SEARCH · Search USGS

Results for “Clear Waters”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

USGS2016

The South Carolina bridge-scour envelope curves

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations to evaluate historical, riverine bridge scour in the Piedmont and Coastal Plain regions of South Carolina. These investigations included data collected at 231 riverine bridges, which lead to the development of bridge-scour envelope curves for clear-water and live-bed components of scour. The application and limitations of the South Carolina bridge-scour envelope curves were documented in four reports, each report addressing selected components of bridge scour. The current investigation (2016) synthesizes the findings of these previous reports into a guidance manual providing an integrated procedure for applying the envelope curves. Additionally, the investigation provides limited verification for selected bridge-scour envelope curves by comparing them to field data collected outside of South Carolina from previously published sources. Although the bridge-scour envelope curves have limitations, they are useful supplementary tools for assessing the potential for scour at riverine bridges in South Carolina.

South Carolina↗

USGS1978

Sediment transport in the Feather River, Lake Oroville to Yuba City, California

Regulation of the Feather River by Oroville Dam and reservoir in northeast California (beginning in 1967) changed the streamflow and sediment discharge downstream from the dam. Changes in channel geometry to adjust to the new regimen were still in process in 1975. Streamflow and sediment concentration and discharge had decreased. Median streamflow at Feather River near Gridley and Feather River at Yuba City, 27 miles and 49 miles downstream from the dam, had not changed, although the frequency of flow rates less than median increased and the frequency of flow rates greater than median, and which transport most sediment, decreased. Sediment-transport data indicate an increase in sediment yield from the 1965-67 period to the 1968-75 period in the basin downstream from Gridley to Yuba City , although the quantity of sediment transported was reduced owing to removal of sediment by Oroville Dam and to reduced streamflow. The increase in yield, assuming no change in tributary inflow, may be attributed partly to channel erosion accelerated by the clear-water releases and to the change in frequency and magnitude of flow rates.

California↗

USGS1994

Stream-aquifer interactions in the Straight River area, Becker and Hubbard counties, Minnesota

The Straight River, in north-central Minnesota, is a trout stream having cold, clear water. The 75-square-mile Straight River watershed contributes flow to the stream. The watershed is underlain by highly transmissive surficial and confined-drift aquifers. Ground-water discharge from these aquifers sustains flow in the Straight River, and the cold water supports a population of trout. Water withdrawals from these aquifers are increasing in response to changes in land use from dry-land to irrigated fanning. Degradation of the stream's habitat for trout could result from the following: a decrease in ground-water discharge to the stream caused by ground-water withdrawals for irrigation, an increase in ground-water temperature resulting from percolation of irrigated water to the ground-water system, and introduction of agricultural chemicals to the stream through ground-water flow or runoff. Physical data indicate a hydraulic connection between the stream and the surficial aquifer. Discharge of the Straight River increases from about 25 cubic feet per second at the outfall from a reservoir near the headwaters to about 51 cubic feet per second near the mouth. The rate of streamflow gain during summer decreases downstream, possibly as a result of ground-water withdrawal for irrigation. The water table and potentiometric surface of the uppermost confined-drift aquifer generally slope to the southeast and locally toward rivers and lakes; gradients decline to about 5 feet per mile from spring to summer. Daily fluctuations of stream temperature are as great as 15 degrees Celsius during the summer, primarily in response to changes in air temperature. Ground-water discharge to the Straight River decreases stream temperature during the summer. Results of simulations from a stream-temperature model indicate that daily changes in stream temperature are strongly influenced by solar radiation, wind speed, stream depth, and ground-water inflow. Results of simulations from ground-water-flow and stream-temperature models developed for the investigation indicate a significant decrease in ground-water flow could result from ground-water withdrawal at rates similar to those measured during 1988. This reduction in discharge to the stream could result in an increase in stream temperature of 0.5 to 1.5 degrees Celsius. Nitrate concentrations in shallow wells screened at the water table, in some areas, are locally greater than the limit set by the Minnesota Pollution Control Agency. Nitrate concentrations in water from deeper wells and in the stream are low, generally less than 1.0 milligram per liter.

