Transcript Slide 1

Overview of the Colorado River Basin
Water Supply and Demand Study
Water Center at Colorado Mesa University
Upper Colorado River Basin Water Forum
October 31, 2011
Ted Kowalski,
Chief of the Interstate and Federal Section,
Colorado Water Conservation Board
Colorado River Basin Water
Supply and Demand Study
 Overview and Status of
the Study
 Historical and Future
Water Supply and
Demand
 Next Steps
Colorado River Basin Water
Supply and Demand Study
 Study Objective
 Assess future water supply and demand
imbalances and develop/evaluate
opportunities for resolving imbalances
 Studied being conducted by Reclamation
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


and the Basin States, in collaboration with
stakeholders throughout the Basin
Study began in January 2010 and will be
completed by July 2012
Email:
[email protected]
Website:
http://www.usbr.gov/lc/region/programs/
crbstudy.html
A planning study – will not result in any
decisions
Historic Colorado River Water Supply & Use (Annual)
6
Study Outreach
Hydropower
Recreation
Western, CREDA.
others
Ecosystem
NGO collaborative.
others
NPS,
Concessionaires,
others
Native American
Tribes and
Communities
Lower Basin,
Upper Basin
Colorado River
Basin Water
Supply &
Demand Study
Endangered
Species
FWS, others
Other
Water Deliveries
Water Districts
(agriculture, M&I use)
General public, other
interested
stakeholder groups
Options for Participation in the Study
(not mutually exclusive)
 Monitor project website, webinars, emails
 Review and comment on products
 Receive periodic updates (formal and/or informal)
 Establish points-of-contact with the “Study Team”
(Reclamation and the Basin States representatives)
 Participate in Study working groups (“Sub-Teams”)
 Other
Study Phases and Tasks
Phase 1:
Water Supply
Assessment
Phase 2:
Water Demand
Assessment
Phase 3:
System Reliability
Analysis
Phase 4:
Development &
Evaluation of
Opportunities
1.1 – Select
Methods to
Estimate Current
Supply
2.1 – Select Methods
to Estimate Current
Demand
3.1 – Identify
Reliability Metrics
4.1 – Develop
Opportunities
1.2 – Select
Methods to Project
Future Supply
Formulate
Approach
to Include
Uncertainty
2.2 – Select Methods
to Project Future
Demand
1.3 – Conduct
Assessment of
Current Supply
1.4 – Conduct
Assessment of
Future Supply
Develop
Future
Supply and
Demand
Scenarios
Green denotes essentially complete
3.2 – Estimate
Baseline System
Reliability
2.3 – Conduct
Assessment of
Current Demand
3.3 – Project Future
System Reliability
2.4 – Conduct
Assessment of
Future Demand
3.3.5-3.3.8 – Project
Future Reliability with
Opportunities
4.2 –
Evaluate and Refine
Opportunities
4.3 –
Finalize Opportunities
Interim Report No. 1
Interim reports provide a
comprehensive “snapshot” of the
Study’s progress to date
• Approach facilitates the
integration of continuous
technical developments and the
ongoing input of stakeholders
 Interim Report No. 1 is a “snapshot”
as of January 31, 2011 and is
available at:
http://www.usbr.gov/lc/region/pro
grams/crbstudy.html
•
Historic Colorado River Water Supply & Use
(10-year Running Average)
7
Natural Flow Colorado River at Lees Ferry Gaging Station, Arizonao
2011
Colorado River at Lees Ferry, AZ - Natural Flow
30
30
Annual Flow (MAF)
Average
10-yr Average
25
25
20
20
15
15
10
10
5
5
0
0
1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010
Provisional data, subject to change
Water Year
Estimated values for 2009-2011
Water Year Snowpack and Precipitation
as of September 12, 2011
Colorado River Basin
above Lake Powell
Water Year
Precipitation
(year-to-date)
123%
Source: CBRFC
Colorado River Basin Storage
(as of September 11, 2011)
Current Storage
Percent
Full
MAF
Elevation
(Feet)
Lake Powell
73%
17.75
3,654
Lake Mead
49%
12.80
1,114
Total System
Storage*
65%
38.85
NA
*Total system storage was 33.50 maf or 56% this time last year
Addressing an Uncertain Future
 The path of major influences on the Colorado River
system is uncertain and can not be represented by a single
view
• An infinite number of
plausible futures exist
• A manageable and
informative number of
scenarios are being
developed to explore the
broad range of futures
(adapted from Timpe and Scheepers, 2003)
Water Supply Scenarios *
 Observed Resampled: hydroclimatic trends and variability are similar
to the past 100 years
 Paleo Resampled: future hydroclimatic trends and variability are
represented by reconstructions of streamflow for a much longer period
in the past (nearly 1250 years) that show expanded variability
 Paleo-Conditioned: future hydrologic trends and variability are
represented by a blend of the wet-dry states of the longer paleoreconstructed period (nearly 1250 years), but magnitudes are more
similar to the observed period (about 100 years)
 Downscaled GCM Projected: future climate will continue to warm with
regional precipitation and temperature trends represented through an
ensemble of future downscaled GCM projections
* Preliminary – Subject to change
Projections of Natural Flow at Lees Ferry
2011 – 2060 Period Mean Annual Flows
Observed
102 Traces
Mean = 15002
Direct Paleo
1244 Traces
Mean = 14675
Paleo Conditioned
1000 Traces
Mean=
14937
112 Traces
Climate Projections Mean = 13588
20,000
20,000
20,000
20,000
18,000
18,000
18,000
18,000
16,000
16,000
16,000
16,000
14,000
14,000
14,000
14,000
12,000
12,000
12,000
12,000
10,000
10,000
10,000
10,000
8,000
8,000
8,000
8,000
1988 – 2007 period mean
Preliminary
Box represents 25th – 75th percentile,
whiskers represent min and max, and
triangle represents mean of all traces
Water Demand Scenarios *
 Current Trends: growth, development patterns, and institutions
continue along recent trends
 Economic Slowdown: low growth with emphasis on economic efficiency
 Expansive Growth: economic resurgence (population and energy) and
current preferences toward human and environmental values **
 Enhanced Environment and Healthy Economy: expanded environmental
awareness and stewardship with growing economy **
* Preliminary – Subject to change
** Additional “branches” possible depending upon assumed trajectory of specific socio-economic factors
System Reliability Metrics (Metrics)

