Angela Hansen
Angela Hansen - California Water Science Center
My research focuses on source and cycling of organic carbon in aquatic environments. Much of my current work involves the investigation of organic matter optical properties–as measured by absorbance and fluorescence–to demonstrate the utility of these measurements as proxies for organic compounds (i.e. DBPs, oil/gas, wastewater, Hg, etc.). I also supervise our group’s Organic Matter Research Laboratory.
Science and Products
Filter Total Items: 36
Water-quality data including mercury and methylmercury at selected sites in the Cache Creek watershed, Yolo County, California Water-quality data including mercury and methylmercury at selected sites in the Cache Creek watershed, Yolo County, California
This dataset includes water-quality and sediment data for 647 environmental samples collected at 53 surface-water sites in Cache Creek (Cache C) watershed, Yolo County, California, between December 2009 and April 2019, and data for 190 associated quality-control samples (replicates and blanks). About 90 percent of the samples were collected at the following six primary sites that were...
Laboratory optical measurements to assess long-term changes in water-extractable soil organic matter, U.S. Great Plains Laboratory optical measurements to assess long-term changes in water-extractable soil organic matter, U.S. Great Plains
Carbon (C) and nitrogen (N) extracted from soil with water are associated with available plant nutrients and microbial activity, but information about how C and N have changed over time in the U.S. Great Plains is sparse. Optical measurements of absorbance and fluorescence were used to compare dissolved organic matter (DOM) extracted from historic (1947) and contemporary (2018) soil...
Environmental Sampling and Modeling Results to Characterize Surface-Water Quality at 32 Sites Across the Potomac River Watershed, 2022 (ver. 3.0, April 2025) Environmental Sampling and Modeling Results to Characterize Surface-Water Quality at 32 Sites Across the Potomac River Watershed, 2022 (ver. 3.0, April 2025)
This data release presents chemical results from investigations of surface-water quality in the Potomac River watershed (encompassing Washington, D.C. and parts of West Virginia, Virginia, Pennsylvania, and Maryland) conducted during low-flow conditions in July through September of 2022 and modeling results that support interpretative products. Water-quality sampling: A sampling campaign...
Laboratory-based optical measurements for surface water samples collected within the Fraser River in the Upper Colorado River Basin from September 2021 through September 2023 Laboratory-based optical measurements for surface water samples collected within the Fraser River in the Upper Colorado River Basin from September 2021 through September 2023
Optical spectra reported here are collected from 17 surface water sampling sites within the Fraser River, a headwaters drainage of the Upper Colorado River Basin in the central western United States. The sample collection was conducted as part of the partnership between the United States Geological Survey’s (USGS) Next Generation Water Observation System (NGWOS) and Proxies Project, in
2022 Organic Matter Research Lab Sacramento, California Vectorized Fluorescence Data 2022 Organic Matter Research Lab Sacramento, California Vectorized Fluorescence Data
The U.S. Geological Survey (USGS) California Water Science Center (CAWSC) Organic Matter Research Laboratory (OMRL) provides laboratory services and support to regional and national projects in the analysis of organic matter using the latest methods in absorbance and fluorescence spectroscopy. Optical measurements such as absorbance and fluorescence are used to gain insight into...
2022 Organic Matter Research Lab Sacramento, California Full Spectra Absorbance Data 2022 Organic Matter Research Lab Sacramento, California Full Spectra Absorbance Data
The U.S. Geological Survey (USGS) California Water Science Center (CAWSC) Organic Matter Research Laboratory (OMRL) provides laboratory services and support to regional and national projects in the analysis of organic matter using the latest methods in absorbance and fluorescence spectroscopy. Optical measurements such as absorbance and fluorescence are used to gain insight into...
Filter Total Items: 15
Spectral characterization of dissolved organic matter in groundwater to assess mixing with oil-field water near selected oil fields, southern California Spectral characterization of dissolved organic matter in groundwater to assess mixing with oil-field water near selected oil fields, southern California
Samples of oil-field water (oil wells, injectate, disposal ponds) and groundwater near selected oil and gas fields in southern California were analyzed for dissolved organic carbon (DOC) concentration and by optical spectroscopic techniques (i.e., absorbance and fluorescence) to assess whether these measurements can be used to distinguish between oil-field water (Oil Field), native...
