Physical Characteristics that Determine Flow in the Unsaturated Zone

Flow in the unsaturated zone profoundly influences the degradation as well as the loss and replenishment of available water resources. Unsaturated-zone physical characteristics, such as hydraulic conductivity and water retention, are essential to the determination of water and solute fluxes into groundwater and to the understanding of surface-subsurface interactions. The theory describing these unsaturated-zone influences has not been adequately tested and may in fact be invalid for certain important cases. Limitations of present laboratory and field techniques are a major hindrance to large-scale hydrological application of unsaturated flow theory because critical physical characteristics cannot be measured with the required speed and accuracy. The objectives are to test the validity of existing theories related to unsaturated-zone fluxes and correct or extend them where necessary; to develop fast, accurate, practical methods for measuring unsaturated-zone fluxes and the physical characteristics that determine them; to apply and promote routine use of these experimental and theoretical methods in hydrological studies where the unsaturated zone plays an important role; and to assess the importance of complicating influences (termperature gradients, dispersion, hysteresis, etc.) on water and solute fluxes. For additional information about work being done by this project, see project's home page.

REPORTS PUBLISHED 1999-2008

Delin, G.N., Healy, R.W., Lorenz, D.L., and Nimmo, J.R., 2007, Comparison of local- to regional-scale estimates of ground-water recharge in Minnesota, USA: Journal of Hydrology, v. 334, p. 231-249. (on-line abstract of journal article)

Heppner, C.S., Nimmo, J.R., Folmar, G.J., Gburek, W.J., and Risser, D.W., 2007, Multiple-methods investigation of recharge at a humid-region fractured rock site, Pennsylvania, USA: Hydrogeology Journal, v. 15, p. 915-927. (on-line abstract of journal article)

Nimmo, J.R., 2007, Simple predictions of maximum transport rate in unsaturated soil and rock : Water Resources Research, v. 43, W05426, doi:10.1029/2006WR005372. (on-line journal article)

Nimmo, J.R., Herkelrath, W.N., and Laguna Luna, A.M., 2007, Physically based estimation of soil water retention from textural data: General framework, new models, and streamlined existing models: Vadose Zone Journal, v. 6, no. 4, p. 766-773. (on-line abstract of journal article)

Nolan, B.T., Healy, R.W., Taber, P.E., Perkins, K.S., Hitt, K.J., and Wolock, D.M., 2007, Factors influencing ground-water recharge in the eastern United States: Journal of Hydrology, v. 332, p. 187-205. (on-line abstract of journal article)

Perkins, K.S., and Winfield, K.A., 2007, Property transfer modeling to estimate unsaturated hydraulic conductivity of deep sediments at the Idaho National Laboratory, Idaho: U.S. Geological Survey Scientific Investigations Report 2007-5093, 22 p. (on-line abstract or on-line publication in pdf format, 1.07 MB

Nimmo, J.R., and Perkins, K.S., 2006, Effect of soil disturbance on aquifer recharge - case study on the Snake River Plain, Idaho National Laboratory, USA: 34th Congress, Bejing, October 9-13, 2006, International Association of Hydrogeologists [Proceedings] - CD only.

Winfield, K.A., Nimmo, J.R., Izbicki, J.A., and Martin, P.M., 2006, Resolving structural influences on water-retention properties of alluvial deposits: Vadose Zone Journal, v. 5, p. 706-719, doi:10.2136/vzj2005.0088 (on-line abstract of journal article)

Caputo, M.C., and Nimmo, J.R., 2005, Quasi-steady centrifuge method for unsaturated hydraulic properties: Water Resources Research, v. 41, doi:10.1029/2005WR003957 (on-line abstract of journal article)

Heppner, C.S., and John R. Nimmo, J.R., 2005, A computer program for predicting recharge with a master recession: U.S. Geological Survey Scientific Investigations Report 2005-5172, 8 p. (on-line abstract or on-line report in pdf format, 226 KB)

Nimmo, J.R., 2005, Unsaturated-zone flow processes, in Anderson, M.G., and Bear, J., eds., Encyclopedia of Hydrological Sciences: Part 13--Groundwater: Chichester, UK, Wiley, v. 4, p. 2,299-2,322, doi:10.1002/0470848944.hsa161 (on-line abstract) .

