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Paul Work, Ph.D., P.E., D.CE

Paul Work serves as the Program Chief for Estuarine Hydrodynamics and Sediment Transport at the USGS California Water Science Center in Sacramento, California.

Hydrodynamic Mixing in Keswick Reservoir

drifter with high-precision receiver to capture flow speeds

Keswick Reservoir, on California’s Sacramento River, receives contaminants from the Iron Mountain Mine Superfund site. California’s State Water Quality Control Board is supporting a USGS investigation of hydrodynamics and mixing in the reservoir via 3-D hydrodynamic modeling and field measurements. Drifters with dual-frequency GPS receivers record pathlines of the flow.

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Publications and Projects

Below are some recent publications and projects that Dr. Work has been involved with.

In his role at the California Water Science Center, Dr. Work oversees and conducts research on flows of water, sediment, and other water quality constituents in the San Francisco Estuary, including the Sacramento-San Joaquin River Delta system, and elsewhere. His team is responsible for, among other things, ensuring the integrity, timeliness and quality of surface water flow and quality data reported every fifteen minutes at more than fifty locations. This work is funded by the U.S. Army Corps of Engineers, the U.S. Bureau of Reclamation, the Departments of Water Resources and the State Water Quality Control Board in California, and other sponsors. The work is motivated by a desire to maintain and improve the environmental health of the bay-estuary system and its inhabitants, while simultaneously meeting human needs for water.

Professional Experience

  • Joined USGS in 2013

  • 20 years as a faculty member in civil and environmental engineering programs at Georgia Tech and Clemson University

  • Served as an engineering consultant on domestic and international port and harbor problems and development projects

Education and Certifications

  • Ph.D. in Coastal and Oceanographic Engineering from the University of Florida.

  • M.S. in civil engineering from the University of California - Berkeley

  • B.S. in civil engineering from the University of California - Berkeley

Affiliations and Memberships*

  • Tahoe Science Advisory Council

  • San Francisco Bay Conservation and Development Commission panel on sand mining

  • American Society of Civil Engineers (ASCE)

  • Academy of Coastal, Ocean, Port and Navigation Engineers (ACOPNE)

Science and Products

link
Side-looking acoustic Doppler velocity meter and water quality sonde

State of the Network: Long-Term, High-Frequency Flow and Water Quality Data in the San Francisco Estuary, California

The San Francisco Bay and Sacramento-San Joaquin Delta form one of the largest estuaries in the United States. Water flow and water quality in the San Francisco Bay-Delta Estuary are important to the economies of both California and the nation. The Bay-Delta system provides water to more than 25 million California residents and vast farmlands, as well as key habitat for birds, fish, and other...
By
California Water Science Center
link

State of the Network: Long-Term, High-Frequency Flow and Water Quality Data in the San Francisco Estuary, California

The San Francisco Bay and Sacramento-San Joaquin Delta form one of the largest estuaries in the United States. Water flow and water quality in the San Francisco Bay-Delta Estuary are important to the economies of both California and the nation. The Bay-Delta system provides water to more than 25 million California residents and vast farmlands, as well as key habitat for birds, fish, and other...
Learn More
link
USACE Drill Operator

Soil Stratigraphy and Erosion Potential on the American and Sacramento Rivers

Much of the Sacramento region is protected from flooding by levees constructed on the American and Sacramento Rivers, which join near downtown Sacramento before flowing to the Sacramento-San Joaquin River Delta.
By
California Water Science Center
link

Soil Stratigraphy and Erosion Potential on the American and Sacramento Rivers

Much of the Sacramento region is protected from flooding by levees constructed on the American and Sacramento Rivers, which join near downtown Sacramento before flowing to the Sacramento-San Joaquin River Delta.
Learn More
link
research boat on delta

Continuous Monitoring of Water Quality and Suspended-Sediment Transport in the San Francisco Bay and Delta

Our group at the USGS continuously monitors suspended-sediment concentration (SSC), turbidity, dissolved oxygen, temperature, salinity, and water level at many sites throughout the San Francisco Bay (Bay) and the Sacramento-San Joaquin Rivers Delta (Delta).Our work began in 1988 to explore the spatial and temporal variability of water quality and sediment transport and to provide decision makers...
By
California Water Science Center
link

Continuous Monitoring of Water Quality and Suspended-Sediment Transport in the San Francisco Bay and Delta

Our group at the USGS continuously monitors suspended-sediment concentration (SSC), turbidity, dissolved oxygen, temperature, salinity, and water level at many sites throughout the San Francisco Bay (Bay) and the Sacramento-San Joaquin Rivers Delta (Delta).Our work began in 1988 to explore the spatial and temporal variability of water quality and sediment transport and to provide decision makers...
Learn More
link
Invasive Aquatic Vegetation

Ecosystem Engineers: Impacts of Invasive Aquatic Vegetation on the Delta’s Critical Ecosystems

