Hydrologist and Water Quality Specialist for the Washington Water Science Center
My research focuses on the occurrence, fate, and transport of contaminants in the aquatic environment. Recent activities and interests include:
- Developing novel field methods to quantify fluvial sediment-bound chemical concentrations and fluxes from rivers to Puget Sound
- Entry and movement of urban contaminants in nearshore coastal environments
- Monitoring of legacy contaminants (e.g., PCBs and metals), emerging contaminants (e.g., microplastics and endocrine-disrupting chemicals), and microbial contaminants (e.g., bacteria, viruses, and fecal indicators) in aquatic resources with implications for ecological and human health
- Providing technical guidance for water-quality projects, including study design, data quality, and dissemination
Professional Experience
Hydrologist with the U.S. Geological Survey's Washington Water Science Center since 2011 and the Center's Water-Quality Specialist since 2015.
Education and Certifications
B.S. in Chemistry from the College of William & Mary
M.S. and Ph.D. in Environmental Science & Engineering from the Colorado School of Mines
Post-doctoral research at the University of North Carolina's Institute of Marine Sciences.
Science and Products
The 150th anniversary of the 1869 Powell expedition—USGS participation in the Sesquicentennial Colorado River Exploring Expedition and reflections from the ~1,000-mile journey down the Green and Colorado Rivers
Maternal transfer of polychlorinated biphenyls in Pacific sand lance (Ammodytes personatus), Puget Sound, Washington
Legacy and current-use toxic contaminants in Pacific sand lance (Ammodytes personatus) from Puget Sound, Washington
Evidence for rapid gut clearance of microplastic polyester fibers fed to Chinook Salmon: A tank study
Microplastic concentrations in two Oregon bivalve species: Spatial, temporal, and species variability
Characterization and load estimation of polychlorinated biphenyls (PCBs) from selected Rio Grande tributary stormwater channels in the Albuquerque urbanized area, New Mexico, 2017–18
Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and metals in ambient sediment at mussel biomonitoring sites, Puget Sound, Washington
Caged mussels used as biomonitors can provide insights about ambient contaminant assemblages and spatial patterns, sources of contaminants, and contaminant exposure risks for consumers of wild and farmed mussels. This study explored the potential role of ambient sediment in the uptake of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and potentially toxic inorganic elem
Data management plan for the U.S. Geological Survey Washington Water Science Center
Sources, timing, and fate of sediment and contaminants in the nearshore: insights from geochemistry
Rivers in Cascade watersheds carry sediment with a volcanic composition that is distinct from the plutonic composition of the Puget lowlands. Compositional properties (signatures) allow discrimination of river-sourced Cascade from lowland sediment, and inferences about transport pathways. Surface sediment on land contains atmospheric radionuclides whose known decay rates define monthly (7Be) and d
Assessment of existing groundwater quality data in the Green-Duwamish watershed, Washington
Hydrology-driven chemical loads transported by the Green River to the Lower Duwamish Waterway near Seattle, Washington, 2013–17
Tidal flushing of mercury from the Bremerton Naval Complex through the PSNS015 stormwater drain system to Sinclair Inlet, Kitsap County, Washington, 2011 -12
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.
