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
10.1.5 Dolores/San Juan/
San Miguel Basin
10.1.5.1 Dolores/San Juan/San Miguel 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 include
the following:
^ This multi-basin area of the state is extremely diverse
with changing demographics in the Pagosa Springs-
Bayfield-Durango corridor. This rapidly growing area
has areas of localized water shortage and is
transitioning from mining/agricultural to tourism,
recreation, and a retirement/second home area. It will
likely not be financially feasible to serve some
unincorporated areas not served by water districts
due to the high costs of transmission and delivery
infrastructure.
^ The Cortez area remains strongly agricultural but is
also seeing rapid growth with retirees moving to the
area. The San Miguel area is a mix of recreation and
tourism along with a strong desire to maintain
agriculture.
^ The San Miguel subbasin will need the development
of additional supplies to meet projected M&I demand
^ The Dolores subbasin has a gap in providing for
augmentation of well pumping and surface water
diversions upstream of CWCB instream flow rights. A
finding of de minimus impacts on CWCB instream
flow rights can also address these gaps where
depletions are minor.
Agricultural issues noted throughout SWSI in the
Dolores/San Juan/San Miguel Basin include:
^ Agricultural shortages greater than 10 percent were
identified in many water districts as shown in
Section 5.
^ A potential project was identified for supplemental
irrigation water supply in San Miguel Basin.
~~
^ Long Hollow Reservoir can regulate La Plata River
flows required under the La Plata Compact and
maximize supplies for use in Colorado.
^ Supplies have been identified to irrigate an additional
4,000 acres in the Dolores Water Conservancy
District.
10.1.5.2 Dolores/San Juan/San Miguel Supply
Availability Issues
In the Dolores/San Juan/San Miguel Basin, the following
issues were identified regarding supply availability:
^ Overall water supply availability in the San Juan
subbasin is good. The M&I allocations in the Dolores
and Animas-La Plata Projects can provide the
supplies to meet these future M&I needs. The
challenge will be to develop the infrastructure to
deliver project water to the areas of need. In addition,
Colorado River Compact allocations to New Mexico
have not been an issue to date, but may affect supply
availability in the future.
^ State Engineer probable maximum precipitation and
spillway sizing requirements render some new
reservoir projects financially infeasible due to high
spillway construction costs.
- Additional storage could be realized in existing
reservoirs if spillway requirements were less
stringent.
^ Colorado River Compact
- The Colorado River Compact places pressure on
uses of the San Juan River because New Mexico's
primary source of the upper basin supplies is the
San Juan River.
- Concern over a potential compact call during
severe and sustained drought.
- Allocation of water within the State of Colorado if
there is a compact call due to severe and
sustained drought.
^ Endangered Species
- The success of the Endangered Species program
is critical to help protect current and future water
uses.
^ The potential Durango RICD may reduce free river
conditions and require that new upstream diversions
develop supplies to augment depletions.
~~
Sfvtewide Woter Supoly Initiofive
10-16 S:\REPORT\WORD PROCESSING\REPORT\S10 11-11-04.DOC