Nimmo, J.R., Healy, R.W., and Stonestrom, D.A., 2005, Aquifer recharge, in Anderson, M.G., and Bear, J., eds., Encyclopedia of Hydrological Science: Part 13--Groundwater: Chichester, UK, Wiley, v. 4, p. 2,229-2,246, doi:10.1002/0470848944.hsa161a (on-line abstract)

Nimmo, J.R., and Landa, E.R., 2005, The soil-physics contributions of Edgar Buckingham: Soil Science Society of America Journal, v. 69, p. 328-342. (on-line abstract of journal article)

Perkins, K.S., 2005, Aquifer recharge estimates based on unsaturated zone measurements, southern New Jersey: San Jose State University, M.S. thesis, 87 p.

Rousseau, J.P., Landa, E.R., Nimmo, J.R., Cecil, L.D., Knobel, L.L., Glynn, P.D., Kwicklis, E.M., Curtis, G.P., Stollenwerk, K.G., Anderson, S.R., Bartholomay, R.C., Bossong, C.R., and Orr, B.R., 2005, Review of the transport of selected radionuclides in the interim risk assessment for the Radioactive Waste Management Complex, Waste Area Group 7 Operable Unit 7-13/14, Idaho National Engineering and Environmental Laboratory, Idaho: U.S. Geological Survey Scientific Investigations Report 2005-5026, 283 p. in 2 volumes. (on-line volume 1 (text) in pdf format, 2.4 MB or on-line volume 2 (figures) in pdf format, 3.3 MB)

Šimunek, J., and Nimmo, J.R., 2005, Estimating soil hydraulic parameters from transient flow experiments in a centrifuge using parameter optimization technique: Water Resources Research, v. 41, no. 4, doi:10.1029/2004WR003379. (on-line abstract of journal article)

Winfield, K.A., 2005, Development of property-transfer models for estimating the hydraulic properties of deep sediments at the Idaho National Engineering and Environmental Laboratory, Idaho: U.S. Geological Survey Scientific Investigations Report 2005-5114, 59 p. (on-line abstract or on-line report in pdf format, 1.56MB)

Heilweil, V.M., Solomon, D.K., Perkins, K.S., and Ellett, K.M., 2004, Gas-partitioning tracer test to quantify trapped gas during recharge: Ground Water, v. 42, p. 589-600. (on-line abstract)

Nimmo, J.R., 2004, Aggregation - Physical aspects in Hillel, D., ed., Encyclopedia of Soils in the Environment: London, Elsevier, p. 28-35.

Nimmo, J.R., 2004, Porosity and Pore Size Distribution, in Hillel, D., ed. Encyclopedia of Soils in the Environment: London, Elsevier, p. 295-303.

Nimmo, J.R., Rousseau, J.P., Perkins, K.S., Stollenwerk, K.G., Glynn, P.G., Bartholomay, R.C., and Knobel, L.L., 2004, Hydraulic and geochemical framework of the Idaho National Engineering and Environmental Laboratory vadose zone: Vadose Zone Journal, v. 3, p. 6-34. (on-line abstract)

Baehr, A.L., Kaufman, L.J., Perkins, K.S., and Nolan, B.T., 2003, Estimating spatial variability of recharge in southern New Jersey from unsaturated-zone measurements: U.S. Geological Survey Water-Resources Investigations Report 02-4288, 31 p. (on-line abstract or on-line report in pdf format - 3.6MB)

Landa, E.R., and Nimmo, J.R., 2003, The life and scientific contributions of Lyman J. Briggs: Soil Science Society of America Journal, v. 67, p. 681-693. (on-line abstract)

Nimmo, J.R., 2003, How fast does water flow in an unsaturated macropore?: Evidence from field and lab experiments, in Alvarez-Benedi, J., and Marinero, P., eds., Estudios de la Zona No Saturada del Suelo, v. VI: Valladolid, Spain, Instituto Tecnologico de Castilla y Leon, p. 1-8.

Nimmo, J.R., Stonestrom, D.A., and Healy, R.W., 2003, Aquifer recharge in Stewart, B.A., and Howell, T.A., eds., Encyclopedia of Water Science: New York, Marcel Dekker, p. 22-25.