Minnesota↗

USGS2017

ASTER measurement of supraglacial lakes in the Mount Everest region of the Himalaya

We demonstrate an application of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images to detect and monitor supraglacial lakes on glaciers in the Mount Everest region in Tibet (Xizang) and Nepal. ASTER offers powerful capabilities to monitor supraglacial lakes in terms of (1) surface area, growth and disappearance (spatial resolution = 15 m), (2) turbidity (15 m resolution), and (3) temperature (90 m resolution). Preliminary results show an overall similarity of supraglacial lakes on three glaciers. Lakes have widely varying turbidity as indicated by color in visible/near-infrared bands 1-3, the largest lakes being bright blue (highly turbid), cold (near 0??C) and hydrautically connected with other lakes and supraglacial streams, while small lakes are mostly dark blue (relatively clear water), warmer (>4??C), and appear hydrautically isolated. High levels of turbidity in supraglacial lakes indicate high rates of meltwater input from streams or erosion of ice cliffs, and thus are an indirect measure relating to the activity and hydraulic integration of the lake with respect to other lakes and streams in the glacier.

Annals of Glaciology↗

USGS2023

White perch health relative to urbanization and habitat degradation in Chesapeake Bay tributaries. II. Hepatic and splenic macrophage aggregates

Macrophage aggregate (MA) abundance in fish is a useful general biomarker of contaminant exposures and environmental stress. Hepatic and splenic MAs were evaluated in semi-anadromous white perch Morone americana (Gmelin, 1789) from the urbanized Severn River (S) and the more rural Choptank River (C), Chesapeake Bay. Fish were collected from different sites in the annual migratory circuit in each river that corresponded to active spawning in late winter-early spring, summer regenerating, autumn developing, and winter spawning-capable phases. An age-associated progressive increase in the total volume of MAs (MAV) was evident in the liver and spleen. Mean hepatic MAV (range in seasonal means, C: 6.4-23.1 mm 3 ; S: 15.7-48.7 mm 3 ) and mean splenic MAV (C: 7.3-12.6 mm 3 ; S: 16.0-33.0 mm 3 ) differed significantly among seasons and were significantly greater in females and in Severn River fish. Age and river were the most influential factors, suggesting that increased MAV in Severn River fish resulted from chronic exposures to higher concentrations of environmental contaminants. Hepatic MAV was directly related to the relative volume of copper granules in the liver. Less influential factors on splenic MAV included fish condition, trematode infections, and granulomas, indicating possible functional differences in MAs by organ. While organ volumes were strongly linked to gonadosomatic index (GSI) and reproductive phase, the reason for seasonal differences in MAV was less clear. Water temperature, salinity, and dissolved oxygen were not significantly related to MAV, and indicators of reproductive phase (hepatosomatic index and GSI) were significant but less important in explaining variation in MAV.

Chesapeake Bay watershed↗

USGS2016

Effects of turbidity on predation vulnerability of juvenile humpback chub to rainbow and brown trout

Predation on juvenile native fish by introduced rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta is considered a significant threat to the persistence of endangered humpback chub Gila cypha in the Colorado River in Grand Canyon. Diet studies of rainbow and brown trout in Glen and Grand canyons indicate that these species eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable depending on the physical conditions under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile humpback chub changes in response to changes in turbidity. In overnight laboratory trials, we exposed hatchery-reared juvenile humpback chub and bonytail Gila elegans (a surrogate for humpback chub) to adult rainbow and brown trout at turbidities ranging from 0 to 1,000 formazin nephlometric units. We found that turbidity as low as 25 formazin nephlometric units significantly reduced predation vulnerability of bonytail to rainbow trout and led to a 36% mean increase in survival (24–60%, 95% CI) compared to trials conducted in clear water. Predation vulnerability of bonytail to brown trout at 25 formazin nephlometric units also decreased with increasing turbidity and resulted in a 25% increase in survival on average (17–32%, 95% CI). Understanding the effects of predation by trout on endangered humpback chub is important when evaluating management options aimed at preservation of native fishes in Grand Canyon National Park. This research suggests that relatively small changes in turbidity may be sufficient to alter predation dynamics of trout on humpback chub in the mainstem Colorado River and that turbidity manipulation may warrant further investigation as a fisheries management tool.

