New & Noteworthy
Press Release: Study Explores Groundwater and Geothermal Energy in DroughtStricken Eastern Oregon and Neighboring States
Technical Announcement: USGS Issues Revised Framework for Hydrogeology of Floridan Aquifer
Press Release: High Plains Aquifer Groundwater Levels Continue to Decline
Regional Groundwater Availability Study Geospatial Data
Press Release: USGS Assesses Current GroundwaterQuality Conditions in the Williston Basin Oil Production Area
Past listings...
USGS Groundwater Watch
USGS maintains a network of active wells to provide basic statistics about groundwater levels.
Other Water Topics
Water Resources
Groundwater
Surface Water
Water Quality
Water Use
USGS in Your State
USGS Water Science Centers are located in each state.

Software and Models, Methods for Estimating Groundwater
Recharge In Humid Regions
Sorted by Date
Method 
Category 
Program 
Author 
Date 
Title 
Base Flow 
Streamflow 
BFI 
Wahl, K.L. and Wahl, T.L. 
1988 
A computer program for determining an index to base flow 
Regression 
Regionalization 
GLSNet 
Tasker, G.D., and Stedinger, J.R., 1989, An operational GLS model for hydrologic regression: Journal of Hydrology, v. 111, p. 361375. 
1989 
Tasker, G.D., and Stedinger, J.R., 1989, An operational GLS model for hydrologic regression: Journal of Hydrology, v. 111, p. 361375. 
GW Models 
Groundwater

MODFE 
Torak, L.J. 
1993 
A MODular FiniteElement model (MODFE) for areal and axisymmetric groundwaterflow problems 
New Jersey 
Water Budget 
DGS992 
Charles, E.G. 
1993 
A method for evaluating groundwater recharge areas in New Jersey 
Base Flow 
Streamflow 
PART 
Rutledge, A.T. 
1993 
Computer programs for describing the recession of groundwater discharge and for estimating mean groundwater recharge and discharge from streamflow records 
HELP3 
Water Budget 
HELP 
Schroeder, P.R., Aziz, N.M., Lloyd, C.M., and Zappi, P.A. 
1994 
The hydrologic evaluation of landfill performance (HELP) model, user’s guide for version 3 
Base Flow 
Streamflow 
HYSEP 
Sloto, R.A., and Crouse, M.Y. 
1996 
HYSEP: a computer program for streamflow hydrograph separation and analysis 
Watershed Models 
Streamflow 
HSPF 
Bicknell, B.R., Imhoff, J.C., Kittle, J.L., Jr., Donigian, A.S., Jr., and Johanson, R.C. 
1997 
Hydrological Simulation ProgramFortran, User's manual for version 11 
RecessionCurve Displacement 
Streamflow 
RORA 
Rutledge, A.T. 
1998 
Computer programs for describing the recession of groundwater discharge and for estimating mean groundwater recharge and discharge from streamflow data – update 
UZ Models 
Unsaturated Zone 
VS2D 
Hsieh, P.A., Wingle, William, and Healy, R.W. 
2000 
VS2DIA graphical software package for simulating fluid flow and solute or energy transport in variably saturated porous media 
Watershed Models 
Streamflow 
PRMS 
Leavesley, G.H., Lichty, R.W., Troutman, B.M., and Saindon, L.G., 1983, PrecipitationRunoff Modeling System: User's Manual: U.S. Geological Survey WaterResources Investigations 834238, 207 p. 
2000 
Leavesley, G.H., Lichty, R.W., Troutman, B.M., and Saindon, L.G., 1983, PrecipitationRunoff Modeling System: User's Manual: U.S. Geological Survey WaterResources Investigations 834238, 207 p. 
RecessionCurve Displacement 
Streamflow 
PULSE 
Rutledge, A.T. 
2002 
User guide for the PULSE program: 
GW Models 
Groundwater

SUTRA 
Voss, C. I., and Provost, A.M., 
2002 
SUTRA, A model for saturatedunsaturated variabledensity groundwater flow with solute or energy transport 
Watershed Models 
Streamflow 
SWAT 
Neitsch, S.L., Arnold, J.G., Kiniry, J.R., Williams, J.R. 
2005 
Soil and water assessment tool  theoretical development 
Base Flow 
Streamflow 
WHAT 
K.J. Lim, B.A. Engel, Z. Tang, J. Choi, K. Kim, S. Muthukrishnan, and D. Tripathy 
2005 
Web GISbased Hydrograph Analysis Tool, WHAT 
GW Models 
Groundwater

MODFLOW 
Harbaugh, A.W. 
2005 
A modular threedimensional finitedifference groundwater flow model 
