Water Resources Applications Software

Geochemical || Ground Water || Surface Water || Water Quality || General

Summary of WDM

       wdm - Watershed Data Management file system

       The Watershed Data Management (WDM) system provides a systematic
       approach to the storage and retrieval of data required to operate
       hydrologic, hydraulic, and water-quality models.  The WDM system
       uses a well-defined binary, direct-access file structure accessed
       through a library of routines to create a file, add data to the
       file, replace data in the file, get data from the file and delete
       data from the file.  Five categories of data may be stored in WDM
       file data sets:  time series, tables, text, vectors, and space-time.
       A comprehensive set of attributes is available for documenting and
       describing individual data sets.

       The WDM library of routines enables expedient input, update, and
       output of data.  WDM files allow comprehensive specification of data
       attributes, multiple time steps in single time-series data sets,
       user-defined formats for data stored as tables, compression of data,
       improved speed and flexibility of interaction between a model and
       its data base, and automatic file maintenance as the user adds,
       modifies, or deletes data sets.  The WDM system allows multiple
       models, requiring different data types and data with different time
       steps, to use a common data base.

       The WDM library is included in the LIB distribution.  It requires
       the UTIL and ADWDM libraries from the LIB distribution.

       A WDM file is a binary, direct-access file used to store hydrologic,
       hydraulic, meteorologic, water-quality, and physiographic data.  The
       WDM file is organized into data sets.  Each data set contains a
       specific type of data, such as streamflow at a specific site or air
       temperature at a weather station.  Each data set contains attributes
       that describe the data, such as station identification number, time
       step of data, latitude, and longitude.  A WDM file may contain a
       single data set or as many as 200,000 data sets.  A data set may be
       described by a few attributes or by hundreds of attributes.  Data
       can be added, deleted, and modified without restructuring the data
       in the file.  Space from deleted data sets is reused.

       The original design and implementation of time-series data sets in
       the WDM file was a cooperative effort between the USGS and the Soil
       Conservation Service in 1983.  The USGS and EPA have implemented the
       tables, text, vectors, and space-time data sets since then.
       Originally implemented on Prime and Vax minicomputers and MS-DOS
       compatible personal computers (1983-1991).

       Version 3.1 1996/12/11 - Added new subroutine WDBSGL to retrieve
          latitude and longitude from a data set.

       Version 3.0 1996/03/01 - Include file names changed to lower case.
          Corrected the valid minimum for attribute JANMIN (changed from
          0.0 to no lower limit).

       Version 2.1 1994/08/11 - Updates

       Version 2.0 1994/05/27 - General release

       Version 1.0 1992 - General release, ported to UNIX platform.

       NOTE:  Version numbers and dates are for the entire lib set of
             libraries.  A new version does not necessarily indicate that
             the WDM library has been changed.

       WDM is written in Fortran 77 with the following extension: use of
       include files. The WDM library requires the ADWDM and UTIL

       The WDM file was initially created for use by the program ANNIE for
       storage, manipulation, graphical display, and statistical analysis
       of watershed data.  With the implementation of other programs
       capable of accessing data stored in WDM files, each WDM file serves
       as a common data base from which data are shared among multiple
       applications and across different computer platforms.  Examples of
       programs using WDM files include DR3M, HSPF, PRMS, and SWSTAT, which
       performs the statistical analyses previously found in ANNIE.

       A subroutine reference guide is provided with the distribution.

       Lumb, A.M., Carsel, R.F., and Kittle, J.L., Jr., 1988, Data
          management for water-quality modeling development and use:
          Proceedings of the International Conference on Interactive
          Information and Processing Systems for Meteorology, Oceanography,
          and Hydrology.

       Flynn, K.M., Hummel, P.R., Lumb, A.M., and 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 Report 95-4085, 211 p.

       Landers, M.N., Mueller, D.S., and Martin, G.R., 1996, Bridge scour
          data management system user's manual: U.S. Geological Survey
          Open-File Report 95-754, 72 p.

       Lumb, A.M., McCammon, R.B., and Kittle, J.L., Jr., 1994, Users
          manual for an expert system (HSPEXP) for calibration of the
          Hydrologic Simulation Program--Fortran:  U.S. Geological Survey
          Water-Resources Investigations Report 94-4168, 102 p.

       Operation and Distribution:
          U.S. Geological Survey
          Hydrologic Analysis Software Support Program
          437 National Center
          Reston, VA 20192

       Official versions of U.S. Geological Survey water-resources analysis
       software are available for electronic retrieval via the World Wide
       Web (WWW) at:


       and via anonymous File Transfer Protocol (FTP) from:

         (path: /pub/software).

       The WWW page and anonymous FTP directory from which the LIB software
       can be retrieved are, respectively:


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