S5_11-15-04

• Basin: Statewide
• Title: SWSI Phase 1 Report - Section 5 Projected Water Use
• Date: 11/15/2004
• Author: CWCB
• SWSI - Doc Type: Final Report

Section 5
Projected Water Use
~
5.3 Projected 2030 Agricultural
Demand
Projections of 2030 agricultural demands and supporting
data are presented in Table 5-8. As a result of the
estimated potential changes in irrigated acres,
agricultural demands and their associated gross
diversions are shown as decreasing in the Arkansas,
Colorado, Gunnison Rio Grande, and South Platte
Basins. Demands in the Dolores/San Juan/San Miguel
and Yampa/ White Green
Basins may have a net
increase if additional
agricultural supplies are
developed to provide for the
increase in irrigated acres.
Gunnison Basin agricultural
demands could increase if
additional supplies are
developed to reduce shortages
on existing irrigated lands. The
North Platte Basin is not
expected to have a significant
To better anticipate future conditions, it is helpful to
examine existing supply and demand. Current
agricultural water shortages (crop requirement - supply
greater than zero) for the basins with DSS tools have
been evaluated. There are a number of factors that
impact the calculation of water shortages such as the
relative priority of water rights, the physical supply of
water available for diversion at any given point, and
irrigation practices. These factors are discussed in
greater detail below. First, under the Colorado prior
2%
12% '
^ ,~qricultural
^ M&I
^ ssi
appropriation system, water is
allocated based on the priority of the
water right, so that during times of
average to less than average
streamflows, some water rights will
not be in priority, resulting in a
shortage of water to meet irrigation
water requirements. The South
Platte and Arkansas Basins have
many irrigation ditches that are
water-short as a result of the
extensive appropriation and
Figure 5-9 competition for water in these
change in demands. Relative Pr~~or~ions ofAgricultural, M~l, basins. The development of the
and ssl water use in 203o Colorado-Big Thompson (CBT)
A summary of total projected Project in the South Platte and the
Colorado agricultural use relative to M&I and SSI Frying Pan-Arkansas (Fry-Ark) Project in the Arkansas
demands is shown in Figure 5-9. As can be seen, Basin were developed to address a portion of the water
agricultural use is expected to still comprise the majority shortages in these basins.
of these uses in 2030.
Current:
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Statew~itle Water Supply Inii'iative
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