WSP12125

• File Number: 8102
• Description: Arkansas River Hydrology
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 1/1/1997
• Author: USGS
• Title: Description of the Program Changes - 1989-97- and a User Manual for a Transit-Loss Accounting Program Applied to Fountain Creek Between Colorado Springs and the Arkansas River-Colorado
• Water Supply Pro - Doc Type: Report/Study

0,1J423

the ditch-accounts data. The program display also
queries the user for the required inputs of the
return-flow, gaging-station, and diversion
discharge data; the input data are redisplayed to
allow for error checking and to reinput the data if
nece55ary. Maintenance of the accounting
program primarily requires the annual archiving
of the output files generated by the program; the
archiving procedure is partly automated through
the use of a computer scri pt code.

INTRODUCTION

Since 1989, the Fountain Creek transit-loss
accounting program (hereinafter, usually referred to as
the accounting program or the program) has been used
to account for return flows of transmountain waler
(water imponed from the western slope of the Conti-
nental Divide) in Fountain Creek between the City of
Colorado Springs (CCS) and the Arkansas River
(fig. I). The program incorporates the results of a
study completed in ] 987 (Kuhn, 1988) that developed
methods to (I) determine transit losses for the trans-
mountain return flows (TRF's) in Fountain Creek and
(2) quantify the TRF's and the associated transit losses
on a daily basis. The results of the 1987 study would
enable the CCS to totally reuse its trans mountain
water supplies because, under Colorado water law,
transmountain water can be used and reused until
totally consumed. provided that such water can be
identified and quantified (Radosevich and others.
] 976, p. 88-89. 93-95), The water exchanges and
other arrangements that would be used by the CCS to
use and reuse the TRF's are described in a repon by
the Gronning Engineering Company (1986).
The accounting program is a FORTRAN
computer program that enables daily accounting of
(I) the TRF's, (2) transit losses for the TRF's, and (3)
the native streamflows (NSP's) (nontransmountain
water) in Fountain Creek. Following a period of
testing to ensure the accuracy of the program and to
familiarize users with the operating procedures, the
accounting program was put in operation in April
1989,
After 1989, the procedures that the CCS used in
the use and reuse of the TRF's were changed. Also,
during that time, the Fountain Valley Conduit, a
component of the transmountain Pryingpan-Arkansas

Project (PAP) (Bureau of Reclamation, 1972), became
fully operational, ,The conduit provides supplementary
municipal water to the CCS and other nearby commu-
nities, The Southeastern Colorado Water Conservancy
District (SECWCD) manages the transmountain water
imponed by the PAP and needed to be able to account
for the additional TRF's in Fountain Creek. The modi-
fications in the CCS TRF use and reuse program, the
introduction of FAP TRF's into Fountain Creek, and
the associated changes in the accounting procedures
for these TRF's required that changes be made to the
accounting program,
The accounting program has been in operation
for about 8 years and has been changed considerably
during that time; however. the program and the
changes never have been documented completely. To
ensure that the accounting program can continue to be
used as long as needed, the use of the program and the
changes made to it need to be documented. Docu-
menting the accounting program not only benefits
future applications or changes of the accounting
program, but it also improves the underwUlding of the
program by those currently ( 1997) using it. Therefore,
in 1997. the V,S, Geological Survey (USGS), in coop-
eration with the City of Colorado Springs, Department
of Public Utilities, and the SECWCD, completed a
study to document the program changes and the use of
the Fountain Creek transit-loss accounting program.

Purpose and Scope

: I

This repon (l) describes the computational
steps and procedures of the original transit-loss
accounting program; (2) describes the changes that
were made to the program in 1991-92 and in 1994--95;
(3) provides a user manual for the current (1997)
version of the program; and (4) documents the proce-
dures for maintaining the current version of the
accounting program, the auxiliary programs, and the
numerous output data files generated during each year
of operating the accounting program. This repon
describes the assumptions and methods used in the
accounting program. the required inputs, and the
resulting outputs, Tbe descriptions of the program are
not a line-by-line description of the computer code,
but rather a general explanation of the computational
steps. Presentation of the computer codes is beyond
the scope of this repan,

2 ' Descriptions of the Program Change8 (1989--97) and 8 User Manual for a Transit-Lou Accounting Program
Applied to Fountain Creek. Between Colorado Springs and the Arkansaa River, Colorado.