Dorothy J Merritts Harry W. & Mary B. Huffnagle Professor of Geosciences, Weis College House Don

Office: Hackman 121D

Phone: (717) 358-4398

Email: dorothy dot merritts at fandm dot edu

About Dorothy Merritts


Dorothy Merritts (B.Sc. Indiana University of Pennsylvania, M.Sc. Stanford University, Ph.D. University of Arizona) is a geologist with expertise in streams, rivers, and other landforms, and on the impact of geologic processes, climate change, and human activities on the form and history of Earth's surface.  Her primary research in the eastern United States is in the Appalachian mid-Atlantic region, where she is investigating the role of human activities in transforming the upland woodlands and valley bottom wetland meadows of Eastern North America to a predominantly agricultural and mixed-industrial/urban landscape since European settlement.  Associated with this work is developing new methods of wetland, floodplain, and stream restoration that rely upon geomorphic investigation. She uses lidar and other remote sensing data to map geomorphic evidence for continuous permafrost during the last glacial maximum period throughout Pennsylvania and Maryland.  In the western United States, she conducted research along the northern San Andreas Fault of coastal California for two decades; her international work focused on fault movements in South Korea, Indonesia, Australia, and Costa Rica. She is a professor in the Department of Earth and Environment at Franklin & Marshall College in Lancaster, Pennsylvania.  From 2004 to 2005 she was the Flora Stone Mather Visiting Distinguished Professor at Case Western Reserve University in Cleveland, Ohio.  From 2011 to 2012 she was the Alan Cox Visiting Professor at Stanford University.  She is the author of an introductory textbook in environmental geology, numerous scientific papers and edited book chapters, and contributing author to five National Research Council reports. She was elected as a member of the National Academy of Sciences in 2022.

Her full cirriculum vitae can be viewed HERE.


B.Sc. Indiana University of Pennsylvania

M.Sc. Stanford University

Ph.D. University of Arizona


Merritts, D. J. and Rahnis, M. A., 2022. Pleistocene periglacial processes and landforms, mid-Atlantic region, eastern United States, Volume 50, Annual Review of Earth and Planetary Sciences.

Phillips, C.B., Masteller, C.C., Slater, L.J., Dunne, K.B., Francalanci, S., Lanzoni, S., Merritts, D.J., Lajeunesse, E., and Jerolmack, D.J., 2022. Threshold constraints on the size, shape and stability of alluvial rivers. Nat Rev Earth Environ.

Gibbard, P., Walker, M., Bauer, A., Edgeworth, M., Edwards, L., Ellis, E., Finney, S., Gill, J.L., Maslin, M., Merritts, D. and Ruddiman, W., 2022. The Anthropocene as an Event, not an Epoch. Journal of Quaternary Science, 37(3), pp.395-399.

Gibbard PL, Bauer AM, Edgeworth M, Ruddiman WF, Gill JL, Merritts DJ, Finney SC, Edwards LE, Walker MJC, Maslin M, Ellis EC.  A practical solution: the Anthropocene is a geological event, not a formal epoch.  Episodes -0001;0:-.

Bauer, A.M., Edgeworth, M., Edwards, L.E., Ellis, E.C., Gibbard, P. and Merritts, D.J., 2021. Anthropocene: event or epoch? Nature, 597(7876), pp.332-332.

Lewis, E., Inamdar, S., Gold, A.J., Addy, K., Trammell, T.L., Merritts, D., Peipoch, M., Groffman, P.M., Hripto, J., Sherman, M. and Kan, J., 2021. Draining the landscape: How do nitrogen concentrations in riparian groundwater and stream water change following milldam removal? Journal of Geophysical Research: Biogeosciences, p.e2021JG006444.

Wohl, E., Castro, J., Cluer, B., Merritts, D., Powers, P., Staab, B. and Thorne, C., 2021. Rediscovering, Reevaluating, and Restoring Lost River-Wetland Corridors. Frontiers in Earth Science, 9, p.511.