The Sacramento-San Joaquin Delta (Delta) is home to a diverse community of plants and animals and is the hub of California’s freshwater delivery system. The Delta supplies water for over 25 million Californians and supports millions of acres of farming, commercial and sport fishing, shipping and ports, and recreational boating.
By
California Water Science Center, Pacific Coastal and Marine Science Center
link

Ecosystem Engineers: Impacts of Invasive Aquatic Vegetation on the Delta’s Critical Ecosystems

The Sacramento-San Joaquin Delta (Delta) is home to a diverse community of plants and animals and is the hub of California’s freshwater delivery system. The Delta supplies water for over 25 million Californians and supports millions of acres of farming, commercial and sport fishing, shipping and ports, and recreational boating.
Learn More
link
Tule Perch

Understanding Influences on Habitat Quality for Delta Smelt and Other Imperiled Fish Populations

USGS scientists work to provide information needed to evaluate the efficacy of ongoing U.S. Burueau of Reclamation water management efforts in Bay-Delta.
By
California Water Science Center
link

Understanding Influences on Habitat Quality for Delta Smelt and Other Imperiled Fish Populations

USGS scientists work to provide information needed to evaluate the efficacy of ongoing U.S. Burueau of Reclamation water management efforts in Bay-Delta.
Learn More

Evaluation of Hydrodynamic Mixing in Keswick Reservoir, California, 2021-22

California's State Water Resources Control Board (SWRCB) wishes to quantify how water and constituents introduced via the outflow from the Spring Creek Diversion Dam mix with water within Keswick Reservoir. Of primary interest is the degree of dilution that exists when this introduced flow reaches the main stem of Keswick Reservoir, and how this mixing is influenced by different operational parame
By
California Water Science Center

Borehole Erosion Test data, Lower American and Sacramento Rivers, California, 2019 (ver. 3.0, July 2020)

Borehole erosion tests were performed to quantify sediment erosion rates as a function of depth below grade and flow speed at locations along the Sacramento and American Rivers in 2019. The dataset consists of: - borehole caliper files describing the initial geometry of the borehole, and its shape after each test flow event, - where available, a digital time series describing discharge into the ho
By
California Water Science Center

Sediment Concentration and Velocity Data to Assess Trapping by Submerged Vegetation

The acoustic Doppler current meter (ADCP) used in this study outputs binary data files containing measurement scheme, location, time, velocity, backscatter, boat heading, depth, and other parameters. These data are provided here in the manufacturer's "classic ASCII" format, as described in READMEforADCP.txt file associated with this data release. We also collected water samples for suspended-sedim
By
California Water Science Center

ADCP Data in Support of Water and Suspended-Sediment Flux Measurements at the Golden Gate, 2016-2017

Field observations of water and suspended-sediment fluxes at the Golden Gate were made over one ebb tide and one flood tide on three occasions: 1) 21-22 March 2016, following a large storm event that triggered the first flow into Yolo Bypass flood control structure since 2011; 2) 23 June of 2016, during a period of low freshwater inflow and 3) 27-28 February 2017, following several large storms of
By
California Water Science Center
Filter Total Items: 16

Seasonal and long-term clarity trend assessment of Lake Tahoe, California–Nevada

The clarity of Lake Tahoe, observed using a Secchi disk on a regular basis since the late 1960s, continues to be a sentinel metric of lake health. Water clarity is influenced by physical and biological processes and has declined in the five decades of monitoring, revealing differences between summer (June–September) and winter (December–March). This document summarizes key findings of a study of L
By
Water Resources, California Water Science Center, Nevada Water Science Center

American and Sacramento Rivers, California, erodibility measurements and model

Executive Summary  A previous report by the authors described sediment sampling and drilling by the U.S. Geological Survey (USGS) beside the American and Sacramento Rivers near Sacramento, California, in support of a U.S. Army Corps of Engineers project focused on regional flood control. The drilling was performed to define lithology, extract samples for laboratory testing, and perform borehole er
By
Water Resources, California Water Science Center

Trapping of suspended sediment by submerged aquatic vegetation in a tidal freshwater region: Field observations and long-term trends

Widespread invasion by non-native, submerged aquatic vegetation (SAV) may modify the sediment budget of an estuary, reducing the availability of inorganic sediment required by marshes to maintain their position in the tidal frame. The instantaneous trapping rate of suspended sediment in SAV patches in an estuary has not previously been quantified via field observations. In this study, flows of wat
By
Water Resources, California Water Science Center

Sediment lithology and borehole erosion testing, American and Sacramento Rivers, California

Executive SummaryA field investigation intended to measure the potential for erosion of sediments beside the American and Sacramento Rivers near Sacramento, California, is described. The study featured two primary components: (1) drilling and soil sampling to reveal lithology, down to depths matching the local river thalweg, where possible, and (2) borehole erosion tests (BETs) as described by Bri
By
Water Resources, California Water Science Center

State of the network: Long-term, high-frequency flow and water quality data in the San Francisco Estuary, California

The USGS California Water Science Center is heavily involved in the measurement of flow and water quality parameters in the San Francisco Estuary, with support from many partner agencies. The California Department of Water Resources (DWR), through the Interagency Ecological Program (IEP) is one of those agencies. This article describes the resulting efforts and methodologies and provides examples
By
Water Resources, California Water Science Center