Authors
Angela Hansen, Tamara E. C. Kraus, Matthew K. Landon, Peter B. McMahon
Field techniques for fluorescence measurements targeting dissolved organic matter, hydrocarbons, and wastewater in environmental waters: Principles and guidelines for instrument selection, operation and maintenance, quality assurance, and data reporting Field techniques for fluorescence measurements targeting dissolved organic matter, hydrocarbons, and wastewater in environmental waters: Principles and guidelines for instrument selection, operation and maintenance, quality assurance, and data reporting
The use of field deployable fluorescence sensors by the U.S. Geological Survey has become increasingly common for a wide variety of surface water and groundwater investigations. This report addresses field deployable fluorometers that measure the fluorescence response of various substances in water exposed to incident light generated by the sensor. An introduction to the basic principles...
Authors
Amanda Booth, Jacob Fleck, Brian A. Pellerin, Angela Hansen, Alexandra Etheridge, Guy M. Foster, Jennifer L. Graham, Brian A. Bergamaschi, Kurt D. Carpenter, Bryan D. Downing, Stewart A. Rounds, JohnFranco Saraceno
Sources and characteristics of dissolved organic carbon in the McKenzie River, Oregon, related to the formation of disinfection by-products in treated drinking water Sources and characteristics of dissolved organic carbon in the McKenzie River, Oregon, related to the formation of disinfection by-products in treated drinking water
Executive Summary This study characterized the concentration and quality of dissolved organic carbon (DOC) in the McKenzie River, a relatively undeveloped watershed in western Oregon, and its link to forming disinfection by-products (DBPs) in treated drinking water. The study aimed to identify the primary source(s) of DOC in source water for the Eugene Water & Electric Board’s (EWEB)...
Authors
Kurt D. Carpenter, Tamara E. C. Kraus, Angela M. Hansen, Bryan D. Downing, Jami H. Goldman, Jonathan Haynes, David Donahue, Karl Morgenstern
Optical properties of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water at three watershed scales Optical properties of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water at three watershed scales
Relations between spectral absorbance and fluorescence properties of water and human-associated and fecal indicator bacteria were developed for facilitating field sensor applications to estimate wastewater contamination in waterways. Leaking wastewater conveyance infrastructure commonly contaminates receiving waters. Methods to quantify such contamination can be time consuming, expensive...
Authors
Steven R. Corsi, Laura A. DeCicco, Angela Hansen, Peter L. Lenaker, Brian A. Bergamaschi, Brian A. Pellerin, Debra Dila, Melinda Bootsma, Susan Spencer, Mark A. Borchardt, Sandra L. McLellan
An initial comparison of pesticides and amphibian pathogens between natural and created wetlands in the New Jersey Pinelands, 2014–16 An initial comparison of pesticides and amphibian pathogens between natural and created wetlands in the New Jersey Pinelands, 2014–16
A study conducted by the U.S. Geological Survey, in cooperation with the New Jersey Pinelands Commission and Montclair State University, was designed to compare pesticide concentrations and the presence and prevalence of amphibian pathogens between natural ponds and two types of created wetlands, excavated ponds and stormwater basins, throughout the New Jersey Pinelands. The study...
Authors
Kelly L. Smalling, John F. Bunnell, Jonathan Cohl, Kristin M. Romanok, Lisa Hazard, Kirsten Monsen, Denise M. Akob, Angela M. Hansen, Michelle L. Hladik, Nicole Abdallah, Quratulain Ahmed, Araba Assan, Matthew D. De Parsia, Amaryl Griggs, Megan McWayne-Holmes, Naisargi Patel, Corey Sanders, Yesha Shrestha, Sean M. Stout, Brianna Williams
Procedures for using the Horiba Scientific Aqualog® fluorometer to measure absorbance and fluorescence from dissolved organic matter Procedures for using the Horiba Scientific Aqualog® fluorometer to measure absorbance and fluorescence from dissolved organic matter
Advances in spectroscopic techniques have led to an increase in the use of optical measurements (absorbance and fluorescence) to assess dissolved organic matter composition and infer sources and processing. Although optical measurements are easy to make, they can be affected by many variables rendering them less comparable, including by inconsistencies in sample collection (for example...
