Pete Lenaker is a Physical Scientist with the Upper Midwest Water Science Center.
Education and Certifications
M.S. in Oceanography and Coastal Sciences, Louisiana State University, 2009
B.S. in Environmental Science, Western Washington University - Huxley College of the Environment, 2006
A.A. in Environmental Studies, North Seattle College, 2003
Science and Products
MMSD Watercourse Corridor Study: Contaminants in Water and Sediment
There are many kinds of chemical, physical, and biological contaminants contained in water and sediment, and new or “emerging” contaminants are continually being discovered. USGS investigations of contaminants in the MMSD Watercourse Corridor Study include studies of PFAS, PAHs, microplastics, and wastewater contamination as well as modeling long-term trends in water quality.
Human and Bovine Virus Prevalence in Some Great Lakes Tributaries Influenced by Watershed-Specific and Seasonal Characteristics
Human enteric and bovine-specific viruses were detected in eight Great Lakes tributaries. Presence and concentration of human viruses increased in watersheds with greater than 25 percent urban influence and more than 2,900 people per square kilometer. Similarly, bovine viruses increased in watersheds having greater than 40 percent agricultural land influence and cattle densities greater than 50...
Select optical signals from water samples collected on the Menomonee River, Underwood Creek, and Jones Island Water Reclamation Facility from 2017-2019, and time-series optical sensor and one-hour mean streamflow data from the Menomonee River 2017-2018
5-day composite river water samples were collected from two sites: Menomonee River (U.S. Geological Survey station number 04087142) and Underwood Creek (U.S. Geological Survey station number 04087088) in Milwaukee, Wisconsin. 5-day composite wastewater (raw sewage) influent samples were also collected from the Jones Island Water Reclamation Facility (U.S. Geological Survey station number 430125087
Great Lakes tributary pharmaceutical water samples from water year 2018
This data release provides water chemistry results and quality assurance data for samples collected from Great Lakes tributaries in the states of Minnesota, Wisconsin, Michigan, Indiana, Ohio, and New York. In total, 158 chemicals were analyzed which are primarily pharmaceuticals. Between one and four water samples were collected at 37 sampling locations between November 2017 and July 2018 resulti
Optical signals of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water of Great Lake tributaries from 2011 to 2016
Data are from water samples collected from tributaries of the Great Lakes at three different drainage basin scales, including 1). watershed scale: 8 tributaries of the Great Lakes, 2). subwatershed scale: 5 locations from the greater Milwaukee, Wisconsin area, and 3). small scale: 213 storm sewers and open channel locations in three subwatersheds within the Great Lakes Basin including the Middle B
Microplastics in the water column and sediment in Milwaukee-Area streams, the Milwaukee Harbor, and Lake Michigan, 2016
This dataset describes the quantity, morphology, and polymer identity of microplastics in the water column and surficial sediments of Milwaukee-Area streams, the Milwaukee Harbor, and Lake Michigan (Wisconsin). Water samples were collected at 10 locations, 2-4 times each, from May to September, 2016. At the 4 shallowest locations, water was collected only at the water surface. At the remaining 6 l
Microplastics in the surficial benthic sediment from Lake Michigan and Lake Erie, 2013 and 2014
This dataset describes the quantity, morphology, concentration and polymer identity of microplastics in surficial benthic sediment of Lake Michigan and Lake Erie. Lake Michigan sediment samples were collected at 20 locations in September, 2013 and Lake Erie sediment samples were collected at 12 locations in September, 2014 while on-board the R.V. Lake Guardian. Sampling and analysis methods are de
Human-associated indicator bacteria and human specific virus loads, sample volumes, and drainage areas for six Menomonee River Watershed sampling locations
Human-associated indicator bacteria and human specific viruses in the Menomonee River watershed in Milwaukee, WI were investigated from April 2009 to March 2011 at six sampling locations within the watershed. We used concentration and water volume data from runoff-event and low-flow periods to compute loads for each sample collected, and subsequently used those loads, and drainage area from each