Inamdar, S., Peipoch, M., Gold, A.J., Lewis, E., Hripto, J., Sherman, M., Addy, K., Merritts, D., Kan, J., Groffman, P.M. and Walter, R., 2021. Ghosts of landuse past: legacy effects of milldams for riparian nitrogen (N) processing and water quality functions. Environmental Research Letters, 16(3), p.035016.

National Academies of Sciences, Engineering, and Medicine, 2020. Review of the New York City Watershed Protection Program. National Academies Press.

Dow, S., Snyder, N.P., Ouimet, W.B., Martini, A.M., Yellen, B., Woodruff, J.D., Newton, R.M., Merritts, D.J. and Walter, R.C., 2020. Estimating the timescale of fluvial response to anthropogenic disturbance using two generations of dams on the South River, Massachusetts, USA. Earth Surface Processes and Landforms, 45(10), pp.2380-2393.

Fleming, P.M., Merritts, D.J. and Walter, R.C., 2019, Legacy sediment erosion hot spots: A cost-effective approach for targeting water quality improvements: Journal of Soil and Water Conservation, 74(4), pp.67A-73A.

Miller, A., M. Baker, K. Boomer, D. Merritts, K. Prestegaard, and S. Smith. 2019. Legacy Sediment, Riparian Corridors, and Total Maximum Daily Loads. STAC Publication Number 19- 001, Edgewater, MD. 64 pp.

Johnson, K.M., Snyder, N.P., Castle, S., Hopkins, A.J., Waltner, M., Merritts, D.J. and Walter, R.C., 2019. Legacy sediment storage in New England river valleys: Anthropogenic processes in a postglacial landscape. Geomorphology, 327, pp.417-437.

Moon, S., Merritts, D.J., Snyder, N.P., Bierman, P., Sanquini, A., Fosdick, J.C., and Hilley, G.E., 2018, Erosion of coastal drainages in the Mendocino Triple Junction region (MTJ), northern California: Earth and Planetary Science Letters, 502, pp.156-165.

Inamdar, S., Johnson, E., Rowland, R., Warner, D., Walter, R. and Merritts, D., 2017, Freeze–thaw processes and intense rainfall: the one-two punch for high sediment and nutrient loads from mid- Atlantic watersheds. Biogeochemistry.

Elliott, S.J., Grettenberger, C.L., Donovan, M.P., Wilf, P., Walter, R.C. and Merritts, D.J., 2016. Riparian and valley-margin hardwood species of pre-colonial Piedmont forests: A preliminary study of subfossil leaves from White Clay Creek, southeastern Pennsylvania, USA. Palaeontologia Electronica, 19 (1), pp.1-26.

Larsen, L., Hajek, E., Maher, K., Paola, C., Merritts, D., Bralower, T., Montanez, I., Wing, S., Snyder, N., Hochella, M., Kump, L. R., and Person, M., 2015, Taking the pulse of the Earth's surface systems: Eos, 96, doi:10.1029/2015EO040525. (

Pelletier, J. D., Brad Murray, A., Pierce, J. L., Bierman, P. R., Breshears, D. D., Crosby, B. T., Foufoula-Georgiou,E., Heimsath, A. M., Houser, C., Lancaster, N., Marani, M., Merritts, D. J., Moore, L. J., Pederson, J. L., Poulos, M. J., Rittenour, T. M., Rowland, J. C., Ruggiero, P., Ward, D. J., Wickert, A. D., & Yager, E. M., 2015, Forecasting the response of Earth's surface to future climatic and land‐use changes: A review of methods and research needs:  Earth's Future, v. 3, Issue 7, July 2015, pp. 220–251. Available at

Elliott, Sara J., Peter Wilf, Robert C. Walter, and Dorothy J. Merritts, 2013, Subfossil Leaves Reveal a New Upland Hardwood Component of the Pre-European Piedmont Landscape, Lancaster County, Pennsylvania: PLOS ONE 8, no. 11 (November 13, 2013): e79317. doi:10.1371/journal.pone.0079317. Available at  (C.f.,‎.)