Authors
Angela M. Hansen, Jacob Fleck, Tamara E. C. Kraus, Bryan D. Downing, Travis von Dessonneck, Brian A. Bergamaschi
Science and Products
Filter Total Items: 36
Water-quality data including mercury and methylmercury at selected sites in the Cache Creek watershed, Yolo County, California Water-quality data including mercury and methylmercury at selected sites in the Cache Creek watershed, Yolo County, California
This dataset includes water-quality and sediment data for 647 environmental samples collected at 53 surface-water sites in Cache Creek (Cache C) watershed, Yolo County, California, between December 2009 and April 2019, and data for 190 associated quality-control samples (replicates and blanks). About 90 percent of the samples were collected at the following six primary sites that were...
Laboratory optical measurements to assess long-term changes in water-extractable soil organic matter, U.S. Great Plains Laboratory optical measurements to assess long-term changes in water-extractable soil organic matter, U.S. Great Plains
Carbon (C) and nitrogen (N) extracted from soil with water are associated with available plant nutrients and microbial activity, but information about how C and N have changed over time in the U.S. Great Plains is sparse. Optical measurements of absorbance and fluorescence were used to compare dissolved organic matter (DOM) extracted from historic (1947) and contemporary (2018) soil...
Environmental Sampling and Modeling Results to Characterize Surface-Water Quality at 32 Sites Across the Potomac River Watershed, 2022 (ver. 3.0, April 2025) Environmental Sampling and Modeling Results to Characterize Surface-Water Quality at 32 Sites Across the Potomac River Watershed, 2022 (ver. 3.0, April 2025)
This data release presents chemical results from investigations of surface-water quality in the Potomac River watershed (encompassing Washington, D.C. and parts of West Virginia, Virginia, Pennsylvania, and Maryland) conducted during low-flow conditions in July through September of 2022 and modeling results that support interpretative products. Water-quality sampling: A sampling campaign...
Laboratory-based optical measurements for surface water samples collected within the Fraser River in the Upper Colorado River Basin from September 2021 through September 2023 Laboratory-based optical measurements for surface water samples collected within the Fraser River in the Upper Colorado River Basin from September 2021 through September 2023
Optical spectra reported here are collected from 17 surface water sampling sites within the Fraser River, a headwaters drainage of the Upper Colorado River Basin in the central western United States. The sample collection was conducted as part of the partnership between the United States Geological Survey’s (USGS) Next Generation Water Observation System (NGWOS) and Proxies Project, in
2022 Organic Matter Research Lab Sacramento, California Vectorized Fluorescence Data 2022 Organic Matter Research Lab Sacramento, California Vectorized Fluorescence Data
The U.S. Geological Survey (USGS) California Water Science Center (CAWSC) Organic Matter Research Laboratory (OMRL) provides laboratory services and support to regional and national projects in the analysis of organic matter using the latest methods in absorbance and fluorescence spectroscopy. Optical measurements such as absorbance and fluorescence are used to gain insight into...
2022 Organic Matter Research Lab Sacramento, California Full Spectra Absorbance Data 2022 Organic Matter Research Lab Sacramento, California Full Spectra Absorbance Data
The U.S. Geological Survey (USGS) California Water Science Center (CAWSC) Organic Matter Research Laboratory (OMRL) provides laboratory services and support to regional and national projects in the analysis of organic matter using the latest methods in absorbance and fluorescence spectroscopy. Optical measurements such as absorbance and fluorescence are used to gain insight into...
Filter Total Items: 15
Spectral characterization of dissolved organic matter in groundwater to assess mixing with oil-field water near selected oil fields, southern California Spectral characterization of dissolved organic matter in groundwater to assess mixing with oil-field water near selected oil fields, southern California
Samples of oil-field water (oil wells, injectate, disposal ponds) and groundwater near selected oil and gas fields in southern California were analyzed for dissolved organic carbon (DOC) concentration and by optical spectroscopic techniques (i.e., absorbance and fluorescence) to assess whether these measurements can be used to distinguish between oil-field water (Oil Field), native...