Modeled predictions of human-associated and fecal-indicator bacteria concentrations and loadings in the Menomonee River, Wisconsin using in-situ optical sensors
Human sewage contamination of waterways is a major issue in the United States and throughout the world. Models were developed for estimation of two human-associated fecal-indicator and three general fecal-indicator bacteria (HIB and FIB) using in situ optical field-sensor data for estimating concentrations and loads of HIB and FIB and the extent of sewage contamination in the Menomonee River in Mi
Authors
Peter L. Lenaker, Steven R. Corsi, Laura A. DeCicco, Hayley T. Olds, Debra K. Dila, Mari Danz, Sandra L. McLellan, Troy D. Rutter
Prioritizing pharmaceutical contaminants in Great Lakes tributaries using risk-based screening techniques
In a study of 44 diverse sampling sites across 16 Great Lakes tributaries, 110 pharmaceuticals were detected of 257 monitored. The present study evaluated the ecological relevance of detected chemicals and identified heavily impacted areas to help inform resource managers and guide future investigations. Ten pharmaceuticals (caffeine, nicotine, albuterol, sulfamethoxazole, venlafaxine, acetaminoph
Authors
Matthew A. Pronschinske, Steven R. Corsi, Laura A. DeCicco, Edward Furlong, Gerald T. Ankley, Brett R. Blackwell, Daniel L. Villeneuve, Peter L. Lenaker, Michelle A. Nott
Risk-based prioritization of organic chemicals and locations of ecological concern in sediment from Great Lakes tributaries
With improved analytical techniques, environmental monitoring studies are increasingly able to report the occurrence of tens or hundreds of chemicals per site, making it difficult to identify the most relevant chemicals from a biological standpoint. For this study, organic chemical occurrence was examined, individually and as mixtures, in the context of potential biological effects. Sediment was c
Authors
Austin K. Baldwin, Steven R. Corsi, Owen M. Stefaniak, Luke C. Loken, Daniel L. Villeneuve, Gerald T. Ankley, Brett R. Blackwell, Peter L. Lenaker, Michelle A. Nott, Marc A. Mills
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, and ofte
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
Spatial distribution of microplastics in surficial benthic sediment of Lake Michigan and Lake Erie
The spatial distribution, concentration, particle size, and polymer compositions of microplastics in Lake Michigan and Lake Erie sediment were investigated. Fibers/lines were the most abundant of the five particle types characterized. Microplastic particles were observed in all samples with mean concentrations for particles greater than 0.355 mm of 65.2 p kg–1 in Lake Michigan samples (n = 20) and
Authors
Peter L. Lenaker, Steven R. Corsi, Sherri A. Mason
Primary sources of polycyclic aromatic hydrocarbons to streambed sediment in Great Lakes tributaries using multiple lines of evidence
Polycyclic aromatic hydrocarbons (PAHs) are among the most widespread and potentially toxic contaminants in Great Lakes (USA/Canada) tributaries. The sources of PAHs are numerous and diverse, and identifying the primary source(s) can be difficult. The present study used multiple lines of evidence to determine the likely sources of PAHs to surficial streambed sediments at 71 locations across 26 Gre
Authors
Austin K. Baldwin, Steven R. Corsi, Samantha K. Oliver, Peter L. Lenaker, Michelle A. Nott, Marc A. Mills, Gary A. Norris, Pentti Paatero
Vertical distribution of microplastics in the water column and surficial sediment from the Milwaukee River basin to Lake Michigan
Microplastic contamination was studied along a freshwater continuum from inland streams to the Milwaukee River estuary to Lake Michigan, and vertically from the water surface, water subsurface and sediment. Microplastics were detected in all 96 water samples and nine sediment samples collected. Results indicated a gradient of polymer presence with depth: low-density particles decreased from water
Authors
Peter L. Lenaker, Austin K. Baldwin, Steven R. Corsi, Sherri A. Mason, Paul Reneau, John W Scott
Human-associated indicator bacteria and human-specific viruses in surface water: a spatial assessment with implications on fate and transport
Hydrologic, seasonal, and spatial variability of sewage contamination was studied at six locations within a watershed upstream from water reclamation facility (WRF) effluent to define relative loadings of sewage from different portions of the watershed. Fecal pollution from human sources was spatially quantified by measuring two human-associated indicator bacteria (HIB) and eight human-specific vi
