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Geology topics

J. C. Blodgett

Publications and source records attributed to J. C. Blodgett.

At least 19 recordsLinked to original sources
USGS1996

Storage capacity, detention time, and selected sediment deposition characteristics for Gull and Silver Lakes, Mono County, California

Bathymetric surveys made in September 1994 indicate the maximum storage capacity of Gull and Silver Lakes, California, is about 2,400 and 3,000 acre-feet, respectively. During March through October 1994, the lake level dropped 0.7 feet at both Gull Lake and Silver Lake. The associated change in storage was 60 acre-feet at Gull Lake and 80 acre-feet at Silver Lake. The flow detention time for average annual flow conditions at Gull Lake is about 2.5 years and for Silver Lake, the average detention time is about 19 days. Sediment deposition at the inlet to Silver Lake has been monitored since 1951 using aerial photography. During 1963 through 1994, the area of sediment deposition increased from 0.32 to about 2.4 acres. Analyses of these data indicate that the rate of deposition was lower during 1951-72 than the rate during 1973-94. Sediment deposition at the lake inlet is a continuing phenomenon.

Open-File Report↗
USGS1995

Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, April 1994 to March 1995

Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, were collected from April 1994 to March 1995. Water samples were analyzed for major ions and trace elements, nutrients, methylene blue active substances, and oil and grease. Field measurements were made for discharge, specific conductance, pH, water temperature, barometric pressure, dissolved oxygen, and alkalinity. Additional data collected include vertical water profiles of specific conductance, pH, water temperature, and dissolved oxygen collected at 3.3-foot intervals for Gull and Silver Lakes; chlorophyll-a and -b concentrations and Secchi depth for Gull and Silver Lakes; sediment interstitial- water nutrient concentrations in cores from Gull Lake; and lake surface and volume of Gull and Silver Lakes.

Open-File Report↗
USGS1995

Precipitation depth-duration and frequency characteristics for Antelope Valley, Mojave Desert, California

Methods to evaluate changes in the volume of storm runoff from drainage basins that are likely to be urbanized are needed by land-use planning agencies to establish criteria for the design of flood-control systems. To document the changes in runoff volume of basins that may be urbanized, nine small basins that are considered representative of varying hydrologic conditions in Antelope Valley, California, were selected for detailed study. Precipitation and stream-gaging stations were established and data were collected for the period 1990-93. The data collected at these U.S. Geological Survey stations were supplemented by data collected at 35 Long-term precipitation stations operated by the National Oceanic and Atmospheric Administration and the Los Angeles County Department of Public Works. These data will be used to calibrate and verify rainfall-runoff models for the nine basins. Results of the model runs will then be used as a guide for estimating basin runoff characteristics throughout Antelope Valley. Annual precipitation in Antelope Valley ranges from more than 20 inches in the mountains to less than 4 inches on the valley floor. Most precipitation in the valley falls during the months of December through March, but cyclonic storms in the fall and convectional storms in the summer sometimes occur. The duration of most storms ranges from 1 to 8 days, but most of the precipitation usually occurs within the first 2 days. Many parts of the valley have been affected by storms with precipitation depths that equal or exceed 0.60 inch per hour. The storms of January 1943 and March 1983 were the most intense storms of record, with recurrence intervals greater than 100 years in some parts of the valley. Depth-duration ratios were calculated by disaggregating daily total precipitation data for intervals of 1, 2, 3, 4, 6, 12, and 18 hours for storms that occurred during 1990-93. The hourly total precipitation data were then disaggregated at 5-minute intervals. A comparison of the depth-duration data collected during 1990-93 at the Geological Survey stations with the data collected at the other stations indicated that the 1990-93 data are not representative of historical storms. Therefore, depth-duration ratios developed using these data should be considered preliminary for use in disaggregating the historical hourly data for Antelope Valley. Annual maximum 24-hour precipitation records were used to calculate precipitation depth-frequency relations for 23 stations in the valley using the log Pearson type III distribution. These calculations indicate that the storms of January 1943 and March 1983 were the most intense of record in the valley with recurrence intervals greater than 100 years.

