PUBLICATIONS--Release of two new reports documenting computer programs




WGS-Mail Stop 411                               December 5, 1989


OFFICE OF GROUND WATER TECHNICAL MEMORANDUM NO. 90.02

Subject:  PUBLICATIONS--Release of two new reports documenting
                        computer programs

The two subject reports are:

Leake, S.A., and Prudic, D.E., 1988, Documentation of a computer
program to simulate aquifer-system compaction using the
modular finite-difference ground-water flow model:  U.S.
Geological Survey Open-File Report 88-482, 80 p.

Prudic, David E., 1989, Documentation of a computer program to
simulate stream-aquifer relations using a modular, finite-
difference, ground-water flow model: U.S. Geological Survey
Open-File Report 88-729, 113 p.

The report by Leake and Prudic (1988) documents a new program, the
Interbed-Storage Package, that simulates changes in ground-water
storage caused by compressible interbeds in an aquifer system.
This package has been incorporated into the modular computer
program of McDonald and Harbaugh (1988, TWRI, Book 6, Chapter A1).
In addition to accounting for changes in storage, the package also
calculates permanent (inelastic) compaction as well as recoverable
(elastic) compaction of sediments.  The report also describes the
Time-Variant Specified Head Package which was developed to allow
constant head nodes to take on different values for each time
step.  The authors have sent copies of the report to each District
Office, Regional Ground-Water Specialist, and RASA project chief.
Additional copies of the report are available from Stan Leake
(WRD, Tucson, Arizona).

The report by Prudic (1989) documents a new program, the
Streamflow-Routing Package, that can be used to simulate
interaction between surface streams and ground water.  This
package is not a true surface-water flow model but rather is an
accounting program that tracks the flow in one or more streams in
addition to computing leakage between the streams and the aquifer
system.  The stage in each reach can be computed using the Manning
formula.  This package has been incorporated into the modular
computer program of McDonald and Harbaugh (1988, TWRI, Book 6,
Chapter A1).  A copy of this report is attached and is being
distributed to District, State, Regional, and some subdistrict
offices of the Division.

Water Resources Division employees may obtain the computer
programs described in these reports from the Software Exchange
System (SOFTEX) on the QVARSA Prime computer.  The SOFTEX entry
for the Interbed-Storage Package is AZSAL 00003. The SOFTEX entry
for the Streamflow-Routing Package is NVSAW00001.

We recommend that this information be brought to the attention of
technical and management personnel concerned with ground-water
studies.



                               Eugene P. Patten
                               Chief, Office of
                               Ground Water

Attachment

WRD Distribution:  A & B (memo only),
                   S, FO, & PO (memo w/attachment).