Water-Quality Trends From Lake Cores Active
Sediment cores let us look back in time at the contaminant history of a watershed. Learn about what lake and reservoir sediment cores tell us about trends in metals, organochlorine pesticides, polycyclic aromatic hydrocarbons, and other sediment-related contaminants.
Water-quality trends can provide an assessment of the effectiveness of regulatory actions aimed at improving water quality, a warning of water-quality degradation, and an improved understanding of how human activities affect water quality.
Sediment cores—long tubes of mud—are collected from a lake or reservoir and sliced into thin intervals. Each slice represents an interval of time. By analyzing the sediments in each slice for the contaminants of interest, changes in the occurrence of contaminants and their use in the watershed can be reconstructed. The approximate date corresponding to deposition of the sediment in each slice is determined by analysis of radionuclides (cesium-137 and lead-210).
USGS studies of reconstructed trends in metals and hydrophobic organic contaminants have shed light on the effectiveness of restrictions on the use of leaded gasoline, DDT, and PCBs, and the effectiveness of the Clean Air Act in reducing concentrations of some heavy metals. The studies also have identified some contaminants, like polycyclic aromatic hydrocarbons (PAHs), whose concentrations are increasing in urban areas, spurring efforts to identify the source or sources of these upward trends.
Find out more about coal-tar-based sealcoat, a potent source of PAHs to lake and streambed sediment, and related environmental health issues.
NATIONAL SUMMARIES
- Increased mercury fallout near major U.S. cities (Environ. Pollution, 2012)
- Coal-tar sealcoat largest PAH source to U.S. lakes (Sci. Total Env., 2010)
- PAH in coal tar sealcoat a national problem (Env. Sci. & Tech., 2009)
- National-scale trends in organics (Env. Sci. & Tech., 2005)
- National-scale trends in metals (Env. Tox. & Chem., 2006) associated Data Report
- Methods and age dating of cores (USGS SIR 2004-5184)
- Urban trends in PAHs (Env. Sci. & Tech., 2000)
- Rates of decrease in DDT and PCBs (Env. Sci. & Tech., 1998)
- Trends in organochlorine compounds (Env. Sci. & Tech., 1997)
TOPICAL FINDINGS
- Evaluating mercury and 210Pb atmospheric fallout and focusing to lakes (Env. Sci. & Tech., 2009)
- Effects of Hurricanes Katrina and Rita on Lake Pontchartrain sediments (Env. Sci. & Tech., 2006)
- Parking lot sealcoat: an urban source of PAHs (Env. Sci. & Tech., 2005) associated fact sheet, data report
- Chemical response to urbanization, New England, USA (Chalmers et al. 2007)
- Contaminant trends in the Mississippi River Basin (Van Metre and Horowitz 2013)
- Reservoir cores versus stream suspended sediments (Env. Sci. & Tech., 2004)
- Monitoring suspended sediment chemistry (Arch. Env. Contam. & Tox., 2003)
- Metal diagenesis in reservoir cores (J. Paleolimnology, 2000)
LOCAL RESULTS
- PAHs decline after ban on coal-tar sealcoat, Austin, TX (Env. Sci. Technol., 2014)
- Chemical response of particle-associated contaminants in aquatic sediments to urbanization in New England (Contam. Hydro., 2007)
- Lead and zinc in greater Atlanta, Georgia (Env. Sci. & Tech., 2000)
- Trends in White Rock Lake, Texas (J. Paleolimnology, 1997)
Read about additional science related to sediment-associated contaminants and water-quality trends by following the links to web pages below.
Learn more about water quality trends as recorded in sediment cores at the publications below.