Coastal Habitats in Puget Sound
Contaminants in Puget Sound Forage Fishes and Impacts to the Marine Food Web
USGS Tacoma Seminar Series
River Loads into Puget Sound
Sources of Mercury in Sinclair Inlet Project
Particulate mercury isotope results, fiber optic thermal survey data, and nearshore surface sediment results at the Bremerton Naval Complex, Washington, USA, 2020-21
Counts, Fish Weights, and Spectral Data from a Juvenile Chinook Salmon Polyester Microplastic Fiber Exposure Study
Maternal transfer of PCBs in Pacific sand lance in Puget Sound, Washington
Groundwater and Tidal Time-Series Data, Bremerton Naval Complex, Bremerton Washington
Science and Products
- Publications
Filter Total Items: 26
The 150th anniversary of the 1869 Powell expedition—USGS participation in the Sesquicentennial Colorado River Exploring Expedition and reflections from the ~1,000-mile journey down the Green and Colorado Rivers
In 1869, John Wesley Powell completed the first well-recorded scientific river journey to explore an extensive region of the Colorado River Basin. Powell later helped to establish the U.S. Geological Survey (USGS) and served as its second director (1881–94), cementing his position in the folklore of the Survey. In 2019, the USGS marked the 150th anniversary of Powell’s first expedition with a broaAuthorsAnnie Scott, Eleanour SnowMaternal transfer of polychlorinated biphenyls in Pacific sand lance (Ammodytes personatus), Puget Sound, Washington
We measured polychlorinated biphenyls (PCBs) in multiple age and size classes of Pacific sand lance (Ammodytes personatus), including eggs, young-of-the year, and adults to evaluate maternal transfer as a pathway for contaminant uptake and to add to the limited information on the occurrence of PCBs in sand lance in Puget Sound. Sampling was replicated at an urban embayment (Eagle Harbor) and a staAuthorsTheresa L. Liedtke, Kathleen E. ConnLegacy and current-use toxic contaminants in Pacific sand lance (Ammodytes personatus) from Puget Sound, Washington
Forage fish are primary prey for seabirds, fish and marine mammals. Elevated levels of pollutants in Puget Sound, Washington salmon and killer whale tissues potentially could be sufficiently high to elicit adverse effects and hamper population recovery efforts. Contaminant transfer and biomagnification of the toxic compounds measured in this study likely contribute to those elevated concentrationsAuthorsKathleen E. Conn, Theresa L. Liedtke, Renee K. Takesue, Richard S. DinicolaEvidence for rapid gut clearance of microplastic polyester fibers fed to Chinook Salmon: A tank study
Marine and freshwater plastic pollution is a challenging issue receiving large amounts of research and media attention. Yet, few studies have documented the impact of microplastic ingestion to aquatic organisms. In the Pacific Northwest, Chinook salmon are a culturally and commercially significant fish species. The presence of marine and freshwater microplastic pollution is well documented in ChinAuthorsAndrew Spanjer, Theresa L. Liedtke, Kathleen E. Conn, Lisa K. Weiland, Robert W. Black, Nathan GodfreyMicroplastic concentrations in two Oregon bivalve species: Spatial, temporal, and species variability
Microplastics are an ecological stressor with implications for ecosystem and human health when present in seafood. We quantified microplastic types, concentrations, anatomical burdens, geographic distribution, and temporal differences in Pacific oysters (Crassostrea gigas) and Pacific razor clams (Siliqua patula) from 15 Oregon coast, U.S.A. sites. Microplastics were present in organisms from allAuthorsBritta Baechler, Elise F. Granek, Matthew G. Hunter, Kathleen E. ConnCharacterization and load estimation of polychlorinated biphenyls (PCBs) from selected Rio Grande tributary stormwater channels in the Albuquerque urbanized area, New Mexico, 2017–18
In cooperation with the New Mexico County of Bernalillo, the U.S. Geological Survey characterized potential polychlorinated biphenyl (PCB) concentration and estimated loading into the Rio Grande from watersheds that are under the county’s jurisdiction. Water and sediment samples were collected in 2017–18 from six sites within four stormwater drainage basins in the Albuquerque, New Mexico, urbanizeAuthorsZachary M. Shephard, Kathleen E. Conn, Kimberly R. Beisner, Alanna D. Jornigan, Christina F. BryantPolycyclic aromatic hydrocarbons, polychlorinated biphenyls, and metals in ambient sediment at mussel biomonitoring sites, Puget Sound, Washington