Merritts, Dorothy, Rahnis, Michael, Walter, Robert, Hartranft, Jeff, Cox, Scott, Scheid, Chris*, Potter, Noel*, Jenschke, Matthew*, Reed, Austin*, Matuszewski, Derek*, Kratz, Laura*, Manion, Lauren*, Shilling, Andrea*, Datin, Katherine*, 2011 (in press), The rise and fall of Mid-Atlantic streams: Millpond sedimentation, milldam breaching, channel incision, and stream bank erosion:  Reviews in Engineering Geology, special issue on “The Challenges of Dam Removal and River Restorations”, editors Jerome V. DeGraff and James E. Evans.

Hartranft, Jeffrey, Merritts, Dorothy, Walter, Robert, Rahnis, Michael, 2011, The Big Spring Run restoration experiment:  Policy, geomorphology, and aquatic ecosystems in the Big Spring Run watershed, Lancaster County, PA:  Sustain: A Journal of Environmental and Sustainability Issues:  Issue 24, p. 24-30.

Merritts, Dorothy, Walter, Robert, Rahnis, Michael, Hartranft, Jeff, Cox, Scott, Gellis, Allen, Potter, Noel, Hilgartner, William, Langland, Michael, Manion, Lauren*, Lippincott, Caitlin*, Siddiqui, Sauleh*, Rehman, Zain*, Scheid, Chris*, Kratz, Laura*, Shilling, Andrea*, Jenschke, Matthew*, Reed, Austin*, Matuszewski, Derek*, Voli, Mark*, Datin, Katherine*, Ohlson, Erik*, Neugebauer, Ali*, Ahamed, Aakash*, Neal, Conor*, Winter, Allison*, and Becker, Steven*, 2011, Anthropocene streams and base-level controls from historic dams in the unglaciated mid-Atlantic region, USA:  Phil. Trans. R. Soc. A, v. 369, p. 1–34. (One contribution of 13 to a Theme Issue ‘The Anthropocene: a new epoch of geological time?’)

Merritts, Dorothy, Walter, Robert, and Rahnis, Michael, 2010, Water-powered Milling and Its Legacy as a Source of Suspended Sediment to the Susquehanna River and Chesapeake Bay:  Feature article in Susquehanna River Basin Commission Report State of the Susquehanna 2010:

Voli, Mark, Merritts, D., Walter, R., Ohlson, E., Datin, K., Rahnis, M., Kratz, L., Deng, W., Hilgartner, W., and Hartranft, J., 2009, Preliminary reconstruction of a Pre-European Settlement Valley Bottom Wetland, Southeastern Pennsylvania. Water Resources Impact, v. 11, no. 5, p. 11-13.

Litchfield, Nicola, Ota, Yoko, and Merritts, Dorothy, 2009, Tectonic Uplift and Subsidence (Chapter 7), in Volcanic and Tectonic Hazard Assessment for Nuclear Facilities:  Cambridge University Press, edited by Connor, C., Connor, L., and Chapman, N., p. 116-141.,+ota,+merritts&hl=en&sa

Walter, R.C. and Merritts, D.J., 2008, What to Do About Those Dammed Streams (Comment and Reply), Peter Wilcock and Walter/Merritts, Science, 321 (5891), 910-912 [DOI:10.1126/science.321.5891.910b]


Walter, R.C. and Merritts, D.J., 2008. Dammed You Say. Science Online:

Walter, Robert, and Merritts, Dorothy, 2008, Natural streams and the legacy of water-powered milling:  Science, v. 319, p. 299-304.

Annual Conference of Pennsylvania Field Geologists Field Guide, Mount Holly Springs breached mill-pond (Eaton-Dikeman mill), September 25, 2008.  [PDF, 2.4 MB]

Choi, S.-J., D. J. Merritts, and Y. Ota (2008), Elevations and ages of marine terraces and late Quaternary rock uplift in southeastern Korea, J. Geophys. Res., 113, B10403,

Wohl, Ellen, and Merritts, Dorothy, 2007, What is a natural river?  Geography Compass, v. 1, no. 4, p. 871-900, Blackwell Publishing, doi: 10.1111/j.1749-8198.2007.00049.x.

Merritts, Dorothy, 2007, Fluvial environments:  Terrace sequences: in Elias, Scott (ed.), Encyclopedia of Quaternary Science, p. 694-704. 

