CRDSS_Task1_14-5_CUModelsInShortList

• Title: CRDSS Task 1.14-5 Consumptive Use Models - Consumptive Use Models Included in the Short List
• Description: The purpose of this task memorandum is to describe the reasons for including consumptive use models in the “short list.” The short list was composed of five models that went through a more rigorous evaluation phase.
• Decision Support - Doc Type: Task Memorandum
• Date: 1/9/1995
• DSS Category: Consumptive Use
• DSS: Colorado River
• Basin: Colorado Mainstem
• Contract/PO #: C153658, C153727, C153752
• Grant Type: Non-Reimbursable
• Bill Number: SB92-87, HB93-1273, SB94-029, HB95-1155, SB96-153, HB97-008
• Prepared By: Riverside Technology inc.

SMB
SMB is a privately owned computer model developed by W.W. Wheeler and Associates; the technical
contact is Ivan Walter. This model was written in FORTRAN and will run on an IBM-compatible PC
and on UNIX workstations. This model uses four different methods for estimating daily and monthly ET
for grass and alfalfa as a reference crop. These methods are Penman-Monteith, 1982 Kimberly-Penman,
1972 Kimberly-Penman, and Hargraves method.
The model can estimate the daily and monthly CIR by considering percolation and run off. The effective
rainfall is estimated as total minus the amount lost to deep percolation and runoff. The general function
of the model is to estimate a daily soil moisture budget that is used in calculating monthly values for
water depletion.
This model was incorporated in the short list because of the accuracy of the method, it is written in
FORTRAN, and it uses several combination methods. The code is not in the public domain, but W.W.
Wheeler and Associates has provided a preliminary license agreement that would provide access to the
source code to the State for use in the CRDSS. Some restrictions on the distribution of the source code
are present in the license agreement, and the State and W.W. Wheeler and Associates would need to
coordinate the distribution of any source code to consultants. The model has been well tested and is
written in a modular form. This model meets the criteria for technical capabilities of calculating a
reference crop ET for use in the CRDSS. However, based on the amount of available resources for the
completion of Phase IIa of the CRDSS, it was recommended that the incorporation of a reference crop
method not be included in Phase IIa of the CRDSS.
TABLE 1
EVALUATION OF MODELS INCLUDED IN THE SHORT LIST
CROPWAT and
CriteriaXCONS2 BASIN CRPSMSMB
1. Agency and USBR, Denver, Mike USBR, Nebraska, L. Utah State W.W. Wheeler and
Contact Madigan (702) 293- Myler (307) 261- University, Bob Hill Associates, Ivan
8120 5621 [phone] Walter (303) 761-
4130
2. What is the FORTRAN FORTRAN FORTRAN FORTRAN
programming
language?
3. What is the IBM-PC/UNIX UNIX Workstation IBM-PC IBM-PC/UNIX
original development Workstation Workstation
platform?
4. Methods used to SCS-BC Jensen-Haise and 2, 6, 8, 9, and 10 1, 2, 5, and 9 from
calculate ET. TR-21 SCS - BC from the overview the overview task
TR-21 task memorandum memorandum
5. Type of method CIR = ET - Eff. Rain CIR = Etp - Seasonal CIR = ET - CIR = beginning soil
used to determine Infiltration + change total precipitation - moisture - end soil
CIR. in soil moisture change in soil moisture + ET + deep
budget + deep moisture. percolation -
percolation precipitation + runoff
6. Model-specific precipitation, percent soil type, irrigation soil properties, soil characteristics,
data required in daylight, crop name, efficiency, rainfall, rainfall, crop spring or fall tillage,
addition to data listed season length, start- infiltration soil phenological data, irrigation frequency
for methods in table end growth dates curves, crop acreage, growing season data, or MAD dates,
1. and growing season and crop acreage, growing season data,
irrigation schedule precipitation
3
A275 01.09.95 1.14-5 CSU IDS