


     dr3m(1)          U.S. Geological Survey (wrdapp)          dr3m(1)


     NAME
            dr3m - Distributed Routing Rainfall-Runoff Model--version II

     ABSTRACT
            DR3M is a watershed model for routing storm runoff through a
            Branched system of pipes and (or) natural channels using rainfall as
            input.  DR3M provides detailed simulation of storm-runoff periods
            selected by the user.  There is daily soil-moisture accounting
            between storms.  A drainage basin is represented as a set of
            overland-flow, channel, and reservoir segments, which jointly
            describe the drainage features of the basin.  This model is usually
            used to simulate small urban basins.  Interflow and base flow are
            not simulated.  Snow accumulation and snowmelt are not simulated.

     METHOD
            The rainfall-excess components include soil-moisture accounting,
            pervious-area rainfall excess, impervious-area rainfall excess, and
            parameter optimization.  The Green-Ampt equation is used in the
            calculations of infiltration and pervious area rainfall excess.  A
            Rosenbrock optimization procedure may be used to aid in calibrating
            several of the infiltration and soil-moisture accounting parameters.
            Kinematic wave theory is used for both overland-flow and channel
            routing.  There are three solution techniques available:  method of
            characteristics, implicit finite difference method, and explicit
            finite difference method.  Two soil types may be defined.  Overland
            flow may be defined as turbulent or laminar.  Detention reservoirs
            may be simulated as linear storage or using a modified-Puls method.
            Channel segments may be defined as gutter, pipe, triangular cross
            section, or by explicitly specifying the kinematic channel
            parameters alpha and m.

     HISTORY
            1991 - DR3M-version II, added option to output simulated time-series
               data to Watershed Data Management (WDM) file.  Output file
               modified to reduce width from 132 characters to 80 characters or
               less.

            1984 - DR3M-version II, WDM file replaces "card" input of time-
               series data.

            1982 - DR3M-version II, added two solution techniques for kinematic
               wave routing.  Added a file link to DR3M-QUAL.  Improved general
               output.

            1978 - Original DR3M version, incorporated the routing component
               from a version of the Massachusetts Institute of Technology
               catchment model into the lumped parameter rainfall-runoff model.

            1972 - A lumped parameter rainfall-runoff model for small rural
               watersheds

     DATA REQUIREMENTS
            Daily precipitation, daily evapotranspiration, and short-interval
            precipitation are required.  Short-interval discharge is required



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     dr3m(1)          U.S. Geological Survey (wrdapp)          dr3m(1)


            for the optimization option and to calibrate the model.  These time
            series are read from a WDM file.  Roughness and hydraulics
            parameters and sub-catchment areas are required to define the basin.
            Six parameters are required to calculate infiltration and soil-
            moisture accounting.  Up to three rainfall stations may be used.
            Two soil types may be defined.  A total of 99 flow planes, channels,
            pipes, reservoirs, and junctions may be used to define the basin.

     OUTPUT OPTIONS
            The computed outflow from any flow plane, pipe, or channel segment
            for each storm period may be written to the output file or to the
            WDM file.  A summary of the measured and simulated rainfall, runoff,
            and peak flows is written to the output file.  A flat file
            containing the storm rainfall, measured flow (if available), and
            simulated flow at user selected sites can be generated.  A flat file
            for each storm containing the total rainfall, the measured peak flow
            (if available), and the simulated peak flow for user-selected sites
            can be generated.

     SYSTEM REQUIREMENTS
            UNIX-based computers (supported:  Data General AViiON and Sun
            SPARCstation).

            DOS-based computers having a math coprocessor and 2 mb of memory
            (supported: IBM-compatible computers with a 386 or greater
            processor).

            DR3M is written in Fortran.  Generally, it is easily installed on
            other platforms.

     DOCUMENTATION
            Alley, W.M., and Smith, P.E., 1982, Distributed routing rainfall-
               runoff model--version II:  U.S. Geological Survey Open-File
               Report 82-344, 201 p.

     RELATED DOCUMENTATION
            Flynn, K.M., Hummel, P.R., Lumb, A.M., Kittle, J.L., Jr., 1995,
               User's manual for ANNIE, version 2, a computer program for
               interactive hydrologic data management:  U.S. Geological Survey
               Water-Resources Investigations 95-4085, 211 p.

     REFERENCES
            Dawdy, D.R., Lichty, R.W., and Bergmann, J.M., 1972, A rainfall-
               runoff simulation model for estimation of flood peaks for small
               drainage basins: U.S. Geological Survey Professional Paper 506-B,
               28 p.

            Dawdy, D.R., Schaake, J.C., Jr., and Alley, W.M., 1978, User's guide
               for distributed routing rainfall-runoff model:  U.S. Geological
               Survey Water-Resources Investigations Report 78-90, 146 p.

            Doyle, H.W., Jr., and Miller, J.E., 1980, Calibration of a
               distributed routing rainfall-runoff model at four urban sites
               near Miami, Florida: U.S. Geological Survey Water-Resources



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     dr3m(1)          U.S. Geological Survey (wrdapp)          dr3m(1)


               Investigations Report 80-1, 87 p.

            Guay, J.R., and Smith, P.E., 1988, Simulation of quantity and
               quality of storm runoff for urban catchments in Fresno,
               California:  U.S. Geological Survey Water-Resources
               Investigations Report 88-4125, 76 p.

            Leclerc, Guy, and Schaake, J.C., Jr., 1973, Methodology for
               assessing the potential impact of urban development on urban
               runoff and the relative efficiency of runoff control
               alternatives:  Ralph M. Parsons Laboratory Report no. 167,
               Massachusetts Institute of Technology, 257 p.

     TRAINING
            Watershed Systems Modeling I (G0083), offered annually at the USGS
            National Training Center.

            Watershed Systems Modeling II (G0183), offered upon request at the
            USGS National Training Center.

     CONTACTS
            Operation and Distribution:
               U.S. Geological Survey
               Hydrologic Analysis Software Support Team
               Kate Flynn
               437 National Center
               Reston, VA 22092

               h2osoft@usgs.gov

            Latest version by anonymous ftp from:
                  h2o.usgs.gov
                  /pub/software/surface_water/dr3m

     SEE ALSO
            annie - Program to list, table, plot data in a WDM file
            dr3m-qual - Multi-event urban runoff quality model
            iowdm - Program to store time-series data in a WDM file
            wdm - Watershed Data Management system


















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