Thomas W. Gardner, John Webb, Aaron G. Davis, Elizabeth J. Cassell, Claudia Pezzia, Dorothy J. Merritts, and Barton Smith, 2006, Late Pleistocene landscape response to climate change: Eolian and alluvial fan deposition, Cape Liptrap, southeastern Victoria, Australia: Quaternary Research, v. 25, p. 1552-1569.

Griggs, Gary, Savoy, Lauret,, Runyan, Kiki, and Merritts, Dorothy, 2005, The Northern California Coast: Oregon Border to Point Delgada, Chapter 9 in The Changing Coast of California, edited by Gary Griggs and Kiki Runyan:  University of California Press.

Merritts, Dorothy, Savoy, Lauret, Griggs, Gary, Walter, Robert, 2005, The Northern Coast of California: Point Delgada to Point Arena, Chapter 10 in The Changing Coast of California, edited by Gary Griggs and Kiki Runyan:  University of California Press.

Savoy, Lauret, Merritts, Dorothy, Grove, Karen, and Walter, Robert, 2005, The Northern Coast of California: Point Arena to San Francisco, Chapter 11 in The Changing Coast of California, edited by Gary Griggs and Kiki Runyan:  University of California Press.

Snyder, Noah P., Whipple, Kelin X., Tucker, Greg E., and Merritts, Dorothy J., 2003, Channel response to tectonic forcing:  Field analysis of stream morphology and hydrology in the Mendocino triple junction region, northern California:  Geomorphology, v. 53, p. 97-127. 

Snyder, Noah P., Whipple, Kelin X., Tucker, Greg E., and Merritts, Dorothy J., 2003, Importance of a stochastic distribution of floods and erosion thresholds in the bedrock river incision problem:  Journal of Geophysical Research, v. 108, B2, p. 2117-2132.

Snyder, Noah P., Whipple, Kelin X., Tucker, Greg E., and Merritts, Dorothy J., 2002, Interactions between onshore bedrock-channel incision and nearshore wave-base erosion forced by eustasty and tectonics:  Basin Research, v. 14, p. 105-127.

Gardner, Thomas, Marshall, Jeffrey, Merritts, Dorothy, Bee, Bhavani, Burgette, Reed, Burton, Emily, Cooke, Jennifer, Kehrwald, Natalie, Protti, Marino, Fisher, Donald, and Sak, Peter, 2001, Holocene forearc block rotation in response to seamount subduction, southeastern Peninsula de Nicoya, Costa Rica:  Geology (Boulder), v. 29, no. 2, p. 151-154.

Merritts, Dorothy J., Bodin, Paul, Beutner, Edward, Prentice, Carol S., and Muller, Jordan, 2000, Active surface deformation in the Mendocino triple junction process zone:  in Bokelman, Gotz, and Kovach, Robert L. (editors), Proceedings of the 3rd Conference on Tectonic Problems of the San Andreas Fault System, Stanford University Publications/Geological Sciences Volume XXI, September, 2000, pages 128-143. See

Merritts, Dorothy, 2000, The effects of variable river flow on human communities:  In Wohl, Ellen E. (Editor), Inland Flood Hazards:  Human, Riparian, and Aquatic Communities, Cambridge University Press, p. 271-290.

Prentice, C.S. Langridge, R., and Merritts, D J., 2000, Paleoseismic and Quaternary tectonic studies of the San Andreas fault from Shelter Cove to Fort Ross, in: Bokelmann, G. and Kovach, R.L., eds.: Proceedings of the Third Conference on Tectonic Problems of the San Andreas System, Stanford University Publications, p.349-350.

Snyder, Noah P., Whipple, Kelin X., Tucker, Greg E., and Merritts, Dorothy J., 2000, Landscape response to tectonic forcing:  Digital elevation model analysis of stream profiles in the Mendocino triple junction region, northern California:  Geological Society of America Bulletin, v. 112, no. 8, pl. 1250-1263.

