Photo of Alfonso Mejia

Alfonso Mejia

Associate Professor


  • Civil and Environmental Engineering

215B Sackett Building


Personal or Departmental Website

Research Areas:

Water Resources Engineering

Interest Areas:

Hydrology, floods and droughts, hydrometeorology, urban-water systems, water resources sustainability, ecohydrology




  • BS, Civil and Environmental Engineering, University of Maryland, 1999
  • MS, Civil and Environmental Engineering, Colorado State University, 2006
  • Ph D, Civil and Environmental Engineering, University of Maryland, 2009


Journal Articles

  • P Sanzana, J Gironas, I Braud, N Hitschfeld, F Branger, F Rodriguez, M Fuamba, J Romero, X Vargas, J F Munoz, S Vicuna and A Mejia, 2019, "Decomposition of 2D polygons and its effect in hydrological models", Journal of Hydroinformatics, 21, (1), pp. 104-122
  • C Ahams, Willa Paterson, S Garcia, R Rushforth, B Ruddell and A Mejia, 2017, "Water footprint of 65 mid- to large-sized U.S. cities and their metropolitan areas", Journal of the American Water Resources Association, 53, (5), pp. 1147-1163
  • T Jovanovic, S García, H Gall and A Mejia, 2017, "Complexity as a streamflow metric of hydrologic alteration", Stochastic Environmental Research and Risk Assessment, 31, (8), pp. 2107–2119
  • H. Kreibich, T. Krueger, A. Van Loon, A. Mejia, J. Liu, H. McMillan and A. Castellarin, 2017, "Scientific debate of Panta Rhei research – how to advance our knowledge of changes in hydrology and society?", Hydrological Sciences Journal, 62, (3), pp. 331-333
  • S. Sharma, R. Siddique, N. Balderas, Jose D Fuentes, Seann Reed, Peter Ahnert, Robert Shedd, Brian Astifan, Reggina Cabrera, Arlene Laing, Mark Klein and A Mejia, 2017, "Eastern U.S. verification of precipitation forecasts", Weather and Forecasting, 32, (1), pp. 117–139
  • R. Siddique and A. Mejia, 2017, "Ensemble streamflow forecasting across the U.S. middle Atlantic region", Journal of Hydrometeorology, 18, (7), pp. 1905–1928
  • P. Sanzana, J. Gironas, I Braud, F Branger, F Rodriguez, X Vargas, N Hitschfeld, J F Munoz, S Vicuna, Alfonso Mejia and S Jankowfsky, 2017, "A GIS-based urban and peri-urban landscape representation toolbox for hydrological distributed modeling", Environmental Modeling and Software, 91, pp. 168–185
  • X. Yang, S. Sharma, R. Siddique, S. Greybush and A Mejia, 2017, "Postprocessing of GEFS reforecasts over the U.S. middle Atlantic region", Monthly Weather Review, 145, (5), pp. 1641–1658
  • S Pavlovic, S Perica, M. St Laurent and A Mejia, 2016, "Intercomparison of selected fixed area areal reduction factor methods", Journal of Hydrology, 537, pp. 419-430
  • T. Jovanovic, A. Mejia, H. Gall and J. Gironas, 2016, "Effect of urbanization on the long-term persistence of streamflow records", Physica A: Statistical Mechanics and its Applications, 447, pp. 208–221
  • H McMillan, A Montanari, C Cudennec, H Savenije, H Kreibich, T Krueger, J Liu, A Mejia, Anne Van Loon, H Aksoy, G Di Baldassarre, Y Huang, D Mazvimavi, M Rogger, B Sivakumar, T Bibikova, A Castellarin, Y Chen, D Finger, A Gelfan, D M Hannah, A Y Hoekstra, H Li, S Maskey, T Mathevet, A Mijic, A Pedrozo-Acuna, M J Polo, V Rosales, P Smith, A Viglione, V Srinivasan, E Toth, R van Nooyen and J Xia, 2016, "Panta Rhei 2013-2015: Global perspectives on hydrology, society and change", Hydrological Sciences Journal, 61, (7), pp. 1174-1191
  • R. Siddique, A. Mejia, J. Brown, S. Reed and P. Ahnert, 2015, "Verification of precipitation forecasts from two numerical weather prediction models in the middle Atlantic region of the USA: A precursory analysis to hydrologic forecasting", Journal of Hydrology, 529, (3), pp. 1390–1406
  • W. Paterson, R. Rushforth, B. L Ruddell, M. Konar, I C Ahams, J. Gironas, A. Mijic and A. Mejia, 2015, "Water footprint of cities: A review and suggestions for future research", Sustainability, 7, (7), pp. 8461-8490
  • A Mejia, F Rossel, J Gironas and T Jovanovic, 2015, "Anthropogenic controls from urban growth on flow regimes", Advances in Water Resources, 84, pp. 125-135
  • A Mejia, E Daly, F Rossel, T Jovanovic and J Gironas, 2014, "A stochastic model of streamflow for urbanized basins", Water Resources Research, 50, (3), pp. 1984–2001
  • F J Rossel, J Gironas, F Mejia, F Rodriguez and A Rinaldo, 2014, "Spatial characterization of catchment dispersion mechanisms in an urban context", Advances in Water Resources, 74, pp. 290-301
  • A I Mejia, 2013, "Assessment of hydrologic controls on the applicability of routing methods", Journal of Hydrologic Engineering, 18, (8), pp. 948-957
  • A I Mejia, 2013, "Scaling of the network instantaneous response function from basin geomorphology and hydraulic geometry", Journal of Hydrologic Engineering, 18, (12), pp. 1786-1789
  • A I Mejia and S M Reed, 2011, "Evaluating the effects of simplified routing and parameterized cross section shapes with a coupled distributed hydrologic and hydraulic model", Journal of Hydrology, 409, (1-2), pp. 512-524
  • A I Mejia and S M Reed, 2011, "Role of channel and floodplain cross-section geometry in the basin response", Water Resources Research, 47, (9), pp. 1-15
  • A I Mejia and G E Moglen, 2010, "Impact of the spatial distribution of imperviousness on the hydrologic response of an urbanizing basin", Hydrological Processes, 24, (23), pp. 3359–3373
  • A I Mejia and G E Moglen, 2010, "Spatial distribution of imperviousness and the space-time variability of rainfall, runoff generation, and routing", Water Resources Research, 46, (7), pp. 1-14
  • A I Mejia and G E Moglen, 2009, "Spatial patterns of urban development from optimization of flood peaks and imperviousness-based measures", Journal of Hydrologic Engineering, 14, (4), pp. 416-424
  • A I Mejia and J D Niemann, 2008, "Identification and characterization of dendritic, parallel, pinnate, trellis, and rectangular drainage networks based on deviations from planform self-similarity", Journal of Geophysical Research, 113, (F2), pp. 1-21

Conference Proceedings

Research Projects

Honors and Awards


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