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bio image of Barbara  Mahler

Barbara Mahler

Research Hydrologist

Contact Info

Short Biography

Barbara grew up in northern California, where she learned to appreciate the value of water.  She received a B. Mus. in performance at Boston University; in 1986 she moved to Austin, Texas.  Combining her interest in water, mathematics, and the outdoors, she enrolled at the University of Texas and received her Masters and Ph.D. degrees in Geology, with an emphasis on karst hydrology.  Her principal research interests are water quality of karst systems and source and fate of contaminated sediment.

Barbara has Masters and doctoral degrees in Geology from the University of Texas, where she studied with Dr. Philip Bennett.  The emphasis of her graduate research was the geochemistry of karst aquifers.  Her doctoral research focused on sediment transport through karst aquifers and its potential to serve as a vector for contaminant transport.  After completing her Ph.D. in 1997, she spent 1 year as an NSF/NATO International Postdoc in Montpellier, France, studying transport of sediment and bacteria in karst. 


She began her career with the USGS (Texas Water Science Center) in 1998, where she is a Research Hydrologist.  She is part of the Contaminant Trends in Lake Sediments (CTLS) team, which uses cores of sediments from lakes to reconstruct the contaminant histories of watersheds.  The CTLS has identified nation-wide patterns of trends in metals and organic contaminants, including lead, DDT, and PAHs.  Barbara’s associated research with the CTLS has included identification and evaluation of contaminant sources and processes, including rooftop runoff, suspended sediment in streams, contaminated runoff from parking lots, and house dust.  The CTLS has been instrumental in identifying and quantifying the importance of coal-tar-based parking lot sealcoat as a source of PAHs at the national scale. 


In addition to her participation in the CTLS, Barbara continues her research on karst, with active projects in France and Texas, notably in the Barton Springs segment of the Edwards aquifer.  She helped redesign and update the USGS karst web page (  She is an Associate Editor for the Journal of Hydrology, and a member of the IAH Karst Hydrogeology Commission.  Her publications in the field of karst have included analysis of pesticide breakthrough curves in spring flow, use of nitrate as a tracer of recent recharge, and use of principal components analysis to investigate nutrient dynamics in karst.


Barbara is a Research Fellow at the University of Texas Jackson School of Geosciences.  She regularly serves on the committees of Masters and Ph.D. students, and on occasion teaches courses and lectures at the University.  She has supervised a number of student interns at the USGS.  She continues her collaborations with French scientists, notably Dr. Nicolas Massei.  In 2006 she spent a year in Rouen, and recently spent a month in Lyon working with the French environmental agency IRSTEA.  She is a regular reviewer for numerous scientific journals, including Journal of Hydrology, Hydrogeology Journal, Environmental Science and Technology, and Journal of Contaminant Hydrology.

Download CV


Van Metre, P.C., Majewski, M.S., Mahler, B.J., Foreman, W.T., Braun, C.L., Wilson, J.T., and Burbank, T.L. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement. Chemosphere, 88(1):1-7. [Link]

Desmet, M., Mourier, B., Mahler, B.J., Van Metre, P., Roux, G., Persat, H., Lefèvre, Il, Peretti, A., Chapron, E., Simmonneau, A., Miège, C., and Babut, M. Spatial and temporal trends in PCBs in sediment along the lower Rhône River, France. Science of the Total Environment, 433:189-197.

Yang, Y., Van Metre, P.C., Mahler, B.J., Wilson, J.T., Ligouis, B., Razzaque, M., Schaeffer, C., and Werth, C. The influence of coal-tar sealcoat and other carbonaceous materials on polycyclic aromatic hydrocarbon loading in an urban watershed. Environmental Science and Technology, 44(4): 1217-1223. [Link]

Van Metre, P.C., and Mahler, B.J. Contribution of PAHs from coal-tar pavement sealcoat and other sources to 40 U.S. Lakes. Science of the Total Environment, 409: 334-344. [Link]

Yang, Y., Mahler, B.J., Van Metre, P.C., Ligouis, B., and Werth, C.J. Potential contributions of asphalt and coal tar to black carbon quantification in urban dust, soils, and sediment. Geochemica et Cosmochimica Acta, 74(23):6830-6840.