Water-Resources Investigations Report↗
USGS1993

Measurement of bridge scour at the SR-32 crossing of the Sacramento River at Hamilton City, California, 1987-92

A study of the State Route 32 crossing of the Sacramento River near Hamilton City, California, is being made to determine those channel and bridge factors that contribute to scour at the site. Three types of scour data have been measured-channel bed (natural) scour, constriction (general) scour, and local (bridge-pier induced) scour. During the years 1979-93, a maximum of 3.4 ft of channel bed scour, with a mean of 1.4 ft, has been measured. Constriction scour, which may include channel bed scour, has been measured at the site nine times during the years 1987-92. The calculated amount of constriction scour ranged from 0.2 to 3.0 ft, assuming the reference is the mean bed elevation. Local scour was measured four times at the site in 1991 and 1992 and ranged from -2.1 (fill) to 11.6 ft , with the calculated amounts dependent on the bed reference elevation and method of computation used. Surveys of the channel bed near the bridge piers indicate the horizontal location of lowest bed elevation (maximum depth of scour) may vary at least 17 ft between different surveys at the same pier and most frequently is located downstream from the upstream face of the pier.

Conference Paper↗
USGS1989

Flood of January 1982 in the San Francisco Bay area, California

A major winter storm originating over the Pacific Ocean moved through central California in early January 1982. As much as 16 inches of rain fell in Marin County and 25 inches in the mountains bordering Santa Cruz County. The storm of January 3-5, 1982 had a stable atmospheric structure, and the layer of moist maritime air was confined to altitudes between 50 and 700 ft; this phenomenon caused the rain to fall most heavily along the lower slopes of the coastal mountains. As a result of antecedent rainfall, streamflow in the San Francisco Bay area exceeded normal from the end of October to the end of December 1981. For most streams, the January 1982 flood was the largest since the flood of December 1955, but it was not significantly large in comparison with historic peak-flow data. Damages associated with the storm were substantial, but flooding from stream runoff was not the major problem. Greater than normal antecedent rainfall, together with the prolonged heavy rain, liquified the supersaturated soil cover and caused numerous slope failures and debris flows on steep, unstable slopes. The median recurrence interval of the 1982 peak for 66 streamflow-gaging stations in the San Francisco Bay area is 10 years; for the 1955 flood, the median recurrence interval for 16 stations is 11 years. Streams with highest unit peak runoff were in the Santa Cruz Mountains and North Bay subareas. Median recurrence intervals of flood volumes for durations of 1, 3, and 8 consecutive days during the January 1982 flood are 18, 11, and 8; these recurrence intervals are comparable to those of the December 1955 flood, which are 13 , 16, and 14 years. (USGS)

Water-Resources Investigations Report↗
USGS1988

Determination of bench-mark elevations at Bethel Island and vicinity, Contra Costa and San Joaquin counties, California, 1987

Elevations of 49 bench marks in the southwestern part of the Sacramento-San Joaquin River Delta were determined during October and November 1987. A total of 58 miles of level lines were run in the vicinity of Bethel Island and the community of Discovery Bay. The datum of these surveys is based on a National Geodetic Survey bench mark T934 situated on bedrock 10.5 mi east of Mount Diablo and near Marsh Creek Reservoir. The accuracy of these levels, based on National Geodetic Survey standards, was of first, second, and third order, depending on the various segments surveyed. Several bench marks were noted as possibly being stable, but most show evidence of instability. (USGS)

Open-File Report↗
USGS1988

Profile of Sacramento River, Freeport to Verona, California, flood of February 1986