Authors
Angela Hansen, Tamara E. C. Kraus, Matthew K. Landon, Peter B. McMahon
Field techniques for fluorescence measurements targeting dissolved organic matter, hydrocarbons, and wastewater in environmental waters: Principles and guidelines for instrument selection, operation and maintenance, quality assurance, and data reporting Field techniques for fluorescence measurements targeting dissolved organic matter, hydrocarbons, and wastewater in environmental waters: Principles and guidelines for instrument selection, operation and maintenance, quality assurance, and data reporting
The use of field deployable fluorescence sensors by the U.S. Geological Survey has become increasingly common for a wide variety of surface water and groundwater investigations. This report addresses field deployable fluorometers that measure the fluorescence response of various substances in water exposed to incident light generated by the sensor. An introduction to the basic principles...
Authors
Amanda Booth, Jacob Fleck, Brian A. Pellerin, Angela Hansen, Alexandra Etheridge, Guy M. Foster, Jennifer L. Graham, Brian A. Bergamaschi, Kurt D. Carpenter, Bryan D. Downing, Stewart A. Rounds, JohnFranco Saraceno
Sources and characteristics of dissolved organic carbon in the McKenzie River, Oregon, related to the formation of disinfection by-products in treated drinking water Sources and characteristics of dissolved organic carbon in the McKenzie River, Oregon, related to the formation of disinfection by-products in treated drinking water
Executive Summary This study characterized the concentration and quality of dissolved organic carbon (DOC) in the McKenzie River, a relatively undeveloped watershed in western Oregon, and its link to forming disinfection by-products (DBPs) in treated drinking water. The study aimed to identify the primary source(s) of DOC in source water for the Eugene Water & Electric Board’s (EWEB)...
Authors
Kurt D. Carpenter, Tamara E. C. Kraus, Angela M. Hansen, Bryan D. Downing, Jami H. Goldman, Jonathan Haynes, David Donahue, Karl Morgenstern
Optical properties of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water at three watershed scales Optical properties of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water at three watershed scales
Relations between spectral absorbance and fluorescence properties of water and human-associated and fecal indicator bacteria were developed for facilitating field sensor applications to estimate wastewater contamination in waterways. Leaking wastewater conveyance infrastructure commonly contaminates receiving waters. Methods to quantify such contamination can be time consuming, expensive...
Authors
Steven R. Corsi, Laura A. DeCicco, Angela Hansen, Peter L. Lenaker, Brian A. Bergamaschi, Brian A. Pellerin, Debra Dila, Melinda Bootsma, Susan Spencer, Mark A. Borchardt, Sandra L. McLellan
An initial comparison of pesticides and amphibian pathogens between natural and created wetlands in the New Jersey Pinelands, 2014–16 An initial comparison of pesticides and amphibian pathogens between natural and created wetlands in the New Jersey Pinelands, 2014–16
A study conducted by the U.S. Geological Survey, in cooperation with the New Jersey Pinelands Commission and Montclair State University, was designed to compare pesticide concentrations and the presence and prevalence of amphibian pathogens between natural ponds and two types of created wetlands, excavated ponds and stormwater basins, throughout the New Jersey Pinelands. The study...
Authors
Kelly L. Smalling, John F. Bunnell, Jonathan Cohl, Kristin M. Romanok, Lisa Hazard, Kirsten Monsen, Denise M. Akob, Angela M. Hansen, Michelle L. Hladik, Nicole Abdallah, Quratulain Ahmed, Araba Assan, Matthew D. De Parsia, Amaryl Griggs, Megan McWayne-Holmes, Naisargi Patel, Corey Sanders, Yesha Shrestha, Sean M. Stout, Brianna Williams
Procedures for using the Horiba Scientific Aqualog® fluorometer to measure absorbance and fluorescence from dissolved organic matter Procedures for using the Horiba Scientific Aqualog® fluorometer to measure absorbance and fluorescence from dissolved organic matter
Advances in spectroscopic techniques have led to an increase in the use of optical measurements (absorbance and fluorescence) to assess dissolved organic matter composition and infer sources and processing. Although optical measurements are easy to make, they can be affected by many variables rendering them less comparable, including by inconsistencies in sample collection (for example...
Authors
Angela M. Hansen, Jacob Fleck, Tamara E. C. Kraus, Bryan D. Downing, Travis von Dessonneck, Brian A. Bergamaschi