Mahler, B.J., Van Metre, P.C., Zaugg, S.D., Wilson, J.T., Musgrove, M., and Burkhardt, M.D. Fipronil and its degradates in indoor and outdoor dust. Environmental Science and Technology, 43: 5665-5670. [Link]

Van Metre, P.C., Mahler, B.J., and Wilson, J.T. 2009. PAHs underfoot: Contaminated dust from sealcoated pavement. Environ. Sci. Technol., 43:20-25. [Download File]

Mahler, B.J., Valdes, D., Massei, N., and Musgrove, M. 2008. Nutrient dynamics as indicators of karst processes: Comparison of the Chalk aquifer (Normandy, France) and the Edwards aquifer (Texas, U.S.A.). J. Contam. Hydrol., 98: 36-49.

Garner, B.D., and Mahler, B.J., 2007, Relation of specific conductance in ground water to intersection of flow paths by wells, and associated major ion and nitrate geochemistry, Barton Springs segment of the Edwards aquifer, Austin, Texas, 1978–2003: U.S. Geological Survey Scientific Investigations Report 2007–5002, 39 p., 5 appendixes. [Link]

Mahler, B.J., and Massei, N., 2007, Anthropogenic contaminants as tracers in an urbanizing karst aquifer. J. Cont. Hydrol., 91: 81-106.

Mahler, B.J., Garner, B.D., Musgrove, M., Guilfoyle, A.L., and Rao, M.V., 2006, Recent (2003–05) water quality of Barton Springs, Austin, Texas, with emphasis on factors affecting variability: U.S. Geological Survey ScientificInvestigations Report 2006–5299, 83 p., 5 appendixes. [Link]

Mahler, B. J.; Van Metre, P. C.; Wilson, J. T.; Guilfoyle, A. L.; Sunvison, M. W., 2006. Concentrations, Loads, and Yields of Particle-Associated Contaminants in Urban Creeks, Austin, Texas, 1999-2004. Geological Survey (U.S.) Scientific Investigations Report 2006-5262, viii, 107 p. [Link]

Mahler, B.J., Van Metre, P.C., and Callender, E. 2006. Trends in metals in urban and reference lake sediments across the United States, 1975-2001.Environ. Toxicol. Chem., 25: 1698-1709. [Download File]

Van Metre, Peter C.; Mahler, Barbara J.; Scoggins, Mateo; Hamilton, Pixie A., 2005. Parking lot sealcoat: a major source of polycyclic aromatic hydrocarbons (PAHs) in urban and suburban environments. Fact Sheet 2005-3147, 4 p. [Link]

Mahler, B.J., Van Metre, P.C., Bashara, T.J., Wilson, J.T., and Johns, D.A. 2005. Parking lot sealcoat: An unrecognized source of urban PAH. Environ. Sci. Technol., 39: 5560-5566.

Van Metre, P.C. and Mahler, B.J. 2005. Trends in hydrophobic organic contaminants in urban and reference lake sediments across the United States, 1970-2001. Environ. Sci. Technol., 39: 5567-5574. [Download File]

Van Metre, P.C., and Mahler, B.J. 2004. Contaminant trends in reservoir sediment cores as records of influent stream quality. Environ. Sci. Technol. 38: 2978-2986. [Download File]

Van Metre, P.C., and Mahler, B.J. 2003. The contribution of particles washed from rooftops to contaminant loading to urban streams. Chemosphere, 52: 1727-1741. [Download File]

Van Metre, P.C., Mahler, B.J., and Furlong, E.T. 2000. Urban sprawl leaves its PAH signature. Environ. Sci. Technol., 34: 4064-4070. [Download File]

Mahler, B.J., and Lynch, F.L. 1999. Muddy waters: Temporal variation in sediment discharging from a karst spring. J. Hydrol., 214: 165-178.

Mahler, B.J., Lynch, F.L., Bennett, P.C. 1998. Mobile sediment in an urbanizing karst aquifer: implications for contaminant transport. Environ. Geol., 39:25-39.


My Science Topics

Science Topic
Environmental Issuescontamination and pollution
Environmental Issuesground-water quality
Environmental Issueshuman impacts
Environmental Issuesland use
Environmental Issuesland use change
Environmental Issuesnonpoint-source pollution
Environmental Issuespesticides and herbicides
Environmental Issuespharmaceuticals
Environmental Issuessurface water quality
Environmental Issueswater quality

Sediment geochemistry, karst aquifers

Image of Current Focus for Sediment geochemistry, karst aquifers

Reconstruction of contaminant histories using lake cores; identification and evaluation of contaminant sources; sources and fate of PAHs (including parking lot sealcoat).

Karst water quality; use of aqueous geochemistry to understand karst systems; relations between recharge and spring discharge.

Contact Information

Barbara Mahler
1505 Ferguson Lane
Austin, TX 78754
512-927-3590 - Fax
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