Trends in hydrophobic organic contaminants in urban and reference lake sediments across the United States, 1970-2001
Major and trace elements in 35 lake and reservoir sediment cores from across the United States, 1994-2001
Trends in metals in urban and reference lake sediments across the United States, 1970 to 2001
Effects of hurricanes Katrina and Rita on the chemistry of bottom sediments in Lake Pontchartrain, Louisiana, USA
Trends in hydrophobic organic contaminants in urban and reference lake sediments across the United States, 1970-2001
Parking lot sealcoat: a major source of polycyclic aromatic hydrocarbons (PAHs) in urban and suburban environments
Parking lot sealcoat: An unrecognized source of urban polycyclic aromatic hydrocarbons
Tire-wear particles as a source of zinc to the environment
Concentrations of polycyclic aromatic hydrocarbons (PAHs) and major and trace elements in simulated rainfall runoff from parking lots, Austin, Texas, 2003
Contaminant trends in reservoir sediment cores as records of influent stream quality
Collection, analysis, and age-dating of sediment cores from 56 U.S. lakes and reservoirs sampled by the U.S. Geological Survey, 1992-2001
Trends in chemical concentration in sediment cores from three lakes in New Jersey and one lake on Long Island, New York
A simplified approach for monitoring hydrophobic organic contaminants associated with suspended sediment: Methodology and applications
- Overview
Sediment cores let us look back in time at the contaminant history of a watershed. Learn about what lake and reservoir sediment cores tell us about trends in metals, organochlorine pesticides, polycyclic aromatic hydrocarbons, and other sediment-related contaminants.
Water-quality trends can provide an assessment of the effectiveness of regulatory actions aimed at improving water quality, a warning of water-quality degradation, and an improved understanding of how human activities affect water quality.
Sediment cores—long tubes of mud—are collected from a lake or reservoir and sliced into thin intervals. Each slice represents an interval of time. By analyzing the sediments in each slice for the contaminants of interest, changes in the occurrence of contaminants and their use in the watershed can be reconstructed. The approximate date corresponding to deposition of the sediment in each slice is determined by analysis of radionuclides (cesium-137 and lead-210).
USGS studies of reconstructed trends in metals and hydrophobic organic contaminants have shed light on the effectiveness of restrictions on the use of leaded gasoline, DDT, and PCBs, and the effectiveness of the Clean Air Act in reducing concentrations of some heavy metals. The studies also have identified some contaminants, like polycyclic aromatic hydrocarbons (PAHs), whose concentrations are increasing in urban areas, spurring efforts to identify the source or sources of these upward trends.
Find out more about coal-tar-based sealcoat, a potent source of PAHs to lake and streambed sediment, and related environmental health issues.
NATIONAL SUMMARIES
- Increased mercury fallout near major U.S. cities (Environ. Pollution, 2012)
- Coal-tar sealcoat largest PAH source to U.S. lakes (Sci. Total Env., 2010)
- PAH in coal tar sealcoat a national problem (Env. Sci. & Tech., 2009)
- National-scale trends in organics (Env. Sci. & Tech., 2005)
- National-scale trends in metals (Env. Tox. & Chem., 2006) associated Data Report
- Methods and age dating of cores (USGS SIR 2004-5184)
- Urban trends in PAHs (Env. Sci. & Tech., 2000)
- Rates of decrease in DDT and PCBs (Env. Sci. & Tech., 1998)
- Trends in organochlorine compounds (Env. Sci. & Tech., 1997)
TOPICAL FINDINGS
- Evaluating mercury and 210Pb atmospheric fallout and focusing to lakes (Env. Sci. & Tech., 2009)
- Effects of Hurricanes Katrina and Rita on Lake Pontchartrain sediments (Env. Sci. & Tech., 2006)
- Parking lot sealcoat: an urban source of PAHs (Env. Sci. & Tech., 2005) associated fact sheet, data report
- Chemical response to urbanization, New England, USA (Chalmers et al. 2007)
- Contaminant trends in the Mississippi River Basin (Van Metre and Horowitz 2013)
- Reservoir cores versus stream suspended sediments (Env. Sci. & Tech., 2004)
- Monitoring suspended sediment chemistry (Arch. Env. Contam. & Tox., 2003)
- Metal diagenesis in reservoir cores (J. Paleolimnology, 2000)
LOCAL RESULTS
- PAHs decline after ban on coal-tar sealcoat, Austin, TX (Env. Sci. Technol., 2014)
- Chemical response of particle-associated contaminants in aquatic sediments to urbanization in New England (Contam. Hydro., 2007)
- Lead and zinc in greater Atlanta, Georgia (Env. Sci. & Tech., 2000)
- Trends in White Rock Lake, Texas (J. Paleolimnology, 1997)
- Science
Read about additional science related to sediment-associated contaminants and water-quality trends by following the links to web pages below.