Prentice, Carol S., Merritts, Dorothy J., Beutner, Edward, Bodin, Paul, Schill, Allison, and Muller, Jordan, 1999,  The northern San Andreas fault near Shelter Cove, California.  Geological Society of America Bulletin, v. 111, n. 4, p. 512-523.

Pazzaglia, Frank J., Gardner, Thomas W., and Merritts, Dorothy J., 1998, Bedrock fluvial incision and longitudinal profile development over geologic time scales determined by fluvial terraces:  in Rivers Over Rock:  Fluvial Processes in Bedrock Channels, edited by Ellen Wohl, American Geophysical Union Geophysical Mongraph Series, no. 107, p. 207-235.

Merritts, Dorothy, Eby, Rebecca, Harris, Ron, Edwards, R. Lawrence, and Cheng, Hai, 1998, Variable rates of late Quaternary surface uplift along the Banda Arc-Australian Plate collision zone: In Stewart, I. S., and Vita-Finzi, C. (editors), Coastal Tectonics.  Geological Society, London, Special Publications, vol. 146, p. 213-224.

Merritts, Dorothy, 1996, The Mendocino triple junction:  Active faults, paleoseismicity, and causes of rapid uplift: Journal of Geophysical Research (special issue on Paleoseismology), v. 99, no. B7, p. 14,031-14,050.

Merritts, Dorothy, and Brustolon, Amy, 1995, The Mendocino triple junction:  Active faults, paleoseismicity, and causes of rapid uplift:  USGS Open-File Report on International Lithosphere Program-U. S. Geological Survey Workshop on Paleoseismology.

Merritts, Dorothy, and Tim Hesterberg, August, 1994, Stream networks and long-term surface uplift, New Madrid seismic zone:  Statistical and topographic modeling: Science, v. 265, p. 1081-1084.

Merritts, Dorothy, and Ellis, Michael, 1994, Introduction to Special Issue on Tectonics and Topography, in Ellis, M. and Merritts, D., editors, Tectonics and Topography, Special Section Part I, Journal of Geophysical Research, v. 99, no. B6, p. 12,135-12,141.

Merritts, Dorothy, Vincent, Kirk, and Wohl, Ellen, July, 1994, Long river profiles, tectonism, and eustasy:  A guide to interpreting fluvial terraces:  in Ellis, M. and Merritts, D., editors, Tectonics and Topography, Special Section Part II, Journal of Geophysical Research, v. 99, no. B7, p. 14,031-14,050.

Chadwick, Oliver, Kelly, Eugene, Merritts, Dorothy, and Amundson, R. G., 1994, Carbon dioxide consumption during soil development:  Biogeochemistry, v.24, no. 3, p. 115-128. 

Merritts, Dorothy J., Chadwick, Oliver A., Hendricks, David M., Brimhall, George H., and Lewis, Christopher J., 1992, The mass balance of soil evolution on late Quaternary marine terraces, northern California:  Geological Society of America Bulletin, v. 104, p. 1476-1499.

Merritts, D. J., Chadwick, O. A., and Hendricks, D. M., 1991, Rates and processes of soil evolution on uplifted marine terraces, northern California:  Geoderma, v. 51, p. 241-275.

Merritts, Dorothy, and Vincent, Kirk R., 1989, Geomorphic response of coastal streams to low, intermediate, and high rates of uplift, Mendocino triple junction region, northern California:  Geological Society of America Bulletin, v. 101, p. 1373-1388.

Merritts, D.J., and Bull, W. B., 1989, Interpreting Quaternary uplift rates at the Mendocino triple junction, northern California, from uplifted marine terraces:  Geology, v. 17, p. 1020-1024.

Course Information

Geomorphology, hydrology, water resources, and environmental geology.

Grants, Professional Service, & Awards


Elected to the National Academy of Sciences, 2022

Geological Society of America Distinguished Career Award, Quaternary Geology and Geomorphology Division, 2022

Vice-Chair, National Academies of Sciences, Engineering, and Medicine’s Committee on the Review of the New York City Watershed Protection Program, 2018-2020 (lead author Chapter 6, Stream Management) 

Chair, National Academies/National Research Council Committee on Landscape Conservation Cooperatives, 2014-2016 

Committee Member, National Academies/National Research Council Board on Earth Sciences and Resources, 2013-2020

NSF-Sponsored Workshop Participant:  Research Infrastructure for Surface Earth Processes, October, 2014.

