USGS employees Kurt Weidich, Paul Buchanan, and Maureen Downing-Kunz conduct a Hydrologic Survey between bridge piers using a M9 Acoustic Doplar Current Profiler (ADCP), at USGS gage11455820 Carquinez Strait at Carquinez Bridge near Crockett, CA.
Paul Work, Ph.D., P.E., D.CE (Former Employee)
Science and Products
Evaluation of Hydrodynamic Mixing in Keswick Reservoir, California
Flow and Water Quality Data in the San Francisco Estuary
Soil Stratigraphy and Erosion Potential on the American and Sacramento Rivers
Continuous Monitoring of Water Quality and Suspended-Sediment Transport in the San Francisco Bay and Delta
Ecosystem Engineers: Impacts of Invasive Aquatic Vegetation on the Delta’s Critical Ecosystems
Understanding Influences on Habitat Quality for Delta Smelt and Other Imperiled Fish Populations
Model Archive Summary for Surrogate Turbidity Regression at USGS station 11455780 Suisun Bay at Benicia Bridge near Benicia CA (Upper Sensor), Water Years 2018, 2019, and 2020
Keswick Reservoir, California, Delft3D-FM Model Archive
Evaluation of Hydrodynamic Mixing in Keswick Reservoir, California, 2021-22
Borehole Erosion Test data, Lower American and Sacramento Rivers, California, 2019 (ver. 3.0, July 2020)
Sediment Concentration and Velocity Data to Assess Trapping by Submerged Vegetation
ADCP Data in Support of Water and Suspended-Sediment Flux Measurements at the Golden Gate, 2016-2017
Gust Erosion Chamber Data, Yolo Bypass, CA (2015-16)
USGS employees Kurt Weidich, Paul Buchanan, and Maureen Downing-Kunz conduct a Hydrologic Survey between bridge piers using a M9 Acoustic Doplar Current Profiler (ADCP), at USGS gage11455820 Carquinez Strait at Carquinez Bridge near Crockett, CA.
Evaluation of hydrodynamic mixing in an afterbay reservoir
Seasonal and long-term clarity trend assessment of Lake Tahoe, California–Nevada
Risk-informed levee erosion countermeasure site selection and design in the Sacramento area part 1: Soil sampling, testing, and data processing
Risk-informed levee erosion countermeasure site selection and design in the Sacramento area part 2: Probabilistic numerical simulation of bank erosion
American and Sacramento Rivers, California, erodibility measurements and model
Trapping of suspended sediment by submerged aquatic vegetation in a tidal freshwater region: Field observations and long-term trends
Sediment lithology and borehole erosion testing, American and Sacramento Rivers, California
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
Stratigraphic analysis of Corte Madera Creek flood control channel deposits
Measurements of erosion potential using Gust chamber in Yolo Bypass near Sacramento, California
Erosion characteristics and horizontal variability for small erosion depths in the Sacramento-San Joaquin River Delta, California, USA
Record-high specific conductance and water temperature in San Francisco Bay during water year 2015
Non-USGS Publications**
**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.
Science and Products
- Science
Evaluation of Hydrodynamic Mixing in Keswick Reservoir, California
Keswick Reservoir, on the Sacramento River, receives both water and contaminants from the Spring Creek Debris Dam. The term contaminants refers here to different kinds of chemicals that are in some instances delivered to lakes and rivers. These chemicals can have a detrimental effect on drinking water supplies and the health of humans, fish, and other aquatic species.Flow and Water Quality Data in the San Francisco Estuary
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...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.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...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.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. - Data
Model Archive Summary for Surrogate Turbidity Regression at USGS station 11455780 Suisun Bay at Benicia Bridge near Benicia CA (Upper Sensor), Water Years 2018, 2019, and 2020
Model for computing point estimates of continuous 15-minute time-series suspended-sediment concentration data from instream turbidity data. Turbidity data is published in NWIS. Model is based on data from WY2015-2020 and applies beginning Water Year 2018 (1 October 2017).Keswick Reservoir, California, Delft3D-FM Model Archive
Application of Delft3D-FM model to Keswick Reservoir in California, for short-term (days) simulations. Model archive includes source code (open-source, created by Deltares in the Netherlands), input files, and output files in netCDF format. Source code will need to be compiled for the operating system and hardware being used. Instructions are included with the source code. A separate data releaseEvaluation 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 parameBorehole 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 hoSediment 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-sedimADCP 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 ofGust Erosion Chamber Data, Yolo Bypass, CA (2015-16)
A Gust erosion chamber was used to apply horizontal shear stress to sediment cores obtained at selected locations within the Yolo Bypass near Sacramento, California. The locations correspond to different land uses; two cores were taken at each site. The shear stress was increased in stepwise fashion, and turbidity of the effluent monitored. From this, two quantities are calculated: 1) critical she - Multimedia
Surveying At USGS Gage 11455820 Carquinez Strait At Carquinez Bridge.Surveying At USGS Gage 11455820 Carquinez Strait At Carquinez Bridge.