Authors
Peter L. Lenaker, Steven R. Corsi, Sandra L. McLellan, Mark A. Borchardt, Hayley T. Olds, Deborah K. Dila, Susan K. Spencer, Austin K. Baldwin
Patterns of host-associated fecal indicators driven by hydrology, precipitation, and land use attributes in Great Lakes watersheds
Fecal contamination from sewage and agricultural runoff is a pervasive problem in Great Lakes watersheds. Most work examining fecal pollution loads relies on discrete samples of fecal indicators and modeling land use. In this study, we made empirical measurements of human and ruminant-associated fecal indicator bacteria and combined these with hydrological measurements in eight watersheds ranging
Authors
Deborah K. Dila, Steven R. Corsi, Peter L. Lenaker, Austin K. Baldwin, Melinda J. Bootsma, Sandra L. McLellan
Hydrologic, land cover, and seasonal patterns of waterborne pathogens in Great Lakes tributaries
Great Lakes tributaries are known to deliver waterborne pathogens from a host of sources. To examine the hydrologic, land cover, and seasonal patterns of waterborne pathogens (i.e. protozoa (2), pathogenic bacteria (4) human viruses, (8) and bovine viruses (8)) eight rivers were monitored in the Great Lakes Basin over 29 months from February 2011 to June 2013. Sampling locations represented a wide
Authors
Peter L. Lenaker, Steven R. Corsi, Mark A. Borchardt, Susan K. Spencer, Austin K. Baldwin, Michelle A. Lutz
Organic contaminants in Great Lakes tributaries: Prevalence and potential aquatic toxicity
Organic compounds used in agriculture, industry, and households make their way into surface waters through runoff, leaking septic-conveyance systems, regulated and unregulated discharges, and combined sewer overflows, among other sources. Concentrations of these organic waste compounds (OWCs) in some Great Lakes tributaries indicate a high potential for adverse impacts on aquatic organisms. During
Authors
Austin K. Baldwin, Steven R. Corsi, Laura A. De Cicco, Peter L. Lenaker, Michelle A. Lutz, Daniel J. Sullivan, Kevin D. Richards
Non-USGS Publications**
Rivera-Monroy, V.H., Lenaker, P., Twilley, R.R., Delaune, R.D., Lindau, C.W., Nuttle, W., Habib, E., Fulweiler, R.W., Castaneda-Moya, E. (2010) Denitrification in coastal Louisiana: A Spatial Assessment and Research Needs. Journal of Sea Research 63 (3-4): 157-172.
**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
MMSD Watercourse Corridor Study: Contaminants in Water and Sediment
There are many kinds of chemical, physical, and biological contaminants contained in water and sediment, and new or “emerging” contaminants are continually being discovered. USGS investigations of contaminants in the MMSD Watercourse Corridor Study include studies of PFAS, PAHs, microplastics, and wastewater contamination as well as modeling long-term trends in water quality.Human and Bovine Virus Prevalence in Some Great Lakes Tributaries Influenced by Watershed-Specific and Seasonal Characteristics
Human enteric and bovine-specific viruses were detected in eight Great Lakes tributaries. Presence and concentration of human viruses increased in watersheds with greater than 25 percent urban influence and more than 2,900 people per square kilometer. Similarly, bovine viruses increased in watersheds having greater than 40 percent agricultural land influence and cattle densities greater than 50... - Data
Select optical signals from water samples collected on the Menomonee River, Underwood Creek, and Jones Island Water Reclamation Facility from 2017-2019, and time-series optical sensor and one-hour mean streamflow data from the Menomonee River 2017-2018
5-day composite river water samples were collected from two sites: Menomonee River (U.S. Geological Survey station number 04087142) and Underwood Creek (U.S. Geological Survey station number 04087088) in Milwaukee, Wisconsin. 5-day composite wastewater (raw sewage) influent samples were also collected from the Jones Island Water Reclamation Facility (U.S. Geological Survey station number 430125087Great Lakes tributary pharmaceutical water samples from water year 2018
This data release provides water chemistry results and quality assurance data for samples collected from Great Lakes tributaries in the states of Minnesota, Wisconsin, Michigan, Indiana, Ohio, and New York. In total, 158 chemicals were analyzed which are primarily pharmaceuticals. Between one and four water samples were collected at 37 sampling locations between November 2017 and July 2018 resultiOptical signals of water for prediction of wastewater contamination, human-associated bacteria, and fecal indicator bacteria in surface water of Great Lake tributaries from 2011 to 2016
