S10_11-15-04

• Basin: Statewide
• Title: SWSI Phase 1 Report - Section 10 Basin-Specific Options
• Date: 11/15/2004
• Author: CWCB
• SWSI - Doc Type: Final Report

Section 10
Basin-Specific Options
10.1.8 Rio Grande Basin
10.1.8.1 Rio Grande Basin Gap Analysis Issues
As presented in Section 6, the gap analysis process
presented at the Basin Roundtable Technical Meetings
provided information on the Identified Projects and
Processes that M&I water providers are reasonably
confident of implementing to meet 2030 water demands.
Key activities related to water supply planning and basin
specific issues raised throughout the meetings and SWSI
process with respect to M&I and SSI demands in the Rio
Grande Basin include the following:
10.1.8.3 Rio Grande Basin Summary of
Conditional Storage Rights
To portray the conditional storage rights present in the
Rio Grande Basin, the area was described using water
districts as shown in Figure 10-20.
The eight water districts in the Rio Grande Basin can
also be described using the main stream systems, which
are shown in Table 10-16.
Table 10-16 Rio Grande Basin Water Districts and
Associated Stream Names
^ There are not any existing or projected SSI uses.
^ There is potential for additional M&I conservation and
some providers are starting to install water meters.
^ Groundwater is physically available for most
anticipated M&I growth.
^ Augmentation of all new wells is required.
Agricultural issues noted throughout SWSI in the Rio
Grande Basin include:
^ Agricultural use is at unsustainable levels of pumping
in the closed basin and water levels have dropped in
the unconfined aquifer and in parts of the confined
aquifer.
^ Up to 100,000 acres of agricultural land may need to
no longer be irrigated in order to return and maintain
groundwater at historical levels.
^ It will be a challenge to achieve voluntary reduction of
irrigated acres and offset the economic impacts of
reducing irrigated acreage.
^ There will be some minor potential loss of irrigated
acres as a result of dry-up and transfer of the
consumptive use for M&I augmentation.
10.1.8.2 Rio Grande Basin Supply Availability
Issues
In the Rio Grande Basin, the following issues were
identified regarding supply availability:
^ There is very limited availability of water for
development under the Rio Grande Compact.
Sections 4 and 7 describe the compact and supply
availability.
^ RICDs and CWCB instream flow water rights may
impact the ability to manage water supplies upstream
of these water rights.
~
$~ole'ri~ice Wo~e' $upplY Initia~ive
20 Rio Grande River
21 Alamosa River
22 Conejos River
24 Culebra Creek
25 San Luis Creek
26 Saguache Creek
27 Camero/ La Grita Creek
35 Trinchera Creek
As shown in Table 10-17, four water districts in the Rio
Grande Basin contain a total of 134,105 AF of conditional
storage rights, which exceeds the amount that can be
developed given compact limitations. Approximately
8,600 AF of these rights have priority dates of 1900 to
1920. The remaining have priority dates that begin in
1960 and that extend to present day. The numbers
presented in this table describe the total volume of
conditional rights by priority time period and not the
number of individually decreed conditional rights. These
priority time periods are based on adjudication dates and
used solely for the purpose of aggregating the numerous
conditional rights into a table for presentation. The
number, rather than volume, of conditional rights is
presented in Appendix H.
Water District 20 in the Rio Grande Basin has the largest
volume of conditional storage rights. This is depicted in
Table 10-17 and also presented graphically in
Appendix H. There is approximately 120,000 AF of
conditional storage rights in this water district with priority
dates beginning in 1900. Figure 10-21 focuses on the
priority date of the conditional storage rights. The largest
portion of storage rights have priority dates of between
1960 and 1980, followed by the 1980 to 2002 time
period.
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