- Publications
Learn more about water quality trends as recorded in sediment cores at the publications below.
Trends in hydrophobic organic contaminants in urban and reference lake sediments across the United States, 1970-2001
A shift in national policy toward stronger environmental protection began in the United States in about 1970. Conversely, urban land use, population, energy consumption, and vehicle use have increased greatly since then. To assess the effects of these changes on water quality, the U.S. Geological Survey used sediment cores to reconstruct water-quality histories for38 urban and reference lakes acroAuthorsP. C. Van Metre, B.J. MahlerFilter Total Items: 42Major and trace elements in 35 lake and reservoir sediment cores from across the United States, 1994-2001
This report presents data on major and trace element concentrations in sediment cores collected from 35 lakes and reservoirs during 1994-2001. The lakes and reservoirs are located in or near 18 major urban areas across the United States and provide a geographically diverse coverage of urban land use for the country as well as some reference settings. Vertical intervals of the cores were analyzed fAuthorsPeter C. Van Metre, Barbara Mahler, Jennifer T. Wilson, Edward CallenderTrends in metals in urban and reference lake sediments across the United States, 1970 to 2001
Trends in metals concentrations in sediment cores from 35 reservoirs and lakes in urban and reference settings were analyzed to determine the effects of three decades of legislation, regulation, and changing demographics and industrial practices in the United States on concentrations of metals in the environment. Decreasing trends outnumber increasing trends for all seven metals analyzed (Cd, Cr,AuthorsB.J. Mahler, P. C. Van Metre, E. CallenderEffects of hurricanes Katrina and Rita on the chemistry of bottom sediments in Lake Pontchartrain, Louisiana, USA
The effects of Hurricanes Katrina and Rita and the subsequent unwatering of New Orleans, Louisiana, on the sediment chemistry of Lake Pontchartrain were evaluated by chemical analysis of samples of street mud and suspended and bottom sediments. The highest concentrations of urban-related elements and compounds (e.g., Pb, Zn, polycyclic aromatic hydrocarbons, and chlordane) in bottom sediments exceAuthorsP. C. Van Metre, A. J. Horowitz, B.J. Mahler, W.T. Foreman, C. C. Fuller, M.R. Burkhardt, K. A. Elrick, E. T. Furlong, S. C. Skrobialowski, J.J. Smith, J.T. Wilson, S.D. ZauggTrends in hydrophobic organic contaminants in urban and reference lake sediments across the United States, 1970-2001
A shift in national policy toward stronger environmental protection began in the United States in about 1970. Conversely, urban land use, population, energy consumption, and vehicle use have increased greatly since then. To assess the effects of these changes on water quality, the U.S. Geological Survey used sediment cores to reconstruct water-quality histories for38 urban and reference lakes acroAuthorsP. C. Van Metre, B.J. MahlerParking lot sealcoat: a major source of polycyclic aromatic hydrocarbons (PAHs) in urban and suburban environments
Collaborative studies by the City of Austin and the U. S. Geological Survey (USGS) have identified coal-tar based sealcoat—the black, shiny emulsion painted or sprayed on asphalt pavement such as parking lots—as a major and previously unrecognized source of polycyclic aromatic hydrocarbon (PAH) contamination. Several PAHs are suspected human carcinogens and are toxic to aquatic life. Studies in AuAuthorsPeter C. Van Metre, Barbara Mahler, Mateo Scoggins, Pixie A. HamiltonParking lot sealcoat: An unrecognized source of urban polycyclic aromatic hydrocarbons