Perkins, K.S., 2003, Measurement of sedimentary interbed hydraulic properties and their hydrologic influence near the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory: U.S. Geological Survey Water-Resources Investigations Report 03-4048, 19 p. (on-line report in pdf format)

Su, G.W., Nimmo, J.R., and Dragila, M.I., 2003, Effect of isolated fractures on accelerated flow in unsaturated porous rock: Water Resources Research, v. 39, no. 12, p. 1-1 - 1-5. (on-line abstract)

Winfield, K.A., 2003, Spatial variability of sedimentary interbed properties near the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory: U.S. Geological Survey Water-Resources Investigations Report 03-4142, 36 p. (on-line abstract or on-line report, pdf format 1.1MB)

Constantz, J., Jasperse, J., Seymour, D., and Su, G., 2002, Use of temperature to estimate streambed conductance, Russian River, California in Kenny, J.F., ed., Ground Water/Surface Water Interactions, AWRA 2002 Summer Specialty Conference Proceedings: American Water Resources Association, Middleburg, Virginia, p. 595-600.

Cox, M., Rosenberry, D., Su, G., Conlon, T., Lee, K., and Constantz, J., 2002, Comparison of methods to estimate streambed seepage rates in Kenny, J.F., ed., Ground Water/Surface Water Interactions, AWRA 2002 Summer Specialty Conference Proceedings: American Water Resources Association, Middleburg, Virginia, p. 519-523.

Haverkamp, R., Reggiani, P., and Nimmo, J.R., 2002, Property-transfer models in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 759-761, 781-782.

Nimmo, J.R., 2002, Meter-to-kilometer scaling of preferential flow in the unsaturated zone, in Findikakis, A.N., ed., Bridging the Gap between Measurements and Modeling in Heterogeneous Media--Proceedings of the International Groundwater Symposium, Berkeley, California, March 25-28, 2002: IAHR, Madrid, Spain, CD-ROM.

Nimmo, J.R., 2002, What measurable properties can predict preferential flow?, in Kheornenromne, I., ed., Transactions of the 17th World Congress of Soil Science, Bangkok, Thailand, August 14-21, 2002: International Union of Soil Science, Vienna, p. 324:1-11.

Nimmo, J.R., 2002, Water retention and storage -- Guidelines for method selection, in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 716-720.

Nimmo, J.R., 2002, Guidelines for method selection [water retention and storage], in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 716-720.

Nimmo, J.R., 2002, Property transfer from particle and aggregate size to water retention, in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 777-780.

Nimmo, J.R., Deason, J.A., Izbicki, J.A., and Martin, P., 2002, Evaluation of unsaturated zone water fluxes in heterogeneous alluvium at a Mojave Basin site: Water Resources Research, v. 38, no. 10, p. 33-1 - 33-13. (on-line abstract)

Nimmo, J.R., and Perkins, K.S., 2002, Aggregate stability and size distribution, in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 317-328.

Nimmo, J.R., Perkins, K.S., and Lewis, A.M., 2002, Steady-state centrifuge, in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 903-916, 933-993.

Nimmo, J.R., Perkins, K.S., Rose, P.A., Rousseau, J.P., Orr, B.R., Twining, B.V., and Anderson, S.R., 2002, Kilometer-Scale Rapid Transport of Naphthalene Sulfonate Tracer in the Unsaturated Zone at the Idaho National Engineering and Environmental Laboratory: Vadose Zone Journal, v. 1, p. 89-101. (on-line abstract)

Nimmo, J.R., and Winfield, K.A., 2002, Water retention and storage -- Miscellaneous methods in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 710-714, 717-720.

Perkins, K.S., Nimmo, J.R., Rose, P.A., Rousseau, J.P., Orr, B.R., Twining, B.V., and Anderson, S.R., 2002, Flow system analysis using a surface-applied tracer at the Idaho National Engineering and Environmental Laboratory, Idaho, in Aiken, G.R., and Kuniansky, E.L., eds., U.S. Geological Survey Artificial Recharge Workshop Proceedings, Sacramento, California: U.S. Geological Survey Open-File Report 02-89, p. 82-83. (on-line report)

Winfield, K.A., and Nimmo, J.R., 2002, Water retention and storage -- Controlled liquid volume in Dane, J.H., and Topp, G.C., eds., Methods of Soil Analysis -- Part 4, Physical Methods: Madison, Soil Science Society of America, p. 698-703, 717-720.

Nimmo, J.R., Perkins, K.S., Rose, P.A., Rousseau, J.P., Orr, B.R., Twining, B.V., and Anderson, S.R., 2001, Kilometer-scale rapid flow in a fractured-basalt unsaturated zone at the Idaho National Engineering and Environmental Laboratory in Kueper, B.H., Novakowski, K.S., and Reynolds, D.A., eds., Fractured Rock 2001 Conference Proceedings, March 26-28, 2001, Toronto, Canada, CD-ROM.

