Glossary

• Title: Glossary of CDSS Terms
• Description: Glossary of terms used throughout the CDSS documentation.
• Decision Support - Doc Type: Report
• Date: 7/5/2005
• DSS: All
• Basin: Statewide
• Prepared By: CWCB

Creek
A natural stream of water, normally smaller than, and often tributary to, a river. (Rice (1991))
CriticalYear
Usually considered a year in which the annual precipitation was considerably less than average and
runoff in most of the streams was low. The critical year is used to test the dependibility of water rights
under worst-case conditions. (Rice (1991))
Crop Coefficients
Crop coefficient is the ratio of evapotranspiration occurring with a specific crop at a specific stage of
growth to reference crop evapotranspiration at that time. This definition is not for the coefficient K used
in the Blaney-Griddle evapotranspiration method.
CRSM -Colorado River Simulation Model
The Colorado River simulation model used by the USBR and being used as a the big river model for
the CRDSS. CRSM is being replaced at the USBR by Prism (CRSS).
CRSS -Colorado River Simulation System
Several software components that are used to model the Colorado River system. CRSM is one of the
components of CRSS, as are TAPEDIT, MHYDRO, and SMDID (CRSS).
CSU
Colorado State University
CU
Consumptive Use (model)
University of Colorado
DB -Database
A collection of data, typically organized on a computer using a commercial software package.
Decree
An official document issued by the court defining the priority, amount, use, and location of a water right
or plan of augmentation. When issued, the decree serves as a mandate to the state engineer to
administer the water rights involved in accordance with the decree. (Rice (1991))
Deep Percolation
The drainage of soil water by gravity below the maximum effective depth of the root zone. (Rice
(1991))
Dependable Yield
See firm yield.
Dew Point Temperature
The temperature at which air becomes saturated and produces dew.
Direct Flow Right
A right defined in terms of discharge and which must be put to use more or less promptly following
diversion from the source. (Rice (1991))
Discharge
The volume of water passing a particular point in a unit of time. Units of discharge commonly used
include cubic feet per second (cfs) or gallons per minute (gpm). (Rice (1991))
Ditch
A narrow trench cut into the surface of the ground to transport water from a stream to a point of use
away from a stream. (Rice (1991))
Diversion
Removing water from its natural course or location, or controlling water in its natural course or location,
by means of a ditch, canal, flume, reservoir, bypass, pipeline, conduit, well, pump, or other structure or
device. (Rice (1991))
Diversion Records
Record of the daily flow in cubic feet per second for a ditch or other diversion structure. Compiled by
the district water commissioner, ditch rider, or other water official, diversion records are generally on
file and available for review at the state engineer's office. (Rice (1991))
Division Engineer