Journal of Fish and Wildlife Management↗

USGS2003

The effects of ultraviolet-B radiation on freshwater invertebrates: Experiments with a solar simulator

There is concern that decreases in stratospheric ozone will lead to hazardous levels of ultraviolet-B (UV-B) radiation at the Earth's surface. In clear water, UV-B may penetrate to significant depths. The purpose of the current study was to compare the sensitivity of freshwater invertebrates to UV-B. We used a solar simulator, calibrated to match local ambient solar radiation, to expose five species of freshwater invertebrates to enhanced levels of UV-B radiation. UV-B measurements in a eutrophic pond revealed that 10% of the irradiance penetrated to 30-cm depth and 1% to 57-cm depth. The irradiance at the upper 5-20 cm was comparable to levels used in the simulator. Median lethal dose (LD50) values were determined for the cladocerans Ceriodaphnia reticulata, Scapholeberis kingii (two induced color morphs), and Daphnia magna; the ostracod Cyprinotus incongruens; and the amphipod Hyalella azteca. Among the species, 96-h LD50 estimates were quite variable, ranging from 4.2 to 84.0 ??W cm-2. These estimates indicated S. kingii to be highly sensitive and H. azteca, C. reticulata, and D. magna to be moderately sensitive, whereas the ostracod C. incongruens was very tolerant to UV-B radiation. Overall, this study suggests that, in shallow ponds without physical refuges, UV-B radiation would have the strongest effects upon cladocerans and amphipods occurring in the water column, whereas ostracods would be better protected.

Limnology and Oceanography↗

USGS1962

A photoelectric amplifier as a dye detector

A dye detector, based on a modified photoelectric amplifier, has been planned, built, and tested. It was designed to record automatically the time of arrival of fluorescein dye at predetermined points in a stream system. Laboratory tests and stream trials proved the instrument to be efficient. Small changes in color can be detected in turbid or clear water. The unit has been used successfully for timing intervals of more than 17 hours; significant savings of time and manpower have resulted. Replacement of the clock, included in the original device, with a recording milliammeter increases the efficiency of the unit by contin,!ously recording changes in turbidity. The addition of this component would increase the cost from $75 to approximately $105.

Technical Report↗

USGS1986

VISCOPLASTIC FLUID MODEL FOR DEBRIS FLOW ROUTING.

This paper describes how a generalized viscoplastic fluid model, which was developed based on non-Newtonian fluid mechanics, can be successfully applied to routing a debris flow down a channel. The one-dimensional dynamic equations developed for unsteady clear-water flow can be used for debris flow routing if the flow parameters, such as the momentum (or energy) correction factor and the resistance coefficient, can be accurately evaluated. The writer's generalized viscoplastic fluid model can be used to express such flow parameters in terms of the rheological parameters for debris flow in wide channels. A preliminary analysis of the theoretical solutions reveals the importance of the flow behavior index and the so-called modified Froude number for uniformly progressive flow in snout profile modeling.

Conference Paper↗

USGS1989

Local scour at bridge abutments

Comparison of local scour depths at bridge abutments computed using different equations yields a large variation in predicted values. To consolidate the fragmented results of previous investigations and assemble the most comprehensive data set possible, reported laboratory measurements of local scour at the end of an obstruction protruding from the side of an open channel of rectangular cross section were compiled from several sources. Regression analysis of these data was used to develop an equation that predicts maximum relative depth of local scour at bridge abutments for both clear-water and live-bed scour conditions.

Conference Paper↗

USGS1994

Effects of flow duration on local scour at bridge piers in New York

The relation of local scour to the duration of high flows and other hydraulic properties is being studied at 31 bridge sites in New York State. Clear-water scour is common at most of the sites, and local-scour holes that formed during prolonged high flows did not refill during flow recessions. The deepening of about 20 local-scour holes by subsequent high flows indicates that the length of time a flow exceeds a given discharge can affect local scour at a site. Many high flows of short duration did not cause scour. Hourly discharge data collected at nearby U.S. Geological Survey streamflow-gaging stations were used to develop a hydrograph-based factor that incorporates the duration and magnitude of high flows and the shape of the hydrograph (runoff rate per hour). This factor improved statistically derived estimates of local-scour depth. Combining the hydrograph-based factor with a momentum factor that represents flow velocity, water depth, and bed-material size decreased the standard error of estimate from 60 to 55 percent and increased the coefficient of determination from 0.66 to 0.73. The streambed of the Cohocton River at State Route 333 in Steuben County was lowered 40-60 cm near a pier during a high flow that exceeded the mean-annual peak discharge (Q2) for 71 hours March 31-April 3, 1993. A similar high flow at this site March 30-31, 1993 exceeded the Q2 for 21 hours but produced no scour. The streambed of the Otselic River at State Route 333 in Cortland County was lowered 170 cm near the pier during a high flow that exceeded the Q2 for 27 hours April 10-11, 1993; 30 cm of this scour occurred during the flow recession.