Su, G.W., Geller, J.T., Pruess, K., and Hunt, J.R., 2001, Solute transport along preferential flow paths in unsaturated fractures: Water Resources Research, v. 37, p. 2481-2491.

Su. G.W., Nimmo, J.R., and Dragila, M.I., 2001, Fluid flow mechanisms in an unsaturated porous rock containing a single fracture, in Kueper, B.H., Novakowski, K.S., and Reynolds, D.A., eds., Fractured Rock 2001 Conference Proceedings, March 26-28, 2001, Toronto, Canada, CD-ROM.

Lewis, 2000, Recharge estimates obtained from centrifuge measurements, Abo Arroyo, New Mexico: San Jose State University, M.A. thesis, 71 p.

Nimmo, J.R. Lewis, A.M., and Winfield, K.A., 2000, Discernable large and small-scale features affecting recharge in Abo Arroyo and similar basins, in Cole, J.C., ed., U.S. Geological Survey Middle Rio Grande Basin Study - Proceedings of the Fourth Annual Workshop, Albuquerque, New Mexico, February 15-16, 2000: U.S. Geological Survey Open-File Report 00-488, p. 41-43.

Perkins, K.S., 2000, Hydrologic and meteorological data for an unsaturated-zone study area near the Radioactive Waste Management Complex, Idaho National Engineering and Environmental Laboratory, Idaho, 1997 to 1999: U.S. Geological Survey Open-File Report 00-248, CD-ROM and 18 p.

Perkins, K.S. and Nimmo, J.R., 2000, Measurement of hydraulic properties of the B-C interbed and their influence on contaminant transport in the unsaturated zone at the National Engineering and Environmental Laboratory, Idaho: U.S. Geological Survey Water-Resources Investigations Report 00-4073, 30 p. (on-line abstract)

Winfield, K.A., 2000, Factors controlling water retention of alluvial deposits, western Mojave Desert: San Jose State University, M.S. thesis, 88 p.

Lewis, A.M., Nimmo, J.R., and Stonestrom, D.A., 1999, Recharge estimates interpreted from centrifuge hydraulic property measurements of core samples from Abo Arroyo, Middle Rio Grande Basin, New Mexico, in Bartolino, J.R., ed., U.S. Geological Survey Middle Rio Grande Basin Study--Proceedings of the Third Annual Workshop, Albuquerque, New Mexico, February 24-25, 1999: U.S. Geological Survey Open-File Report 99-203, p. 69-70.

Morel-Seytoux, H.J., and Nimmo, J.R., 1999, Soil water retention and maximum capillary drive from saturation to oven dryness: Water Resources Research, v. 35, p. 2031-2041. (on-line abstract)

Nimmo, J.R., 1999, Accounting for fractures and other macropores in predictions of unsaturated hydraulic conductivity, in Faybishenko, B., ed., Dynamids of Fluids in Fractured Rocks: Concepts and Recent Advances--Proceedings of International Symposium in Honor of Paul Witherspoon, Berkeley, CA, February 10-12, 1999, LBNL-42718, p. 110-113.

Nimmo, J.R., 1999, Predicting soil-water retention and hydraulic conductivity from textural and structural information in van Genuchten, M.T., Leij, F., and Wu, L., eds, Characterization and measurement of the hydraulic properties of unsaturated porous media, Part 2, Proceedings of the International Workshop on Characterization and Measurement of the Hydraulic Properties of Unsaturated Porous Media, Riverside , California, October 22-24, 1997: University of California Press, p. 923-930.

Nimmo, J.R., Shakofsky, S.M., Kaminsky, J.F., and Lords, G.S., 1999, Laboratory and field hydrologic characterization of the shallow subsurface at an Idaho National Engineering and Environmental Laboratory waste-disposal site: U.S. Geological Survey Water-Resources Investigations Report 99-4263, 31 p. (on-line abstract)

Su, G.W., Geller, J.T., Pruess, K., and Wen, 1999, Experimental studies of water seepage and intermittent flow in unsaturated, rough-walled fractures: Water Resources Research, v. 35, no. 4, p. 1019-1037.

FOR ADDITIONAL INFORMATION ON THIS PROJECT, CONTACT:
John R. Nimmo
U.S. Geological Survey, 345 Middlefield Rd, MS421, Menlo Park, CA 94025
Email: jrnimmo@usgs.gov
Telephone: 650-329-4537

For information on additional projects in the National Research Program, see Indexes to NRP projects and bibliographies