A major storm in February 1986 caused record flooding in the Sacramento River and other nearby basins in north-coastal and central California. As part of an effort to document this flood, the peak water surface profile of a 33 mi reach of the Sacramento River was surveyed between Freeport and Verona, California. Supplementary profiles in this reach include elevations of the approximate top of levee, flood plain, and the water surface on March 17, 1987. On the Sacramento River at Sacramento, the peak discharge of 117,000 cu ft/sec occurred February 19 and 20, 1986. The peak stage of 30.58 ft on February 19 is the highest on record, including the period prior to construction of large flood control dams in the Sacramento River basin beginning with Shasta Dam in 1942. The February 1986 flood profile of the Sacramento River between the mouth of the American River and the Sacramento Weir (located upstream from the American River) shows a reverse water surface slope with a corresponding drop of about 0.13 ft. On the Sacramento River at Verona, upstream from Sacramento, a peak stage of 39.11 ft occurred February 20 (peak discharge 92,900 cu ft/sec) due to runoff from upstream tributaries. The February 1986 peak stage is the highest of record for 1914-87 (no record for 1918-20, 1922-25). The previous peak stage of record at Verona, March 1, 1940, was 38.20 ft, with a discharge of 79,200 cu ft/sec.

California↗
USGS1988

Channel morphology of Cottonwood Creek near Cottonwood, California, from 1940 to 1985

Proposed construction of two dams on Cottonwood Creek California , has caused concern that resulting streamflow modification may alter downstream channel morphology. Baseline information on Cottonwood Creek channel characteristics from 1982-83 field surveys and 1940-84 aerial photographs indicates an alluvial channel that consists of a braided inner main channel within a broader flood channel, with no clear topographic break between the main and flood channels. The braided channel is subject to large and rapid position shifts in the flood channel, which meanders within the valley fill; however, the position of the flood channel has remained relatively stable since 1940. Mean slope of Cottonwood Creek is 0.0017 and that of South Fork Cottonwood Creek is 0.0020. Fluctuations of mean bed elevation appear to be random with no apparent long-term trend of aggradation or degradation. Mean bed-material size ranged from 3 to 82 millimeters. Low-flow channel sinuosity ranged from 1.04 to 1.47 from 1940 to 1984. Cumulative lateral migration for Cottonwood Creek decreased upstream, while for South Fork, it remained relatively constant. Net lateral migration was toward the right bank on Cottonwood Creek whereas no trend in net lateral migration is apparent for the South Fork. (USGS)

Water-Resources Investigations Report↗
USGS1986

Rock riprap design for protection of stream channels near highway structures; Volume 1, Hydraulic characteristics of open channels

Volume I discusses the hydraulic and channel properties of streams, based on data from several hundred sites. Streamflow and geomorphic data have been collected and developed to indicate the range in hydraulic factors typical of open channels , to assist design, maintenance, and construction engineers in preparing rock riprap bank protection. Typical channels were found to have maximum-to-mean depth ratio of 1.55 and a ratio of hydraulic radius to mean depth of 0.98, which is independent of width. Most stable channel characteristics for a given discharge are slope, maximum depth, and hydraulic radius. (See also W89-04911) (Author 's abstract)

Water-Resources Investigations Report↗
USGS1984

Estimation of streamflow for selected sites on the Carson and Truckee rivers in California and Nevada, 1944-80

Daily mean and monthly discharges were estimated for 10 sites on the Carson and Truckee Rivers for periods of incomplete records and for tributary sites affected by reservoir regulation. On the basis of the hydrologic characteristics, stream-flow data for a water year were grouped by month or season for subsequent regression analysis. In most cases, simple linear regressions adequately defined a relation of streamflow between gaging stations, but in some instances a nonlinear relation for several months of the water year was derived. Statistical data are presented to indicate the reliability of the estimated streamflow data. Records of discharges including historical and estimated data for the gaging stations for the water years 1944-80 are presented. (USGS)

Water-Resources Investigations Report↗
USGS1982

Floodflow characteristics of Honcut Creek at State Highway 70 bridges near Live Oak, California