Stratigraphic analysis of Corte Madera Creek flood control channel deposits

Sedimentation in a channel can reduce flood conveyance capability and potentially place nearby property and life at risk from flooding. In 1998, Marin County Public Works dredged the concrete-lined segment of Corte Madera Creek, which drains a hilly and largely urbanized watershed that terminates in San Francisco Bay, California. From then through 2015, approximately 4,100 cubic meters of sand and
By
Water Resources, California Water Science Center

Measurements of erosion potential using Gust chamber in Yolo Bypass near Sacramento, California

This report describes work performed to quantify the erodibility of surface soils in the Yolo Bypass (Bypass) near Sacramento, California, for use in the California Department of Water Resources (DWR) Yolo Bypass D-MCM mercury model. The Bypass, when not serving as a floodway, is heavily utilized for agriculture. During flood events, surface water flows over the soil, resulting in the application
By
Water Resources, California Water Science Center

Erosion characteristics and horizontal variability for small erosion depths in the Sacramento-San Joaquin River Delta, California, USA

Erodibility of cohesive sediment in the Sacramento-San Joaquin River Delta (Delta) was investigated with an erosion microcosm. Erosion depths in the Delta and in the microcosm were estimated to be about one floc diameter over a range of shear stresses and times comparable to half of a typical tidal cycle. Using the conventional assumption of horizontally homogeneous bed sediment, data from 27 of 3
By
Water Resources, California Water Science Center

Record-high specific conductance and water temperature in San Francisco Bay during water year 2015

The San Francisco estuary is commonly defined to include San Francisco Bay (bay) and the adjacent Sacramento–San Joaquin River Delta (delta). The U.S. Geological Survey (USGS) has operated a high-frequency (15-minute sampling interval) water-quality monitoring network in San Francisco Bay since the late 1980s (Buchanan and others, 2014). This network includes 19 stations at which sustained measure
By
Water Resources, California Water Science Center

Acoustic Doppler velocimeter backscatter for quantification of suspended sediment concentration in South San Francisco Bay, USA

A data set was acquired on a shallow mudflat in south San Francisco Bay that featured simultaneous, co-located optical and acoustic sensors for subsequent estimation of suspended sediment concentrations (SSC). The optical turbidity sensor output was converted to SSC via an empirical relation derived at a nearby site using bottle sample estimates of SSC. The acoustic data was obtained using an acou
By
Water Resources, California Water Science Center

Beach nourishment alternative assessment to constrain cross-shore and longshore sediment transport

A combined field and laboratory investigation was conducted to assess five options for creation of a recreational beach on a steep, armored shoreline on the eastern Black Sea coast. All designs incorporated a beach nourishment project placed between two existing, shore-normal, rubble-mound groins. Alternatives included the placement of a nearshore berm, longshore extensions added to the existing g
By
Water Resources, California Water Science Center

Innovation in monitoring: The U.S. Geological Survey Sacramento–San Joaquin River Delta, California, flow-station network

The U.S. Geological Survey (USGS) installed the first gage to measure the flow of water into California’s Sacramento–San Joaquin River Delta from the Sacramento River in the late 1800s. Today, a network of 35 hydro-acoustic meters measure flow throughout the delta. This region is a critical part of California’s freshwater supply and conveyance system. With the data provided by this flow-station ne
By
Water Resources, California Water Science Center

