Water Resources Applications Software

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

Summary of IOWDM

     iowdm - Input and Output for a Watershed Data Management
     (WDM) file

     IOWDM is designed to reformat data to and from a WDM file.
     Data in selected WATSTORE card-image formats and flat file
     formats can be added to a WDM file.

     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.

     Version 4.1 2002/02/25 - Updated to use latest libanne
        libraries, version 4.0 dated September 27, 2001.
        Calculation for last available group for attribute data
        and time series data have been corrected.

     Version 4.0 2001/02/08 - In the Input/Timeseries option,
        increased the maximum allowed value for TSBYR from 2000
        to 1000000.

     Version 4.0 2000/11/01 - The Input menu now includes an
        option to save summary information to a file.  All WDM
        data sets now contain the date the data set was created
        and the date the data set was last modified.

     Version 3.0 - There was no 3.0 distribution.

     Version 2.4 1998/06/18 - Change in Input/Peak option.
        Partial duration peaks, (peaks above a base and less than
        an annual maximum, record type "4") are not longer stored
        in the WDM file.  These peaks were causing incorrect
        results in the peakfq program.  peakfq analysis should be
        checked to verify that partial duration peaks were not

     Version 2.3 1998/01/13 - Correction in flat time-series
        option.  In some cases of long records with time step
        shorter than a day, a part of the record was shifted in
        time.  Also, in some instances where the user specified
        the begin and end date for the data, the last time step
        was not written to the WDM file.  Data sets can be
        checked for this problem by examining data values at the
        end of the record.

     Version 2.2 1996/03/01 - Added flat file options.

     Version 2.1 1994 - Updates.

     1994 - Distributed as iowdm2.0.  Option to read WATSTORE n-
        day high/low flows added to the iowdm.1.0 version.

     1992 - Distributed as iowdm.1.0.  IOWDM was revised to use
        the AIDE user interface.  This version read WATSTORE
        basin characteristics, annual peak flows, daily values,
        and unit values.  There was no output option.

     1989 - Distributed with ANNIE0189.  Used an interactive,
        question-answer, scrolling user interface.  Read WATSTORE
        basin characteristics, annual peak flows, daily values,
        unit values, and n-day high/low flows, HSPF sequential
        files and PLTGEN files, a user-defined flat file, and
        Carter daily and unit values files.  Wrote WATSTORE daily
        and unit values.

     Data in the following WATSTORE card-image formats may be
     written to a WDM file:

        o daily values (3 cards with optional Z, H, N, and 2
        o unit values (B-cards with optional Z, H, N, and 2
        o basin and streamflow characteristics (1 and 2 cards)
        o n-day high and/or low flow (2 and 3 cards)
        o annual peak flows (3 and 4 cards with optional Z, H, N,
          and 2 cards)

     Flat file formats:
        o time series, RDB
        o time series, tabular
        o attributes, tabular
        o attributes, list

     The IOWDM file writes data from formatted input files to the
     WDM file.  No other output options are currently supported.

     IOWDM is written in Fortran 77 with the following extension:
     use of include files.  The WAIDE, AIDE, WDM, ADWDM, and UTIL
     libraries from LIBANNE are required to recompile.  For more
     information, see System Requirements in LIBANNE.

     IOWDM is used in support of projects that use a WDM file for
     data management.

     Text files are included with the distribution.

     Lumb, A.M., Kittle, J.L., Jr., and Flynn, K.M., 1990, Users
        manual for ANNIE, a computer program for interactive
        hydrologic analyses and data management: U.S. Geological
        Survey Water-Resources Investigations Report 89-4080, 236
        p.  (Documents the 1990 version included in the ANNIE

     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 Report
        95-4085, 211 p.

     There are no regularly scheduled classes for IOWDM.  The use
     of the program is included as part of the introductory
     exercises in other classes.

     Watershed Systems Modeling I (SW2008TC), offered annually at
     the USGS National Training Center.

     Statistical Approach to Surface-Water Hydrologic Analysis
     (SW2011TC), offered annually at the USGS National Training

     River Basin Water-Quality Modeling (ID2146TC), offered
     annually at the USGS National Training Center.

     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
     IOWDM software can be retrieved are, respectively:


     for information on ordering printed copies of USGS

     annie(1) - Program to list, table, plot data in a WDM file

     hass-cui(1) - Character-based user interface

     wdm(1) - Watershed Data Management system

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