Metrics are measures that indicate
the ability of the system to meet the
needs of Basin resources
 Metrics will be used to quantify the
impacts to Basin resources from
future supply and demand
imbalances
 Interim Report No. 1 includes
metrics defined as of January 31,
2011
 Additional metrics are being
considered


Flow-based indicator for ecosystem
health
Indicator to show unused but
allocated water, particularly for
tribal water
Metrics Resource
Categories
 Depletions
 Electrical Power
Resources
 Water Quality
 Flood Control
 Recreational
Resources
 Ecological
Resources
Study Phases and Tasks
Phase 1:
Water Supply
Assessment
Phase 2:
Water Demand
Assessment
Phase 3:
System Reliability
Analysis
Phase 4:
Development &
Evaluation of
Opportunities
1.1 – Select
Methods to
Estimate Current
Supply
2.1 – Select Methods
to Estimate Current
Demand
3.1 – Identify
Reliability Metrics
4.1 – Develop
Opportunities
1.2 – Select
Methods to Project
Future Supply
Formulate
Approach
to Include
Uncertainty
1.3 – Conduct
Assessment of
Current Supply
1.4 – Conduct
Assessment of
Future Supply
Develop
Future
Supply and
Demand
Scenarios
2.2 – Select Methods
to Project Future
Demand
3.2 – Estimate
Baseline System
Reliability
2.3 – Conduct
Assessment of
Current Demand
3.3 – Project Future
System Reliability
2.4 – Conduct
Assessment of
Future Demand
3.3.5-3.3.8 – Project
Future Reliability with
Opportunities
Yellow denotes current and future steps..
4.2 –
Evaluate and Refine
Opportunities
4.3 –
Finalize Opportunities
Milestones & Updated Study Timeline
February – August 2011
Quantify Demand Scenarios
August – November 2011
Perform “Baseline” System Reliability
Analysis
September – December 2011
Develop Options & Strategies
October 2011
Publish Interim Report No. 2
November 2011 – February 2012
Perform System Reliability Analysis with
Options & Strategies
March 2012
Publish Interim Report No. 3
April – May 2012
Finalize & Evaluate Options & Strategies
June 2012
Publish Draft Final Study Report
July 2012
Publish Final Study Report
Colorado River Basin Water Supply
and Demand Study
Study Contact Information
• Website: http://www.usbr.gov/lc/region/programs/crbstudy.html
• Email: [email protected]
• Telephone: 702-293-8500; Fax: 702-293-8148
•Ted Kowalski, Colorado Water Conservation Board
•Telephone: 303-866-3441, Ext. 3220
•Email: [email protected]