Conference Paper↗

USGS1993

Estimating bridge scour in New York from historical U.S. geological survey streamflow measurements

Historical streamflow measurements by the U.S. Geological Survey an bridge-inspection reports by the New York State Department of Transportation are being used to estimate scour at 31 bridges in New York State. Streamflow measurements that were made before, during, or after high flows are used to estimate scour and to define hydraulic properties associated with floods. Clear-water scour is common at most sites; local scour holes that formed during high flows did not refill after subsequent high flows. The 31 streambeds are armored by gravel; median particle size ranges form 22 to 68 millimeters. Streambed elevations measured after a high flow are assumed to represent the elevations during peak flow. Measurements at several bridges indicate scour by multiple high flows, severe floods, and debris. Three high flows at State Route 23 over the Otselic River in Cortland County produced 6.1 feet of local scour and partly exposed concrete pilings below the footing. Although the recurrence interval of each flow was less than 10 years, a 30-degree angle between the flow and the pier increased the tendency of the streambed to scour. State Route 427 over the Chemung River in Chemung County survived the 1972 flood ( recurrence interval greater than 100 years) because pilings supported the undermined piers. The maximum local scour during the 1972 flood was estimated to be 5.4 feet. A local-scour hole, 2.4 feet deep before the flood, was deepened to 7.8 feet.

Conference Paper↗

USGS1997

Resistance formulas in hydraulics-based models for routing debris flows

The one-dimensional, cross-section-averaged flow equations formulated for routing debris flows down a narrow valley are identical to those for clear-water flow, except for the differences in the values of the flow parameters, such as the momentum (or energy) correction factor, resistance coefficient, and friction slope. Though these flow parameters for debris flow in channels with cross-sections of arbitrary geometric shape can only be determined empirically, the theoretical values of such parameters for debris flow in wide channels exist. This paper aims to derive the theoretical resistance coefficient and friction slope for debris flow in wide channels using a rheological model for highly-concentrated, rapidly-sheared granular flows, such as the generalized viscoplastic fluid (GVF) model. Formulating such resistance coefficient or friction slope is equivalent to developing a generally applicable resistance formula for routing debris flows. Inclusion of a nonuniform term in the expression of the resistance formula proves useful in removing the customary assumption that the spatially varied resistance at any section is equal to what would take place with the same rate of flow passing the same section under conditions of uniformity. This in effect implies an improvement in the accuracy of unsteady debris-flow computation.

Conference Paper↗

USGS1985

Landsat-faciliated vegetation classification of the Kenai National Wildlife Refuge and adjacent areas, Alaska

A Landsat-based vegetation map was prepared for Kenai National Wildlife Refuge and adjacent lands, 2 million and 2.5 million acres respectively. The refuge lies within the middle boreal sub zone of south central Alaska. Seven major classes and sixteen subclasses were recognized: forest (closed needleleaf, needleleaf woodland, mixed); deciduous scrub (lowland and montane, subalpine); dwarf scrub (dwarf shrub tundra, lichen tundra, dwarf shrub and lichen tundra, dwarf shrub peatland, string bog/wetlands); herbaceous (graminoid meadows and marshes); scarcely vegetated areas ; water (clear, moderately turbid, highly turbid); and glaciers. The methodology employed a cluster-block technique. Sample areas were described based on a combination of helicopter-ground survey, aerial photo interpretation, and digital Landsat data. Major steps in the Landsat analysis involved: preprocessing (geometric connection), spectral class labeling of sample areas, derivation of statistical parameters for spectral classes, preliminary classification of the entree study area using a maximum-likelihood algorithm, and final classification through ancillary information such as digital elevation data. The vegetation map (scale 1:250,000) was a pioneering effort since there were no intermediate-sclae maps of the area. Representative of distinctive regional patterns, the map was suitable for use in comprehensive conservation planning and wildlife management.

