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

The IDS Group is a research group with Chemical and Bioresource Engineering at CSU. IDS develops
software engineering applications with advanced modeling techniques for natural resource
management and civil engineering.
I/O
Abbreviation for input/output.
Infiltration
Water moving into the ground from a surface supply such as precipitation or irrigation. Infiltration rates
are reckoned on the basis that the water is entire water. (Rice (1991))
Initial Conditions
The conditions that prevail at the time of initiation of a transient. (Rice (1991))
Insolation
(Contracted from incoming solar radiation.) Solar radiation received at the earth's surface. (Rice
(1991))
Instream Flow Needs
Those habitat requirements within the running water ecosystem related to current velocity and depth
which present the optimum conditions of density (or diversity) or physiological stability to the aquatic
organism being examined. (Rice (1991))
Instream Use
Any use of water which does not require diversion from a water course or impoundment. (Rice (1991))
Intent to Appropriate
That condition in which the mind has formed a definite plan to divert or store water, create the means
to do so, and apply such water to a beneficial use. (Rice (1991))
Internet
A widely-available computer network that uses the TCP/IP communication protocol. High-speed
backbone links are available throughout the country. Slower speed links allow paying network
subscribers to access the Internet. The network allows file transfer and logins to computers at remote
sites.
Interstate
Having to do with two or more states. (Rice (1991))
In The Gage
Term used when dealing with natural flows and base flows, and referring to human influences on
natural river flows. "In the gage" means that diversions are not subtracted from a recorded streamflow
(which is subject to diversions) when calculating a "natural" flow. Instead, the diversions are treated in
computations as if they are part of the natural system.
Intrastate
Having to do with matters confined to one state. (Rice (1991))
IRIX
SGI's version of UNIX.
Irrigated Area
The area upon which water is artificially applied for the production of crops. (Rice (1991))
Irrigation
The application of water to crops, lawns, and gardens by artificial means to supplement natural
precipitation. Water can be applied by spreading, sprinkling, or dripping. (Rice (1991))
Irrigation Efficiency
The ratio of the volume of water consumed by a specific beneficial use as compared to the volume of
water delivered. Efficiency may be computed in terms of the water diverted at the ditch headgate or the
water delivered to the farm headgate. (Rice (1991))
Irrigation Return Flow
Applied water which is not consumptively used and returns to a surface water or groundwater supply.
In water right litigation the definition may be restricted to measurable water returning to the stream
from which it was derived. (Rice (1991))
Irrigation, Supplemental
An additional irrigation water supply which supplements the initial or primary supply. (Rice (1991))