Data are from water samples collected from tributaries of the Great Lakes at three different drainage basin scales, including 1). watershed scale: 8 tributaries of the Great Lakes, 2). subwatershed scale: 5 locations from the greater Milwaukee, Wisconsin area, and 3). small scale: 213 storm sewers and open channel locations in three subwatersheds within the Great Lakes Basin including the Middle BMicroplastics in the water column and sediment in Milwaukee-Area streams, the Milwaukee Harbor, and Lake Michigan, 2016
This dataset describes the quantity, morphology, and polymer identity of microplastics in the water column and surficial sediments of Milwaukee-Area streams, the Milwaukee Harbor, and Lake Michigan (Wisconsin). Water samples were collected at 10 locations, 2-4 times each, from May to September, 2016. At the 4 shallowest locations, water was collected only at the water surface. At the remaining 6 lMicroplastics in the surficial benthic sediment from Lake Michigan and Lake Erie, 2013 and 2014
This dataset describes the quantity, morphology, concentration and polymer identity of microplastics in surficial benthic sediment of Lake Michigan and Lake Erie. Lake Michigan sediment samples were collected at 20 locations in September, 2013 and Lake Erie sediment samples were collected at 12 locations in September, 2014 while on-board the R.V. Lake Guardian. Sampling and analysis methods are deHuman-associated indicator bacteria and human specific virus loads, sample volumes, and drainage areas for six Menomonee River Watershed sampling locations
Human-associated indicator bacteria and human specific viruses in the Menomonee River watershed in Milwaukee, WI were investigated from April 2009 to March 2011 at six sampling locations within the watershed. We used concentration and water volume data from runoff-event and low-flow periods to compute loads for each sample collected, and subsequently used those loads, and drainage area from each - Multimedia
- Publications
Modeled predictions of human-associated and fecal-indicator bacteria concentrations and loadings in the Menomonee River, Wisconsin using in-situ optical sensors
Human sewage contamination of waterways is a major issue in the United States and throughout the world. Models were developed for estimation of two human-associated fecal-indicator and three general fecal-indicator bacteria (HIB and FIB) using in situ optical field-sensor data for estimating concentrations and loads of HIB and FIB and the extent of sewage contamination in the Menomonee River in MiAuthorsPeter L. Lenaker, Steven R. Corsi, Laura A. DeCicco, Hayley T. Olds, Debra K. Dila, Mari Danz, Sandra L. McLellan, Troy D. RutterPrioritizing pharmaceutical contaminants in Great Lakes tributaries using risk-based screening techniques
In a study of 44 diverse sampling sites across 16 Great Lakes tributaries, 110 pharmaceuticals were detected of 257 monitored. The present study evaluated the ecological relevance of detected chemicals and identified heavily impacted areas to help inform resource managers and guide future investigations. Ten pharmaceuticals (caffeine, nicotine, albuterol, sulfamethoxazole, venlafaxine, acetaminophAuthorsMatthew A. Pronschinske, Steven R. Corsi, Laura A. DeCicco, Edward Furlong, Gerald T. Ankley, Brett R. Blackwell, Daniel L. Villeneuve, Peter L. Lenaker, Michelle A. NottRisk-based prioritization of organic chemicals and locations of ecological concern in sediment from Great Lakes tributaries
With improved analytical techniques, environmental monitoring studies are increasingly able to report the occurrence of tens or hundreds of chemicals per site, making it difficult to identify the most relevant chemicals from a biological standpoint. For this study, organic chemical occurrence was examined, individually and as mixtures, in the context of potential biological effects. Sediment was cAuthorsAustin K. Baldwin, Steven R. Corsi, Owen M. Stefaniak, Luke C. Loken, Daniel L. Villeneuve, Gerald T. Ankley, Brett R. Blackwell, Peter L. Lenaker, Michelle A. Nott, Marc A. MillsOptical 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, and ofteAuthorsSteven 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. McLellanSpatial distribution of microplastics in surficial benthic sediment of Lake Michigan and Lake Erie