NSF-Funded Workshop Participant:  Prediction of Landscape Response to Climatic and Land-Use Changes (Biosphere II, Tucson, AZ), September 2013

Co-organizer and participant, EPA Region 3 Legacy Sediment Workshop at Franklin and Marshall College in Lancaster, PA. May 9-10, 2012

NSF-Funded SEES Workshop Co-Leader: Research in Landscape Sustainability: Earth-surface processes in the SEES (Science, Engineering, and Education for Sustainability) context; co-leader with C. Paola (U Minnesota), 2011.

Cox Visiting Professor, Stanford University, School of Earth and Environmental Sciences, 2011-2012.

Geological Society of America, Kirk Bryan Award (Best Paper) to Walter, Robert C., and Dorothy Merritts, 2011, for "Natural streams and the legacy of water-powered mills", published in Science, 2008, v. 319, p. 299-304.  Citation and responses at

Bradley Dewey Award for Outstanding Scholarship, Franklin and Marshall College, 2010

Chair, National Academy of Sciences Committee on Challenges and Opportunities in Earth Surface Processes, 2007-2010. 

Workshop leader and organizer, New tools in high-resolution topographic analysis with lidar, University of Colorado, Boulder, June 2010 (National Science Foundation funding)

Workshop leader and organizer, High-resolution topographic analysis with lidar, University of Colorado, Boulder, June 2008 (National Science Foundation funding)

Presenter, William Morris Davis lecture (2nd annual), Boston College, 2009:  “An unnatural river runs through it.”  Audio and slides available at

Senate Resolution 283 (2008) The State of Pennsylvania Senate Resolution 283: “Whereas, Professor Walter’s and Professor Merritts” scientific skills, professionalism and ability to communicate this new information have provided invaluable assistance to this Commonwealth and its partners in understanding stream dynamics and integrating this knowledge into restoration efforts of the Chesapeake Bay and its tributaries…”.

Association of Women Geoscientists’ Outstanding Educator award, 2006.  

Flora Stone Mather Distinguished Professor, Case Western Reserve University, 2004-2005

Distinguished lecturer, Vassar College, October, 1997

Dissertation fellowship, National Science Foundation, 1983-1987

  1. A. Tarr Award for Outstanding Senior Graduate, 1980


Recent Grants

Snyder, Noah, Merritts, Dorothy, and Walter, Robert, 2015-2017, Anthropocene sedimentation in valley bottoms a geologically significant event?, National Science Foundation EAR Geomorphology and Land Use Dynamics, Award Number 1451586.

Walter, Robert, and Merritts, Dorothy, 2012-2014, Collaborative Proposal with A. Gellis and M. Langland of USGS, and L. Larsen of UC Berkeley, Landscape evolution and sediment-nutrient fluxes in a wetland-stream restoration experiment, National Science Foundation EAR Geomorphology and Land Use Dynamics, Award Number 1226972.

Walter, Robert, and Merritts, Dorothy, 2010-2015, Floodplain restoration and Sediment/Nutrient Load Reductions, US EPA & PA Department of Environmental Protection.

Merritts, Dorothy, Walter, Robert, Mertzman, Stan, William, Chris, and Yoder, Claude (co-PIs), 2009-2011, National Science Foundation-Major Research Instrumentation Grant for the upgrade of existing XRF facilities and to purchase new analytical instruments, including XRD spectrometer, two gamma ray spectrometers, a laser particle analyzer, an x-ray particle analyzer, and RTK GPS instrument.

Walter, Robert, and Merritts, Dorothy (with M. Langland, D. Galeone, and A. Gellis, USGS), 2008-2010, Floodplain restoration and Sediment/Nutrient Load Reductions, PA Department of Environmental Protection.

Merritts, Dorothy, and Walter, Robert, 2006-2008, Statewide (PA) stream bank erosion and nutrient loads from legacy sediments:  PA Department of Environmental Protection (PA).