WSPC01394

• File Number: 8460.500
• Description: Platte River Basin - Endangered Species Issues - South Platte Recovery Program
• State: CO
• Basin: South Platte
• Water Division: 1
• Date: 10/1/1996
• Title: South Platte Agreement - Irrigation Water Conservation - Opportunities and Limitations in Colorado - Report of the Agricultural Water Conservation Task Force
• Water Supply Pro - Doc Type: Report/Study

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reducing nonbeneficial consumptive use, the amount of water involved is likely to be so small that the
economic incentive for any single operator is minimal, Of the management practices mentioned previously,
only those involving changes in cropping patterns could result in salvaging significant quantities of water by
decreasing beneficial consumptive use, The changes in cropping practices involved, however, are substantial,
and economic barriers to this transition in cropping can be significant. For example, shifts from feed crops
(com or alfalfa) to melons in the Arkansas River basin can result in significant water salvage because of the
seasonal consumptive use of melons is much lower than that of either com or alfalfa, However, this type of
cropping change involves making wholesale modifications in fann operations and entering a more dynamic
marketing environment. Thus, this change in cropping practices is not likely to occur on a widespread basis,
Economic barriers to salvaging water through changing cropping practices can be overcome with transition
from irrigated to dryland farming upon the sale and transfer of agricultura1 water to urban use, This type of
transition has occurred on relatively large acreages of fOImerly irrigated land in the South Platte and Arkansas
River basins,
The existence of economic incentives for swface water users to implement practices that result in more
efficient diversion depends on the disposition of the resulting saved water, Growers are free to retain control
of this water if the accrued savings can be used to extend supplies under the terms of the existing decree, In
many cases, irrigators are shan of water for a portion of the growing season, so there is an economic
incentive to use the saved water to fill shortages, If, however, the grower is \DIable to use the saved water in
this manner, the saved water automatically becomes part of the stream system and available to other users,
The incentives for adopting deficit irrigation practices are lacking, partly because of institutional barriers
to transfer of a portion of the historic consumptive use within any given decree, These barriers include
problems with quantifying the portion of the historic consumptive use to be transferred and administering the
resulting change, One alternative to pennanent transfers of a portion of consumptive use is dry-year option
contracts between agricultural and municipal users, Under these arrangements, agricultura1 users would be
paid to fallow land during short-term periods when supplies fall far short of total demands within the basin,

Issues Associated with Irrigation Water Conservation

General imolications of water conservation oractices, In watershed basins where water is derived from
swface diversions or shallow alluvial aquifers, the adoption of conservation practices that decrease either
nonbeneficial or beneficial consumptive use will have min;m.l effect on hydrology at the basin level, because
return flows are not affected. There is concern that decreases in nonbeneficial consumptive use could threaten

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