Caged mussels used as biomonitors can provide insights about ambient contaminant assemblages and spatial patterns, sources of contaminants, and contaminant exposure risks for consumers of wild and farmed mussels. This study explored the potential role of ambient sediment in the uptake of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and potentially toxic inorganic elem
AuthorsRenee K. Takesue, Pamela L. Campbell‐Swarzenski, Kathleen E. ConnData management plan for the U.S. Geological Survey Washington Water Science Center
The primary mission of the U.S. Geological Survey (USGS) Water Mission Area is to collect and disseminate reliable, impartial, and timely information needed to understand the water resources of the Nation, including data on streamflow, groundwater, water quality, water use, and availability. Management of data throughout the entire data lifecycle is necessary to meet the mission and maintain the UAuthorsKathleen E. Conn, Mark C. Mastin, Andrew J. Long, Richard S. Dinicola, Cynthia BartonSources, timing, and fate of sediment and contaminants in the nearshore: insights from geochemistry
Rivers in Cascade watersheds carry sediment with a volcanic composition that is distinct from the plutonic composition of the Puget lowlands. Compositional properties (signatures) allow discrimination of river-sourced Cascade from lowland sediment, and inferences about transport pathways. Surface sediment on land contains atmospheric radionuclides whose known decay rates define monthly (7Be) and d
AuthorsRenee K. Takesue, Kathleen E. Conn, Margaret DutchAssessment of existing groundwater quality data in the Green-Duwamish watershed, Washington
The United States Geological Survey (USGS) provided technical support to the Washington Department of Ecology (Ecology) in their assessment of the role groundwater plays in contributing pollutant loading to the Green-Duwamish River near Seattle, Washington. Ecology is developing watershed hydrology models of the Green-Duwamish watershed, and need to assign realistic contaminant concentrations to tAuthorsCraig A. Senter, Kathleen E. Conn, Robert W. Black, Wendy B. Welch, Elisabeth T. FasserHydrology-driven chemical loads transported by the Green River to the Lower Duwamish Waterway near Seattle, Washington, 2013–17
The sediments in the Lower Duwamish Waterway Superfund site in Seattle, Washington, are contaminated with chemicals including metals such as arsenic, polychlorinated biphenyls (PCBs), carcinogenic polycyclic aromatic hydrocarbons (cPAHs), and dioxins/furans from decades of intense anthropogenic activities. The U.S. Geological Survey, in cooperation with the Washington State Department of Ecology,AuthorsKathleen E. Conn, Robert W. Black, Craig A. Senter, Norman T. Peterson, Ann Vanderpool-KimuraTidal flushing of mercury from the Bremerton Naval Complex through the PSNS015 stormwater drain system to Sinclair Inlet, Kitsap County, Washington, 2011 -12
The sediments of Sinclair Inlet, in Puget Sound, Washington, have elevated levels of contaminants including mercury. The Bremerton Naval Complex is adjacent to Sinclair Inlet, and has known areas of historical soil mercury contamination. The U.S. Geological Survey, in cooperation with the U.S. Navy, has been investigating the potential for mercury sources on the Bremerton Naval Complex to recontamAuthorsKathleen E. Conn, Anthony J. Paulson, Richard S. Dinicola, John F. DeWildNon-USGS Publications**
Habteselassie, M.Y., Kirs, M., Conn, K.E., Blackwood, A.D., Kelly, G. and Noble, R.T. (2011), Tracking microbial transport through four onsite wastewater treatment systems to receiving waters in eastern North Carolina. Journal of Applied Microbiology, 111: 835–847. doi:10.1111/j.1365-2672.2011.05105.xConn, K.E., Lowe, K.S., Drewes, J.E., Hoppe-Jones, C., Tucholke, M.B., 2010, Environmental Engineering Science, 27(4): 347-356, https://doi.org/10.1089/ees.2009.0364Conn, K. E., Siegrist, R. L., Barber, L. B. and Meyer, M. T. (2010), Fate of trace organic compounds during vadose zone soil treatment in an onsite wastewater system. Environmental Toxicology and Chemistry, 29: 285–293. doi:10.1002/etc.40Lowe, K.S., Tucholke, M.B., Tomaras, J.M.B., Conn, K., Hoppe, C., Drewes, J.E., McCray, J.E., Munakata-Marr, J., 2009, Influent Constituent Characteristics of the Modern Waste Stream from Single Sources: Final Report. Water Environment Research Foundation. 04-DEC-1. 206 pg., www.ndwrcdp.org/publications.Lowe, K.S., Rothe, N., Tomaras, J., Conn, K., Tucholke, M., Drewes, J., McCray, J., Munakata-Marr, J., 2007, Influent Constituent Characteristics of the Modern Waste Stream from Single Sources: Literature Review. Water Environment Research Foundation. 04-DEC-1a. 89 pg. PDF available at www.ndwrcdp.org/publications.Conn, K.E., Siegrist, R.L., Barber, L.B., Brown, G.K. Organic contaminants in onsite wastewater treatment systems. In Proceedings of the 11th National Symposium on Individual and Small Community Sewage Systems. October 20-24, 2007. Warwick, RI: American Society of Agricultural and Biological Engineers: St. Joseph, MI, 701P1107cd.**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