Non-USGS Publications**

Work, P.A., and Dean, R.G, 1995. Assessment and prediction of beach nourishment evolution. J. Waterway, Port, Coastal, and Ocean Eng., 121(3), American Soc. of Civil Eng. (ASCE), New York, NY, 182-189.
Dean, R.G., and Work, P.A., 1993. Interaction of navigational entrances with adjacent shorelines. J. Coastal Res., SI 18, 91-110.
Hansen, M.E., and Work, P.A., 1997. Short- and Long-term variability of ebb-tidal delta shoals: management implications. Eos, Transactions American Geophysical Union, 78(46), Nov. 18, 1997.
Work, P.A., and Kaihatu, J.M., 1997. Wave transformation at Pensacola Pass, FL: Field and numerical model results. J. Waterway, Port, Coastal, and Ocean Eng., 123(6), ASCE, New York, NY, 314-321.
Work, P.A., and Rogers, W.E., 1997. Wave transformation for beach nourishment projects. Coastal Eng., 32(1), Elsevier, Amsterdam, 1-18.
Work, P.A., Hansen, M., and Rogers, W.E., 1998. Bathymetric surveying with GPS technology and heave, pitch, and roll compensation, J. Surveying Eng., 124(2), ASCE, 73-90.
Work, P.A., and Rogers, W.E., 1998. Laboratory study of beach nourishment behavior. J. Waterway, Port, Coastal, and Ocean Eng., 124(5), ASCE, New York, NY, 229-237.
Atanov, G.A., Evseeva, E.G., and Work, P.A., 1998. The variational problem of water level stabilization in open channels. J. Hydraulic Eng., 124(1), ASCE, New York, NY, 50-54.
Work, P.A. Rogers, S.M., Jr., and Osborne, R., 1999. Retrofit superelevation of coastal residential structures. J. Water Resources Planning and Management, 125(2), ASCE, New York, NY, 88-93.
Kana, T.W., Hayter, E.J., and Work, P.A., 1999. Mesoscale sediment transport at Southeastern U.S. tidal inlets: conceptual model applicable to mixed energy settings. J. Coastal Res., 15(2), 303-313.
Work, P.A., Guan, J., Hayter, E.J., and Elçi, Ş., 2001. Mesoscale model for morphologic change at tidal inlets. J. of Waterway, Port, Coastal and Ocean Eng., 127(5), ASCE, 282-289.
Work, P.A., Moore, P., and Reible, D.D., 2002. Bioturbation, advection and diffusion of a conserved contaminant in a laboratory flume. AGU J. of Water Resources Res., 38(6), 24-1-24-9.
Work, P.A., Fehrenbacher, F., and Voulgaris, G., 2004. Nearshore impacts of dredging for beach nourishment. J. of Waterway, Port, Coastal and Ocean Eng., 130(6), ASCE, 303-311.
Demir, H., Otay, E., Work, P., and Borekçi, O., 2004. Shoreline change due to nearshore dredging. J. of Waterway, Port, Coastal and Ocean Eng., ASCE, 130(4), 170-178.
Gutierrez, B.T., Voulgaris, G., and Work, P.A., 2006. Cross-shore variation of wind-driven flows on the inner shelf in Long Bay, South Carolina, United States. J. of Geophys. Research, 111, C03015, doi:10.1029/2005JC003121.
Elçi, Ş., Work, P.A., and Hayter, E.J., 2007. Influence of stratification and shoreline erosion on reservoir sedimentation patterns. J. of Hydraulic Eng., ASCE, 133(3), 255-266.
Karasu, S., Work, P.A., Cambazoğlu, M.K., and Yuksek, O., 2008. Coupled longshore and cross-shore models for beach nourishment evolution at laboratory scale. J. of Waterway, Port, Coastal and Ocean Eng., ASCE, 134(1), 30-39.
Work, P.A., 2008. Nearshore directional wave measurements by surface-following buoy and acoustic Doppler current profiler. Ocean Eng., 35, Elsevier, 727-737, doi:10.1016/j.physletb.2003.10.071.
Voulgaris, G., Haus, B.K., and Work, P.A., 2008. Waves initiative within SEACOOS. Marine Technology Society Journal, special issue on Global Lessons Learned from Regional Coastal Ocean Observing Systems, 42(3), 68-80.
Elçi, Ş., Aydin, R., and Work, P.A., 2009. Estimation of suspended sediment concentration in rivers using acoustic methods. Environ Monit and Assess, 159:255-265. doi:10.1007/s10661-008-0627-5.
Ewing, L., Stauble, D.K., Work, P.A., Edge, B.L., Rogers, S.M., Loeffler, M.U., Kaihatu, J.M., Overton, M., Waters, J.P., Suzuki, K., Dean, R.G., Garrett, M.H., Wiggins, E., and Gregory, G.H., 2009. Field investigation of Hurricane Ike impacts to the upper Texas coast. Shore and Beach, 77(2), 9-23.
Work, P.A., and Srisuwan, C., 2010. Identification of swell in nearshore surface wave energy spectra. Intl. J. of Ocean and Climate Systems, 1(2), 51-66
Haus, B.K., Shay, L.K., Work, P.A., Voulgaris, G., Ramos, R.J., and Martinez-Pedraja, J., 2010. Wind speed dependence of single-site wave height retrievals from High Frequency radars. J. of Atmos and Oceanic Tech, 27(8), 1381-1394. doi: 10.1175/2010JTECHO730.1
Work, P.A., Sapp, A., Scott, D., and Dodd, M.G., 2010. Influence of small vessel operation and propulsion system on loggerhead sea turtle injuries. J. Exp Mar Biol Ecol., 393, 168-175. doi: 10.1016/j.jembe.2010.07.019
Yoo, J., Fritz, H.M., Haas, K., Work, P.A., and Barnes, C.F., 2011. Depth inversion in the surf zone with inclusion of wave nonlinearity using video-derived celerity. ASCE J. of Waterway, Port, Coastal and Ocean Eng. doi: 10.1061/(ASCE)WW.1943-5460.0000068
Ozeren, Y., Wren, D.G., Altinakar, M., and Work, P.A., 2011. Experimental investigation of cylindrical floating breakwater performance with various mooring configurations. J. of Waterway, Port, Coastal and Ocean Eng., 1(58), DOI:10.1061/(ASCE)WW.1943-5460.0000090
Work, P.A., 2011. Directional bimodality in nearshore, surface water wave energy spectra, Georgia, USA. Intl. J. of Ocean and Climate Systems, 2(3), 153-168
Work, P.A., Haas, K.A., Defne, Z., and Gay, T., 2013. Tidal stream energy site assessment via three-dimensional model and measurements. Applied Energy, 102, 510-519, http://dx.doi.org/10.1016/j.apenergy.2012.08.040
Srisuwan, C., and Work, P.A., 2013. Directional wave spectra from acoustic Doppler current profiler data in sheared and stratified flows. Ocean Engineering, 72, 149-159, http://dx.doi.org/10.1016/j.oceaneng.2013.06.003

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

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USGS Science at Work in the San Francisco Bay Estuary

In an article written for the Interagency Ecological Program for the San Francisco Estuary, Dr. Paul Work and Dr. Maureen Downing-Kunz, of the...