Polycyclic aromatic hydrocarbons (PAHs) are a ubiquitous contaminant in urban environments. Although numerous sources of PAHs to urban runoff have been identified, their relative importance remains uncertain. We show that a previously unidentified source of urban PAHs, parking lot sealcoat, may dominate loading of PAHs to urban water bodies in the United States. Particles in runoff from parking loAuthorsB.J. Mahler, P. C. Van Metre, T. J. Bashara, J.T. Wilson, D. A. JohnsTire-wear particles as a source of zinc to the environment
Tire-tread material has a zinc (Zn) content of about 1 wt %. The quantity of tread material lost to road surfaces by abrasion has not been well characterized. Two approaches were used to assess the magnitude of this nonpoint source of Zn in the U.S. for the period 1936−1999. In the first approach, tread-wear rates from the automotive engineering literature were used in conjunction with vehicle disAuthorsT.B. Councell, K.U. Duckenfield, E. R. Landa, E. CallenderConcentrations of polycyclic aromatic hydrocarbons (PAHs) and major and trace elements in simulated rainfall runoff from parking lots, Austin, Texas, 2003
Samples of creek bed sediment collected near seal-coated parking lots in Austin, Texas, by the City of Austin during 2001–02 had unusually elevated concentrations of polycyclic aromatic hydrocarbons (PAHs). To investigate the possibility that PAHs from seal-coated parking lots might be transported to urban creeks, the U.S. Geological Survey, in cooperation with the City of Austin, sampled runoff aAuthorsBarbara Mahler, Peter C. Van Metre, Jennifer T. WilsonContaminant trends in reservoir sediment cores as records of influent stream quality
When reconstructing water-quality histories from lake and reservoir cores, it is sometimes assumed that the chemical signatures in the cores reflect historical water quality in the influent streams. To investigate this assumption, concentrations of metals, PAHs, and organochlorine compounds in sediment cores were compared to those associated with an influent-stream suspended sediment for three resAuthorsP. C. Van Metre, B.J. MahlerCollection, analysis, and age-dating of sediment cores from 56 U.S. lakes and reservoirs sampled by the U.S. Geological Survey, 1992-2001
The U.S. Geological Survey Reconstructed Trends National Synthesis study collected sediment cores from 56 lakes and reservoirs between 1992 and 2001 across the United States. Most of the sampling was conducted as part of the National Water-Quality Assessment (NAWQA) Program. The primary objective of the study was to determine trends in particle-associated contaminants in response to urbanization;AuthorsPeter Van Metre, Jennifer T. Wilson, Christopher C. Fuller, Edward Callender, Barbara MahlerTrends in chemical concentration in sediment cores from three lakes in New Jersey and one lake on Long Island, New York
Sediment cores were extracted from three lakes in northeastern New Jersey and one lake on western Long Island, New York, as part of the U.S. Geological Survey National Water-Quality Assessment Program. Sediment layers were dated by use of cesium-137 (137Cs), copper, lead, or dichlorodiphenyl-trichloroethane (DDT) profiles. Sediment layers were analyzed for seven selected trace elements, includingAuthorsGary R. Long, Edward C. Callender, Mark A. Ayers, Peter C. Van MetreA simplified approach for monitoring hydrophobic organic contaminants associated with suspended sediment: Methodology and applications
Hydrophobic organic contaminants, although frequently detected in bed sediment and in aquatic biota, are rarely detected in whole-water samples, complicating determination of their occurrence, load, and source. A better approach for the investigation of hydrophobic organic contaminants is the direct analysis of sediment in suspension, but procedures for doing so are expensive and cumbersome. We deAuthorsB.J. Mahler, P. C. Van Metre