USGS employees Kurt Weidich, Paul Buchanan, and Maureen Downing-Kunz conduct a Hydrologic Survey between bridge piers using a M9 Acoustic Doplar Current Profiler (ADCP), at USGS gage11455820 Carquinez Strait at Carquinez Bridge near Crockett, CA.
USGS employees Kurt Weidich, Paul Buchanan, and Maureen Downing-Kunz conduct a Hydrologic Survey between bridge piers using a M9 Acoustic Doplar Current Profiler (ADCP), at USGS gage11455820 Carquinez Strait at Carquinez Bridge near Crockett, CA.
- Publications
Filter Total Items: 19
Evaluation of hydrodynamic mixing in an afterbay reservoir
This study focused on the mixing of a solute, assumed to be conservative, introduced to one arm of an afterbay reservoir, between Keswick and Shasta Dams on the Sacramento River near Redding, California. Rhodamine water tracer (WT) dye served as the solute in a field experiment, and was introduced over 4.5 h and monitored for 4 days by sondes moored in the reservoir. The scenario was modeled numerAuthorsPaul WorkSeasonal 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 LAuthorsRamon C. Naranjo, Paul Work, Alan Heyvaert, Geoffrey Schladow, Alicia Cortes, Shohei Watanabe, Lidia Tanaka, Sebnem ElciRisk-informed levee erosion countermeasure site selection and design in the Sacramento area part 1: Soil sampling, testing, and data processing
USACE partnered with the United States Department of Agriculture, Agricultural Research Service, United States Geological Survey, and Texas A&M University to evaluate the erodibility of the river banks and levees to inform probabilistic numerical simulations using the Bank Stability and Toe Erosion Model (BSTEM). This paper discusses the measurement of the intrinsic erosion and geotechnical properAuthorsTodd M. Rivas, Jonathan AuBuchon, Anna Shidlovskaya, Eddy J. Langendoen, Paul A. Work, Daniel N. Livsey, Anna Timchenko, Jean-Louis BriaudRisk-informed levee erosion countermeasure site selection and design in the Sacramento area part 2: Probabilistic numerical simulation of bank erosion
USACE partnered with the United States Department of Agriculture, Agricultural Research Service, United States Geological Survey, and Texas A&M University to evaluate the erodibility of the river banks and levees to inform probabilistic numerical simulations using the Bank Stability and Toe Erosion Model (BSTEM). This paper, the second of two parts, addresses processing the collected data to inforAuthorsTodd M. Rivas, Jonathan AuBuchon, Anna Shidlovskaya, Eddy J. Langendoen, Paul A. Work, Daniel N. Livsey, Anna Timchenko, Kellie Jemes, Jean-Louis BriaudAmerican 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 erAuthorsPaul A. Work, Daniel N. LivseyTrapping 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 watAuthorsPaul A. Work, Maureen A. Downing-Kunz, Judith Z. DrexlerSediment 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 BriAuthorsPaul A. Work, Daniel N. LivseyState 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
AuthorsPaul A. Work, Maureen A. Downing-KunzStratigraphic 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 andAuthorsDaniel N. Livsey, Paul A. Work, Maureen A. Downing-KunzMeasurements 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 applicationAuthorsPaul A. Work, David H. SchoellhamerErosion 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 3AuthorsDavid H. Schoellhamer, Andrew J. Manning, Paul A. WorkRecord-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 measureAuthorsPaul A. Work, Maureen A. Downing-Kunz, Daniel N. LivseyNon-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), 51-66Haus, 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: 10.1175/2010JTECHO730.1Work, 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.2010.07.019Yoo, 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.1943-5460.0000068Ozeren, 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.1943-5460.0000090Work, P.A., 2011. Directional bimodality in nearshore, surface water wave energy spectra, Georgia, USA. Intl. J. of Ocean and Climate Systems, 2(3), 153-168Work, 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.2012.08.040Srisuwan, 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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*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