Read Article
USGS gage 11455820 Carquinez Strait at Carquinez Bridge near Crockett, CA Hydrologic Survey between bridge piers using a M9 ADCP
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Science and Products

  • Science
    link
    Side-looking acoustic Doppler velocity meter and water quality sonde

    State of the Network: Long-Term, High-Frequency Flow and Water Quality Data in the San Francisco Estuary, California

    The San Francisco Bay and Sacramento-San Joaquin Delta form one of the largest estuaries in the United States. Water flow and water quality in the San Francisco Bay-Delta Estuary are important to the economies of both California and the nation. The Bay-Delta system provides water to more than 25 million California residents and vast farmlands, as well as key habitat for birds, fish, and other...
    By
    California Water Science Center
    link

    State of the Network: Long-Term, High-Frequency Flow and Water Quality Data in the San Francisco Estuary, California

    The San Francisco Bay and Sacramento-San Joaquin Delta form one of the largest estuaries in the United States. Water flow and water quality in the San Francisco Bay-Delta Estuary are important to the economies of both California and the nation. The Bay-Delta system provides water to more than 25 million California residents and vast farmlands, as well as key habitat for birds, fish, and other...
    Learn More
    link
    USACE Drill Operator

    Soil Stratigraphy and Erosion Potential on the American and Sacramento Rivers

    Much of the Sacramento region is protected from flooding by levees constructed on the American and Sacramento Rivers, which join near downtown Sacramento before flowing to the Sacramento-San Joaquin River Delta.
    By
    California Water Science Center
    link

    Soil Stratigraphy and Erosion Potential on the American and Sacramento Rivers

    Much of the Sacramento region is protected from flooding by levees constructed on the American and Sacramento Rivers, which join near downtown Sacramento before flowing to the Sacramento-San Joaquin River Delta.
    Learn More
    link
    research boat on delta

    Continuous Monitoring of Water Quality and Suspended-Sediment Transport in the San Francisco Bay and Delta

    Our group at the USGS continuously monitors suspended-sediment concentration (SSC), turbidity, dissolved oxygen, temperature, salinity, and water level at many sites throughout the San Francisco Bay (Bay) and the Sacramento-San Joaquin Rivers Delta (Delta).Our work began in 1988 to explore the spatial and temporal variability of water quality and sediment transport and to provide decision makers...
    By
    California Water Science Center
    link

    Continuous Monitoring of Water Quality and Suspended-Sediment Transport in the San Francisco Bay and Delta

    Our group at the USGS continuously monitors suspended-sediment concentration (SSC), turbidity, dissolved oxygen, temperature, salinity, and water level at many sites throughout the San Francisco Bay (Bay) and the Sacramento-San Joaquin Rivers Delta (Delta).Our work began in 1988 to explore the spatial and temporal variability of water quality and sediment transport and to provide decision makers...
    Learn More
    link
    Invasive Aquatic Vegetation

    Ecosystem Engineers: Impacts of Invasive Aquatic Vegetation on the Delta’s Critical Ecosystems

    The Sacramento-San Joaquin Delta (Delta) is home to a diverse community of plants and animals and is the hub of California’s freshwater delivery system. The Delta supplies water for over 25 million Californians and supports millions of acres of farming, commercial and sport fishing, shipping and ports, and recreational boating.
    By
    California Water Science Center, Pacific Coastal and Marine Science Center
    link

    Ecosystem Engineers: Impacts of Invasive Aquatic Vegetation on the Delta’s Critical Ecosystems

    The Sacramento-San Joaquin Delta (Delta) is home to a diverse community of plants and animals and is the hub of California’s freshwater delivery system. The Delta supplies water for over 25 million Californians and supports millions of acres of farming, commercial and sport fishing, shipping and ports, and recreational boating.
    Learn More
    link
    Tule Perch

    Understanding Influences on Habitat Quality for Delta Smelt and Other Imperiled Fish Populations

    USGS scientists work to provide information needed to evaluate the efficacy of ongoing U.S. Burueau of Reclamation water management efforts in Bay-Delta.
    By
    California Water Science Center
    link

    Understanding Influences on Habitat Quality for Delta Smelt and Other Imperiled Fish Populations

    USGS scientists work to provide information needed to evaluate the efficacy of ongoing U.S. Burueau of Reclamation water management efforts in Bay-Delta.
    Learn More
  • Data