Coastal Habitats in Puget Sound
A Pacific Northwest icon, Puget Sound is the second-largest estuary in the United States. Its unique geology, climate, and nutrient-rich waters produce and sustain biologically productive coastal habitats. These same natural characteristics also contribute to a high quality of life that has led to growth in human population and urbanization. This growth has played a role in degrading the Sound...Contaminants in Puget Sound Forage Fishes and Impacts to the Marine Food Web
Toxic chemical pollutants have been released into Puget Sound for decades by human activities. There’s a wide range of contaminants, from persistent compounds like polychlorinated biphenyls (PCBs) and flame retardants to contaminants of emerging concern. Aquatic species can be exposed to and accumulate contaminants, causing disease or disruption of biological processes like growth or reproduction...USGS Tacoma Seminar Series
Please note, the seminars are suspended until further notice. Our lunchtime "brownbag" seminars are held Tuesdays from 12pm to 1 pm unless otherwise noted. The science lectures are held at the USGS Washington Water Science Center at 934 Broadway, Suite 300, Tacoma, WA. The presentations are informal and are open to the public. Please, bring your lunch.River Loads into Puget Sound
The Issue: Puget Sound, WA, is the second largest estuary in the United States and its unique geology, climate, and nutrient-rich waters sustain biologically-productive terrestrial, coastal, and marine habitats. Development and associated human activities have significantly degraded the Sound, causing declines in fish and wildlife populations, water-quality issues, and losses of critical habitats...Sources of Mercury in Sinclair Inlet Project
The sediments in Sinclair Inlet within Puget Sound, Washington have elevated concentrations of a number of organic compounds and elements including mercury. Following remediation actions under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), it was determined that there is insufficient information to determine whether remedial action taken at OU B Marine with... - Data
Particulate mercury isotope results, fiber optic thermal survey data, and nearshore surface sediment results at the Bremerton Naval Complex, Washington, USA, 2020-21
This data release contains four data sets that support ongoing U.S. Geological Survey investigations, in cooperation with the U.S. Navy, at the Bremerton Naval Complex (BNC), Sinclair Inlet, Washington. Child item #1 includes reported concentrations of mercury isotopes in 28 samples of new (2018-19) or archived (2008-09) particulate samples from the BNC, surface sediment from Sinclair Inlet, or suCounts, Fish Weights, and Spectral Data from a Juvenile Chinook Salmon Polyester Microplastic Fiber Exposure Study
This release includes all data collected in support of a juvenile Chinook salmon exposure study designed to understand the retention of microplastic clothing fibers (hereon referred to as "microfibers") after feeding. To understand the potential impacts of microfiber ingestion to fish, we ran a feeding experiment with juvenile Chinook salmon to determine if ingested fibers are retained and/or digeMaternal transfer of PCBs in Pacific sand lance in Puget Sound, Washington
Data included in this release are from Pacific sand lance and water, sediment and suspended particulate matter collected at two sites in Puget Sound, Washington, which were evaluated for PCB concentration. PCB congener data are stored in the U.S. Fish and Wildlife Service's Environmental Contaminant Data Management System (ECDMS), accessible through the Wildlife & Environmental Contaminants MapperGroundwater and Tidal Time-Series Data, Bremerton Naval Complex, Bremerton Washington
This data release includes time series data collected at the Bremerton Naval Complex, Bremerton WA. Groundwater levels and water quality parameters in two monitoring wells were recorded every 15 minutes during a 7-month deployment. Time series data were collected from June 29, 2018, to February 26, 2019. Field deployment details and quality assurance methods are included in the following paragraph - Multimedia
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