WSPC12493 ‎(2)‎

• File Number: 8220.101.10
• Description: Colorado River Water Projects - Glen Canyon Dam-Lake Powell - Adaptive Management
• State: CO
• Basin: Colorado Mainstem
• Date: 4/1/1996
• Author: DOI-BOR
• Title: CRSSez - Annual Colorado River System Simulation Model - Overview-Users Manual - Update of 04-01-96 - With Revisions of 09-01-96 - 04-01-96
• Water Supply Pro - Doc Type: Report/Study

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SOFTWARE WARRANTY

If this software does not work as described, tough. If its use
costs you millions of dollars, tough. The united States
government and its agents retain the right to do the minimum
required under the law which is probably nothing. This is about
the same worthless warranty that comes with most software.

OVERVIEW

CRSSez simulates annual operations of Lake Powell and Lake Mead
on a PC computer with MS-DOS. Methods are adapted from
Reclamation's official monthly model Colorado River Simulation
System (CRSS) for use on an annual basis. The gains and
depletions in CRSSez have been lumped above and below Mead, and
above Powell. Reservoirs above Powell are operated as one
reservoir. Reservoirs below Mead are scheduled to be at the same
storage level at the end of every year and can be ignored except
for evaporation. The current version has been updated to provide
Quarterly values at the 3 reservoirs plus Parker Dam. Monthly
release values for Hoover, Davis, and Parker are also computed.
Comparison of 85 traces for 56 years between EZ and CRSS show
annual average differences for Powell and Mead contents to be
less than 2% and releases to be less than 1%.

CRSSez is intended for use in planning studies for comparing
differences in operations. It was developed by the USBR River
Operations Branch in Boulder City in 1991 to evaluate water
banking options directed by the Lower Basin states for inclusion
in proposed "Regulations for Administering Entitlement to
Colorado River Water in the Lower Colorado Basin". It was also
adopted for use in studies performed under the Colorado River
Management and Planning Studies program. Banking and various
other operations could not readily be incorporated into the
complex CRSS model. An EZ simulation run of 85 traces for 56
years will take about 1 minute on a 486-66Mhz PC. Use of EZ as a
planning tool offers several practical advantages as multiple
alternatives can be considered, displayed, and studied in a
limited time.

DESCRIPTION OF CRSSez BASIN AND DATA

Why not use CRSS?:

USBR's full CRSS mainframe model is made up of 25 reaches with up
to 10 diversion points and 10 inflow points per reach. Each
diversion point can be made up of 10 separate users. There are
12 reservoirs that are individually operated to meet downstream

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