    Evaluation of Hydrodynamic Mixing in Keswick Reservoir, California, 2021-22

    California's State Water Resources Control Board (SWRCB) wishes to quantify how water and constituents introduced via the outflow from the Spring Creek Diversion Dam mix with water within Keswick Reservoir. Of primary interest is the degree of dilution that exists when this introduced flow reaches the main stem of Keswick Reservoir, and how this mixing is influenced by different operational parame
    By
    California Water Science Center

    Borehole Erosion Test data, Lower American and Sacramento Rivers, California, 2019 (ver. 3.0, July 2020)

    Borehole erosion tests were performed to quantify sediment erosion rates as a function of depth below grade and flow speed at locations along the Sacramento and American Rivers in 2019. The dataset consists of: - borehole caliper files describing the initial geometry of the borehole, and its shape after each test flow event, - where available, a digital time series describing discharge into the ho
    By
    California Water Science Center

    Sediment Concentration and Velocity Data to Assess Trapping by Submerged Vegetation

    The acoustic Doppler current meter (ADCP) used in this study outputs binary data files containing measurement scheme, location, time, velocity, backscatter, boat heading, depth, and other parameters. These data are provided here in the manufacturer's "classic ASCII" format, as described in READMEforADCP.txt file associated with this data release. We also collected water samples for suspended-sedim
    By
    California Water Science Center

    ADCP Data in Support of Water and Suspended-Sediment Flux Measurements at the Golden Gate, 2016-2017

    Field observations of water and suspended-sediment fluxes at the Golden Gate were made over one ebb tide and one flood tide on three occasions: 1) 21-22 March 2016, following a large storm event that triggered the first flow into Yolo Bypass flood control structure since 2011; 2) 23 June of 2016, during a period of low freshwater inflow and 3) 27-28 February 2017, following several large storms of
    By
    California Water Science Center
  • Publications
    Filter Total Items: 16

    Seasonal and long-term clarity trend assessment of Lake Tahoe, California–Nevada

    The clarity of Lake Tahoe, observed using a Secchi disk on a regular basis since the late 1960s, continues to be a sentinel metric of lake health. Water clarity is influenced by physical and biological processes and has declined in the five decades of monitoring, revealing differences between summer (June–September) and winter (December–March). This document summarizes key findings of a study of L
    By
    Water Resources, California Water Science Center, Nevada Water Science Center

    American and Sacramento Rivers, California, erodibility measurements and model

    Executive Summary  A previous report by the authors described sediment sampling and drilling by the U.S. Geological Survey (USGS) beside the American and Sacramento Rivers near Sacramento, California, in support of a U.S. Army Corps of Engineers project focused on regional flood control. The drilling was performed to define lithology, extract samples for laboratory testing, and perform borehole er
    By
    Water Resources, California Water Science Center

    Trapping of suspended sediment by submerged aquatic vegetation in a tidal freshwater region: Field observations and long-term trends

    Widespread invasion by non-native, submerged aquatic vegetation (SAV) may modify the sediment budget of an estuary, reducing the availability of inorganic sediment required by marshes to maintain their position in the tidal frame. The instantaneous trapping rate of suspended sediment in SAV patches in an estuary has not previously been quantified via field observations. In this study, flows of wat
    By
    Water Resources, California Water Science Center

    Sediment lithology and borehole erosion testing, American and Sacramento Rivers, California

    Executive SummaryA field investigation intended to measure the potential for erosion of sediments beside the American and Sacramento Rivers near Sacramento, California, is described. The study featured two primary components: (1) drilling and soil sampling to reveal lithology, down to depths matching the local river thalweg, where possible, and (2) borehole erosion tests (BETs) as described by Bri
    By
    Water Resources, California Water Science Center

    State of the network: Long-term, high-frequency flow and water quality data in the San Francisco Estuary, California

    The USGS California Water Science Center is heavily involved in the measurement of flow and water quality parameters in the San Francisco Estuary, with support from many partner agencies. The California Department of Water Resources (DWR), through the Interagency Ecological Program (IEP) is one of those agencies. This article describes the resulting efforts and methodologies and provides examples
    By
    Water Resources, California Water Science Center

    Stratigraphic analysis of Corte Madera Creek flood control channel deposits

    Sedimentation in a channel can reduce flood conveyance capability and potentially place nearby property and life at risk from flooding. In 1998, Marin County Public Works dredged the concrete-lined segment of Corte Madera Creek, which drains a hilly and largely urbanized watershed that terminates in San Francisco Bay, California. From then through 2015, approximately 4,100 cubic meters of sand and
    By
    Water Resources, California Water Science Center

    Measurements of erosion potential using Gust chamber in Yolo Bypass near Sacramento, California

    This report describes work performed to quantify the erodibility of surface soils in the Yolo Bypass (Bypass) near Sacramento, California, for use in the California Department of Water Resources (DWR) Yolo Bypass D-MCM mercury model. The Bypass, when not serving as a floodway, is heavily utilized for agriculture. During flood events, surface water flows over the soil, resulting in the application
    By
    Water Resources, California Water Science Center

