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Peter L Lenaker

Pete Lenaker is a Supervisory Physical Scientist and Water Quality Assessment Team Lead 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

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 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...
By
Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center
Filter Total Items: 25
Custom-designed net for sampling microplastics at depth, Lake Michigan
Custom-designed net for sampling microplastics at depth, Lake Michigan
Custom-designed net for sampling microplastics at depth, Lake Michigan
Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan.

By
Upper Midwest Water Science Center
Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan.

By
Upper Midwest Water Science Center
Sediment core from Kinnickinnic River
Sediment core from Kinnickinnic River
Sediment core from Kinnickinnic River
Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River.

By
Upper Midwest Water Science Center
Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River.

By
Upper Midwest Water Science Center
View of suspension bridge above lake
Hoan Bridge in Milwaukee, Wisconsin
Hoan Bridge in Milwaukee, Wisconsin
View of suspension bridge above lake

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisocnsin with Lake Michigan in the background, taken from Inner Milwaukee Harbor.

By
Upper Midwest Water Science Center, Upper Midwest Water Science Center
View of suspension bridge above lake

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisocnsin with Lake Michigan in the background, taken from Inner Milwaukee Harbor.

By
Upper Midwest Water Science Center, Upper Midwest Water Science Center
Scientist collecting an Equal Width Increment (EWI) sample
Scientist collecting an Equal Width Increment (EWI) sample
Scientist collecting an Equal Width Increment (EWI) sample
Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

USGS scientist collecting an Equal width increment (EWI) sample on Bark River, Merton, WI.

By
Upper Midwest Water Science Center
Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

USGS scientist collecting an Equal width increment (EWI) sample on Bark River, Merton, WI.

By
Upper Midwest Water Science Center
Filter Total Items: 14

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
By
Water Resources Mission Area, California Water Science Center, Upper Midwest Water Science Center

Spatial distribution of microplastics in surficial benthic sediment of Lake Michigan and Lake Erie 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...
Authors
Peter L. Lenaker, Steven R. Corsi, Sherri A. Mason
By
Upper Midwest Water Science Center

Primary sources of polycyclic aromatic hydrocarbons to streambed sediment in Great Lakes tributaries using multiple lines of evidence 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...
Authors
Austin K. Baldwin, Steven R. Corsi, Samantha K. Oliver, Peter L. Lenaker, Michelle A. Nott, Marc A. Mills, Gary A. Norris, Pentti Paatero
By
Water Resources Mission Area, Idaho Water Science Center, Upper Midwest Water Science Center

Vertical distribution of microplastics in the water column and surficial sediment from the Milwaukee River basin to Lake Michigan 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...
Authors
Peter L. Lenaker, Austin K. Baldwin, Steven R. Corsi, Sherri A. Mason, Paul C. Reneau, John W Scott
By
Water Resources Mission Area, Upper Midwest Water Science Center, Idaho Water Science Center

Human-associated indicator bacteria and human-specific viruses in surface water: a spatial assessment with implications on fate and transport 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...
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
By
Upper Midwest Water Science Center

Patterns of host-associated fecal indicators driven by hydrology, precipitation, and land use attributes in Great Lakes watersheds 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...
Authors
Deborah K. Dila, Steven R. Corsi, Peter L. Lenaker, Austin K. Baldwin, Melinda J. Bootsma, Sandra L. McLellan
By
Upper Midwest Water Science Center

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

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 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...
By
Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center
Filter Total Items: 25
Custom-designed net for sampling microplastics at depth, Lake Michigan
Custom-designed net for sampling microplastics at depth, Lake Michigan
Custom-designed net for sampling microplastics at depth, Lake Michigan
Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan.

By
Upper Midwest Water Science Center
Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan

Custom-designed net for sampling microplastics at depth, Lake Michigan.

By
Upper Midwest Water Science Center
Sediment core from Kinnickinnic River
Sediment core from Kinnickinnic River
Sediment core from Kinnickinnic River
Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River.

By
Upper Midwest Water Science Center
Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River

Sediment core from Kinnickinnic River.

By
Upper Midwest Water Science Center
View of suspension bridge above lake
Hoan Bridge in Milwaukee, Wisconsin
Hoan Bridge in Milwaukee, Wisconsin
View of suspension bridge above lake

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisocnsin with Lake Michigan in the background, taken from Inner Milwaukee Harbor.

By
Upper Midwest Water Science Center, Upper Midwest Water Science Center
View of suspension bridge above lake

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisconsin

Hoan Bridge in Milwaukee, Wisocnsin with Lake Michigan in the background, taken from Inner Milwaukee Harbor.

By
Upper Midwest Water Science Center, Upper Midwest Water Science Center
Scientist collecting an Equal Width Increment (EWI) sample
Scientist collecting an Equal Width Increment (EWI) sample
Scientist collecting an Equal Width Increment (EWI) sample
Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

USGS scientist collecting an Equal width increment (EWI) sample on Bark River, Merton, WI.

By
Upper Midwest Water Science Center
Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

Scientist collecting an Equal Width Increment (EWI) sample

USGS scientist collecting an Equal width increment (EWI) sample on Bark River, Merton, WI.

By
Upper Midwest Water Science Center
Filter Total Items: 14

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
By
Water Resources Mission Area, California Water Science Center, Upper Midwest Water Science Center

Spatial distribution of microplastics in surficial benthic sediment of Lake Michigan and Lake Erie 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...
Authors
Peter L. Lenaker, Steven R. Corsi, Sherri A. Mason
By
Upper Midwest Water Science Center

Primary sources of polycyclic aromatic hydrocarbons to streambed sediment in Great Lakes tributaries using multiple lines of evidence 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...
Authors
Austin K. Baldwin, Steven R. Corsi, Samantha K. Oliver, Peter L. Lenaker, Michelle A. Nott, Marc A. Mills, Gary A. Norris, Pentti Paatero
By
Water Resources Mission Area, Idaho Water Science Center, Upper Midwest Water Science Center

Vertical distribution of microplastics in the water column and surficial sediment from the Milwaukee River basin to Lake Michigan 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...
Authors
Peter L. Lenaker, Austin K. Baldwin, Steven R. Corsi, Sherri A. Mason, Paul C. Reneau, John W Scott
By
Water Resources Mission Area, Upper Midwest Water Science Center, Idaho Water Science Center

Human-associated indicator bacteria and human-specific viruses in surface water: a spatial assessment with implications on fate and transport 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...
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
By
Upper Midwest Water Science Center

Patterns of host-associated fecal indicators driven by hydrology, precipitation, and land use attributes in Great Lakes watersheds 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...
Authors
Deborah K. Dila, Steven R. Corsi, Peter L. Lenaker, Austin K. Baldwin, Melinda J. Bootsma, Sandra L. McLellan
By
Upper Midwest Water Science Center

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.

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