Alaska↗

USGS2014

A guidance manual for assessing scour potential using the South Carolina bridge-scour envelope curves

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations of bridge scour in order to better understand regional trends of scour within South Carolina. The studies collected historic-scour data at approximately 200 riverine bridges including measurements of clear-water abutment, contraction, and pier scour, as well as live-bed contraction and pier scour. These investigations provided valuable insights for regional scour trends and yielded bridge-scour envelope curves for assessing scour potential associated with all components of scour at riverine bridges in South Carolina. The application and limitations of these envelop cureves were documents in three reports, Each repoort addresses different components of bridge scour and this, there is a need to develop an integrated procedure for applying the South Carolina bridge-scour envelope curves. To address this need, the U.S. Geological Survey and the South Carolina Department of Transportation initiated a cooperative effort to develop an integrated procedure and document the method in a guidance manual. In addition to developing the integrated procedure, field data from other investigations outside of South Carolina were used to verify the South Carolina bridge-source envelope curves.

South Carolina↗

USGS1994

Sediment balance and flushing flow analysis: Trinity River case study

The use of sediment yield as one aspect of a flushing flow analysis is explored in a case study of the Trinity River in northwestern California. Understanding sediment balance can help in the development of a flushing flow need, but hydraulic analysis must also be done. The most important flushing flow need for the Trinity River is to increase the Trinity River flows when flows in Grass Valley Creek and other tributaries draining the Shasta Bally Batholith are high. The goal is preventing deposition of sand and fines. These flows should be followed by clear-water flushing (i.e., flushing flows when the tributaries are not high) to remove fines and sand from the stream bed.

Book↗

USGS1986

Vegetation mapping of Nowitna National Wildlife Refuge, Alaska using Landsat MSS digital data

A Landsat-derived vegetation map was prepared for Nowitna National Wildlife Refuge. The refuge lies within the middle boreal subzone of north central Alaska. Seven major vegetation classes and sixteen subclasses were recognized: forest (closed needleleaf, open needleleaf, needleleaf woodland, mixed, and broadleaf); broadleaf scrub (lowland, alluvial, subalpine); dwarf scrub (prostrate dwarf shrub tundra, dwarf shrub-graminoid tussock peatland); herbaceous (graminoid bog, marsh and meadow); scarcely vegetated areas (scarcely vegetated scree and floodplain); water (clear, turbid); and other areas (mountain shadow). The methodology employed a cluster-block technique. Sample areas were described based on a combination of helicopter-ground survey, aerial photointerpretation, and digital Landsat data. Major steps in the Landsat analysis involved preprocessing (geometric correction), derivation of statistical parameters for spectral classes, spectral class labeling of sample areas, preliminary classification of the entire study area using a maximum-likelihood algorithm, and final classification utilizing ancillary information such as digital elevation data. The final product is a 1:250,000-scale vegetation map representative of distinctive regional patterns and suitable for use in comprehensive conservation planning.

Alaska↗

USGS1988

Intermediate-scale vegetation mapping of Innoko National Wildlife Refuge, Alaska using Landsat MSS digital data

A Landsat-derived vegetation map was prepared for lnnoko National Wildlife Refuge. The refuge lies within the northern boreal subzone of northwestern central Alaska. Six major vegetation classes and 21 subclasses were recognized: forest (closed needleleaf, open needleleaf, needleleaf woodland, mixed, and broadleaf); broadleaf scrub (lowland, upland burn regeneration, subalpine); dwarf scrub (prostrate dwarf shrub tundra, erect dwarf shrub heath, dwarf shrub-graminoid peatland, dwarf shrub-graminoid tussock peatland, dwarf shrub raised bog with scattered trees, dwarf shrub-graminoid marsh); herbaceous (graminoid bog, graminoid marsh, graminoid tussock-dwarf shrub peatland); scarcely vegetated areas (scarcely vegetated scree and floodplain); and water (clear, sedimented). The methodology employed a cluster-block technique. Sample areas were described based on a combination of helicopter-ground survey, aerial photo-interpretation, and digital Landsat data. Major steps in the Landsat analysis involved preprocessing (geometric correction), derivation of statistical parameters for spectral classes, spectral class labeling of sample areas, preliminary classification of the entire study area using a maximum-likelihood algorithm, and final classification utilizing ancillary information such as digital elevation data. The final product is 1:250,000-scale vegetation map representative of distinctive regional patterns and suitable for use in comprehensive conservation planning.

Alaska↗