    Erosion characteristics and horizontal variability for small erosion depths in the Sacramento-San Joaquin River Delta, California, USA

    Erodibility of cohesive sediment in the Sacramento-San Joaquin River Delta (Delta) was investigated with an erosion microcosm. Erosion depths in the Delta and in the microcosm were estimated to be about one floc diameter over a range of shear stresses and times comparable to half of a typical tidal cycle. Using the conventional assumption of horizontally homogeneous bed sediment, data from 27 of 3
    By
    Water Resources, California Water Science Center

    Record-high specific conductance and water temperature in San Francisco Bay during water year 2015

    The San Francisco estuary is commonly defined to include San Francisco Bay (bay) and the adjacent Sacramento–San Joaquin River Delta (delta). The U.S. Geological Survey (USGS) has operated a high-frequency (15-minute sampling interval) water-quality monitoring network in San Francisco Bay since the late 1980s (Buchanan and others, 2014). This network includes 19 stations at which sustained measure
    By
    Water Resources, California Water Science Center

    Acoustic Doppler velocimeter backscatter for quantification of suspended sediment concentration in South San Francisco Bay, USA

    A data set was acquired on a shallow mudflat in south San Francisco Bay that featured simultaneous, co-located optical and acoustic sensors for subsequent estimation of suspended sediment concentrations (SSC). The optical turbidity sensor output was converted to SSC via an empirical relation derived at a nearby site using bottle sample estimates of SSC. The acoustic data was obtained using an acou
    By
    Water Resources, California Water Science Center

    Beach nourishment alternative assessment to constrain cross-shore and longshore sediment transport

    A combined field and laboratory investigation was conducted to assess five options for creation of a recreational beach on a steep, armored shoreline on the eastern Black Sea coast. All designs incorporated a beach nourishment project placed between two existing, shore-normal, rubble-mound groins. Alternatives included the placement of a nearshore berm, longshore extensions added to the existing g
    By
    Water Resources, California Water Science Center

    Innovation in monitoring: The U.S. Geological Survey Sacramento–San Joaquin River Delta, California, flow-station network

    The U.S. Geological Survey (USGS) installed the first gage to measure the flow of water into California’s Sacramento–San Joaquin River Delta from the Sacramento River in the late 1800s. Today, a network of 35 hydro-acoustic meters measure flow throughout the delta. This region is a critical part of California’s freshwater supply and conveyance system. With the data provided by this flow-station ne
    By
    Water Resources, California Water Science Center

