. A separate empirical model was developed for each class using a multi-layer perceptron artificial neural network, which provides multivariate, nonlinear curve fitting. The models predicted the relative ratios of the classes, and the sums of the predictions are near 1. The coefficient of determination (R2) of the models varied from 0.87 to 0.96, indicating that the relative ratios of the plant classes are predictable, and therefore controllable, from stage forcing. Similar soil cores are available for the Coastal Plain of North Carolina and are planned for the Congaree National Park in South Carolina.

Florida↗
USGS2016

River rating complexity

Accuracy of streamflow data depends on the veracity of the rating model used to derive a continuous time series of discharge from the surrogate variables that can readily be collected autonomously at a streamgage. Ratings are typically represented as a simple monotonic increasing function (simple rating), meaning the discharge is a function of stage alone, however this is never truly the case unless the flow is completely uniform at all stages and in transitions from one stage to the next. For example, at some streamflow-monitoring sites the discharge on the rising limb of the hydrograph is discernably larger than the discharge at the same stage on the falling limb of the hydrograph. This is the so-called “loop rating curve” (loop rating). In many cases, these loops are quite small and variation between rising- and falling-limb discharge measurements made at the same stage are well within the accuracy of the measurements. However, certain hydraulic conditions can produce a loop that is large enough to preclude use of a monotonic rating. A detailed data campaign for the Mississippi River at St. Louis, Missouri during a multi-peaked flood over a 56-day period in 2015 demonstrates the rating complexity at this location. The shifting-control method used to deal with complexity at this site matched all measurements within 8%.

Conference Paper↗