The spatial distribution, concentration, particle size, and polymer compositions of microplastics in Lake Michigan and Lake Erie sediment were investigated. Fibers/lines were the most abundant of the five particle types characterized. Microplastic particles were observed in all samples with mean concentrations for particles greater than 0.355 mm of 65.2 p kg–1 in Lake Michigan samples (n = 20) andAuthorsPeter L. Lenaker, Steven R. Corsi, Sherri A. MasonPrimary sources of polycyclic aromatic hydrocarbons to streambed sediment in Great Lakes tributaries using multiple lines of evidence
Polycyclic aromatic hydrocarbons (PAHs) are among the most widespread and potentially toxic contaminants in Great Lakes (USA/Canada) tributaries. The sources of PAHs are numerous and diverse, and identifying the primary source(s) can be difficult. The present study used multiple lines of evidence to determine the likely sources of PAHs to surficial streambed sediments at 71 locations across 26 GreAuthorsAustin K. Baldwin, Steven R. Corsi, Samantha K. Oliver, Peter L. Lenaker, Michelle A. Nott, Marc A. Mills, Gary A. Norris, Pentti PaateroVertical distribution of microplastics in the water column and surficial sediment from the Milwaukee River basin to Lake Michigan
Microplastic contamination was studied along a freshwater continuum from inland streams to the Milwaukee River estuary to Lake Michigan, and vertically from the water surface, water subsurface and sediment. Microplastics were detected in all 96 water samples and nine sediment samples collected. Results indicated a gradient of polymer presence with depth: low-density particles decreased from waterAuthorsPeter L. Lenaker, Austin K. Baldwin, Steven R. Corsi, Sherri A. Mason, Paul Reneau, John W ScottHuman-associated indicator bacteria and human-specific viruses in surface water: a spatial assessment with implications on fate and transport
Hydrologic, seasonal, and spatial variability of sewage contamination was studied at six locations within a watershed upstream from water reclamation facility (WRF) effluent to define relative loadings of sewage from different portions of the watershed. Fecal pollution from human sources was spatially quantified by measuring two human-associated indicator bacteria (HIB) and eight human-specific viAuthorsPeter L. Lenaker, Steven R. Corsi, Sandra L. McLellan, Mark A. Borchardt, Hayley T. Olds, Deborah K. Dila, Susan K. Spencer, Austin K. BaldwinPatterns of host-associated fecal indicators driven by hydrology, precipitation, and land use attributes in Great Lakes watersheds
Fecal contamination from sewage and agricultural runoff is a pervasive problem in Great Lakes watersheds. Most work examining fecal pollution loads relies on discrete samples of fecal indicators and modeling land use. In this study, we made empirical measurements of human and ruminant-associated fecal indicator bacteria and combined these with hydrological measurements in eight watersheds rangingAuthorsDeborah K. Dila, Steven R. Corsi, Peter L. Lenaker, Austin K. Baldwin, Melinda J. Bootsma, Sandra L. McLellanHydrologic, land cover, and seasonal patterns of waterborne pathogens in Great Lakes tributaries
Great Lakes tributaries are known to deliver waterborne pathogens from a host of sources. To examine the hydrologic, land cover, and seasonal patterns of waterborne pathogens (i.e. protozoa (2), pathogenic bacteria (4) human viruses, (8) and bovine viruses (8)) eight rivers were monitored in the Great Lakes Basin over 29 months from February 2011 to June 2013. Sampling locations represented a wideAuthorsPeter L. Lenaker, Steven R. Corsi, Mark A. Borchardt, Susan K. Spencer, Austin K. Baldwin, Michelle A. LutzOrganic contaminants in Great Lakes tributaries: Prevalence and potential aquatic toxicity
Organic compounds used in agriculture, industry, and households make their way into surface waters through runoff, leaking septic-conveyance systems, regulated and unregulated discharges, and combined sewer overflows, among other sources. Concentrations of these organic waste compounds (OWCs) in some Great Lakes tributaries indicate a high potential for adverse impacts on aquatic organisms. DuringAuthorsAustin K. Baldwin, Steven R. Corsi, Laura A. De Cicco, Peter L. Lenaker, Michelle A. Lutz, Daniel J. Sullivan, Kevin D. RichardsNon-USGS Publications**
Rivera-Monroy, V.H., Lenaker, P., Twilley, R.R., Delaune, R.D., Lindau, C.W., Nuttle, W., Habib, E., Fulweiler, R.W., Castaneda-Moya, E. (2010) Denitrification in coastal Louisiana: A Spatial Assessment and Research Needs. Journal of Sea Research 63 (3-4): 157-172.**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.
- News