Water-Resources Investigations Report 93-4076, Hydro-Climatic Data Network (HCDN):  Streamflow Data Set, 1874-1988

In Reply Refer To:                                   July 20, 1993
Mail Stop 415


Subject:  Water-Resources Investigations Report 93-4076, 
          Hydro-Climatic Data Network (HCDN):  Streamflow Data 
          Set, 1874-1988, by J.R. Slack, Alan M. Lumb, and 
          Jurate Maciunas Landwehr

This memorandum is to announce the availablity of the subject 
report and to make a distribution to Districts and other selected 
offices.  This Water-Resources Investigations Report is unique in 
that it is a CD-ROM.  The only printed text is that on the front 
and back cover sheets of the protection case.

The data set on the CD-ROM consists of a cumulative 73,231 water 
years of daily, monthly, and annual streamflow data collected 
during 1874-1988 at 1,659 stations.  These stations, called the 
"Hydro-Climatic Data Network (HCDN),"  were selected from the 
total network operated over the years by the U.S. Geological 
Survey (USGS).  Criteria for selection were established for 
climatic analysis and were intended to minimize effects due to 
human activities, provide long and accurate records, and give 
reasonably complete geographical coverage of the United States.

Researchers and other investigators are expected to use this data 
set where high-quality, long-term streamflow records with a 
minimum of anthropogenic effects are needed for regional or 
national analyses.  The HCDN is the first national network of 
stations the USGS has selected that has data suitable for climatic 
and other similar analyses.

The CD-ROM presents data as three formats: a text file, a 
straight-forward binary, and a database for use with the USGS 
Watershed Data Management System.  The data in text-file format 
are readable on IBM-compatible personal computers, Data General 
work stations, and Macintosh computers.  However, the other two 
formats and accompanying software are made available only for 
IBM-compatible computers.

Copies of the CD-ROM may be obtained from the authors or from the 
Office of Surface Water (OSW).  The contents of the CD-ROM can be 
accessed over Internet via anonymous ftp (file transfer protocol) 
to directory hcdn92 at


A companion document to the CD-ROM, in which the contents of the 
HCDN are defined, was announced in OSW Technical Memorandum     
No. 93.02.  It is Open-File Report 92-129, Hydro-Climatic Data 
Network:  A USGS streamflow data set for the United States for the 
study of climatic variations, 1874-1988, by J.R. Slack and Jurate 
Maciunas Landwehr.  An electronic copy of the Open-File Report is 
contained on the CD-ROM.  Paper copies are available from the 
authors or from the OSW.

                                 Charles W. Boning, Chief
                                 Office of Surface Water

                   Chief, Branch of Regional Research, 
                     NR, CR, WR (2 copies each)
                   Regional Surface Water Specialists, 
                     NR, CR, SR, WR