    Non-USGS Publications**

    Work, P.A., and Dean, R.G, 1995. Assessment and prediction of beach nourishment evolution. J. Waterway, Port, Coastal, and Ocean Eng., 121(3), American Soc. of Civil Eng. (ASCE), New York, NY, 182-189.
    Dean, R.G., and Work, P.A., 1993. Interaction of navigational entrances with adjacent shorelines. J. Coastal Res., SI 18, 91-110.
    Hansen, M.E., and Work, P.A., 1997. Short- and Long-term variability of ebb-tidal delta shoals: management implications. Eos, Transactions American Geophysical Union, 78(46), Nov. 18, 1997.
    Work, P.A., and Kaihatu, J.M., 1997. Wave transformation at Pensacola Pass, FL: Field and numerical model results. J. Waterway, Port, Coastal, and Ocean Eng., 123(6), ASCE, New York, NY, 314-321.
    Work, P.A., and Rogers, W.E., 1997. Wave transformation for beach nourishment projects. Coastal Eng., 32(1), Elsevier, Amsterdam, 1-18.
    Work, P.A., Hansen, M., and Rogers, W.E., 1998. Bathymetric surveying with GPS technology and heave, pitch, and roll compensation, J. Surveying Eng., 124(2), ASCE, 73-90.
    Work, P.A., and Rogers, W.E., 1998. Laboratory study of beach nourishment behavior. J. Waterway, Port, Coastal, and Ocean Eng., 124(5), ASCE, New York, NY, 229-237.
    Atanov, G.A., Evseeva, E.G., and Work, P.A., 1998. The variational problem of water level stabilization in open channels. J. Hydraulic Eng., 124(1), ASCE, New York, NY, 50-54.
    Work, P.A. Rogers, S.M., Jr., and Osborne, R., 1999. Retrofit superelevation of coastal residential structures. J. Water Resources Planning and Management, 125(2), ASCE, New York, NY, 88-93.
    Kana, T.W., Hayter, E.J., and Work, P.A., 1999. Mesoscale sediment transport at Southeastern U.S. tidal inlets: conceptual model applicable to mixed energy settings. J. Coastal Res., 15(2), 303-313.
    Work, P.A., Guan, J., Hayter, E.J., and Elçi, Ş., 2001. Mesoscale model for morphologic change at tidal inlets. J. of Waterway, Port, Coastal and Ocean Eng., 127(5), ASCE, 282-289.
    Work, P.A., Moore, P., and Reible, D.D., 2002. Bioturbation, advection and diffusion of a conserved contaminant in a laboratory flume. AGU J. of Water Resources Res., 38(6), 24-1-24-9.
    Work, P.A., Fehrenbacher, F., and Voulgaris, G., 2004. Nearshore impacts of dredging for beach nourishment. J. of Waterway, Port, Coastal and Ocean Eng., 130(6), ASCE, 303-311.
    Demir, H., Otay, E., Work, P., and Borekçi, O., 2004. Shoreline change due to nearshore dredging. J. of Waterway, Port, Coastal and Ocean Eng., ASCE, 130(4), 170-178.
    Gutierrez, B.T., Voulgaris, G., and Work, P.A., 2006. Cross-shore variation of wind-driven flows on the inner shelf in Long Bay, South Carolina, United States. J. of Geophys. Research, 111, C03015, doi:10.1029/2005JC003121.
    Elçi, Ş., Work, P.A., and Hayter, E.J., 2007. Influence of stratification and shoreline erosion on reservoir sedimentation patterns. J. of Hydraulic Eng., ASCE, 133(3), 255-266.
    Karasu, S., Work, P.A., Cambazoğlu, M.K., and Yuksek, O., 2008. Coupled longshore and cross-shore models for beach nourishment evolution at laboratory scale. J. of Waterway, Port, Coastal and Ocean Eng., ASCE, 134(1), 30-39.
    Work, P.A., 2008. Nearshore directional wave measurements by surface-following buoy and acoustic Doppler current profiler. Ocean Eng., 35, Elsevier, 727-737, doi:10.1016/j.physletb.2003.10.071.
    Voulgaris, G., Haus, B.K., and Work, P.A., 2008. Waves initiative within SEACOOS. Marine Technology Society Journal, special issue on Global Lessons Learned from Regional Coastal Ocean Observing Systems, 42(3), 68-80.
    Elçi, Ş., Aydin, R., and Work, P.A., 2009. Estimation of suspended sediment concentration in rivers using acoustic methods. Environ Monit and Assess, 159:255-265. doi:10.1007/s10661-008-0627-5.
    Ewing, L., Stauble, D.K., Work, P.A., Edge, B.L., Rogers, S.M., Loeffler, M.U., Kaihatu, J.M., Overton, M., Waters, J.P., Suzuki, K., Dean, R.G., Garrett, M.H., Wiggins, E., and Gregory, G.H., 2009. Field investigation of Hurricane Ike impacts to the upper Texas coast. Shore and Beach, 77(2), 9-23.
    Work, P.A., and Srisuwan, C., 2010. Identification of swell in nearshore surface wave energy spectra. Intl. J. of Ocean and Climate Systems, 1(2), 51-66
    Haus, B.K., Shay, L.K., Work, P.A., Voulgaris, G., Ramos, R.J., and Martinez-Pedraja, J., 2010. Wind speed dependence of single-site wave height retrievals from High Frequency radars. J. of Atmos and Oceanic Tech, 27(8), 1381-1394. doi: 10.1175/2010JTECHO730.1
    Work, P.A., Sapp, A., Scott, D., and Dodd, M.G., 2010. Influence of small vessel operation and propulsion system on loggerhead sea turtle injuries. J. Exp Mar Biol Ecol., 393, 168-175. doi: 10.1016/j.jembe.2010.07.019
    Yoo, J., Fritz, H.M., Haas, K., Work, P.A., and Barnes, C.F., 2011. Depth inversion in the surf zone with inclusion of wave nonlinearity using video-derived celerity. ASCE J. of Waterway, Port, Coastal and Ocean Eng. doi: 10.1061/(ASCE)WW.1943-5460.0000068
    Ozeren, Y., Wren, D.G., Altinakar, M., and Work, P.A., 2011. Experimental investigation of cylindrical floating breakwater performance with various mooring configurations. J. of Waterway, Port, Coastal and Ocean Eng., 1(58), DOI:10.1061/(ASCE)WW.1943-5460.0000090
    Work, P.A., 2011. Directional bimodality in nearshore, surface water wave energy spectra, Georgia, USA. Intl. J. of Ocean and Climate Systems, 2(3), 153-168
    Work, P.A., Haas, K.A., Defne, Z., and Gay, T., 2013. Tidal stream energy site assessment via three-dimensional model and measurements. Applied Energy, 102, 510-519, http://dx.doi.org/10.1016/j.apenergy.2012.08.040
    Srisuwan, C., and Work, P.A., 2013. Directional wave spectra from acoustic Doppler current profiler data in sheared and stratified flows. Ocean Engineering, 72, 149-159, http://dx.doi.org/10.1016/j.oceaneng.2013.06.003

    **Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

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    USGS Science at Work in the San Francisco Bay Estuary

    In an article written for the Interagency Ecological Program for the San Francisco Estuary, Dr. Paul Work and Dr. Maureen Downing-Kunz, of the...

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  • Multimedia
    USGS gage 11455820 Carquinez Strait at Carquinez Bridge near Crockett, CA Hydrologic Survey between bridge piers using a M9 ADCP
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*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government