State Highway 70 crosses Honcut Creek near Live Oak about 3 miles upstream from its confluence with the Feather River by a series of three bridges separated by short approach embankments. The California Department of Transportation is planning to replace or widen the three bridges. This report evaluates flow characteristics of the existing and proposed crossings. The distribution of flow across the floodplain and water-surface elevation of Honcut Creek at the site are affected by levees, a natural channel constriction, agricultural improvements on the floodplain, and high water levels on the Feather River. The average recurrence interval for overbank flow is less than 2 years, and for flows equal to the flood of January 12, 1980 (discharge, 10,100 cubic feet per second), is about 2. 5 years. A flood with an average recurrence interval of 50 years would discharge about 19,000 cubic feet per second. Flooding caused by high stages on the Feather River has occurred seven times during the period 1964-80. For flows exceeding 20,000 cubic feet per second on Honcut Creek, and assuming present bridge conditions, backwater at the approach section about 400 feet upstream from the bridge is about 0.4 foot. If bridge l (left bank bridge) is eliminated, backwater conditions at the approach section would increase to 0.5 foot. Backwater effects extend upstream more than 3,000 feet when flows exceed about 5,000 cubic feet per second. The present arrangement of the bridges and approach embankments occupies about 66 percent of the channel (between the levee and high ground). Measurements of the average velocity of flow at a bridge range from l to 3.2 feet per second, depending on the flood stages of the Feather River. The maximum point velocity of flow measured during the 1979-80 flood season was 5. 6 feet per second. In general, flow velocities will be less than about 6 feet per second because flooding and high stages on the Feather River create ponded conditions at the bridge site. For present channel and bridge conditions, overbank flows are distributed among the three bridges in a proportion of about 10, 40, and 50 percent for flows from 2,850 to 8,480 cubic feet per second.

California↗
USGS1981

Floodflow characteristics of the Sacramento River in the vicinity of Gianella Bridge, Hamilton City, California

Floodflow, channel, and geomorphic data were assembled to evaluate the characteristics of flooding of the Sacramento River at the Gianella Bridge on State Highway 32 at Hamilton City, Calif. The bridge, constructed with a large center pier and drawrest structure in 1908, constricts floodflows at the site. Variations in river sinuosity, slope, and alinement between 1946 and 1980, indicate that channel changes are significant during short (2- or 3-year) intervals of time. Over long periods, however, the channel appears to be in equilibrium. The flood plain extends several miles upstream and downstream from the site. Soils on the flood plain are sandy-silt loam, easily eroded by streamflow. Overflow to the flood plain is limited by levees along both banks that are overtopped or bypassed when floods exceed 130,000 cubic feet per second in the main channel. Backwater in the main channel upstream from the bridge is about 0.6 feet for flows exceeding 159,000 cubic feet per seconds, and extends more than 1.9 miles upstream, depending on the magnitude of flooding. The bridge structure occupies about 12 percent of the channel during all flows. The distribution of flow at the bridge is affected by piers for about 13 percent of the channel width. Highest velocities of flow are 13 feet per second. (USGS)

Open-File Report↗
USGS1980

Flood data for the Sacramento River and Butte Basin, 1878 to 1978, Sacramento Valley, California

Streamflow data at various locations were assembled for the Sacramento River between Red Bluff and Meridian, Calif., and for Butte Basin, which serves as an overflow basin during periods of flooding. Data were obtained from various Federal and State agencies and private sources to document the magnitude of flooding from 1875 to 1978. The assembled data include annual maximum flood stages and discharges for the period of record at gaging stations, and flood stages at numerous staff gages, crest-stage gages, and high-water mark sites throughout the study area. Tabulations of floodflow measurements made at or near gaging stations, including the cross-sectional area of the channel and velocities, are presented. Cross sections of the Sacramento River near Chico Landing surveyed in 1978 and earlier surveys to show the size of Butte Basin have been included. A detailed list of references is presented giving the sources of the data included in this report. Many of these sources present detailed descriptions of flooding at various sites. (USGS)

Open-File Report↗