Download + 2.25 o C No adaptation - University of Washington

Overview of Water Resources
Planning and Management
Dr. Alan F. Hamlet
•JISAO/CSES Climate Impacts Group
•Dept. of Civil and Environmental Engineering
University of Washington
Water Resources Management is
an Ancient Human Activity
•Nomadic behavior
•Use of springs and wells in shallow ground water near
settlements
•By about 300 AD, Rome had nine aquaducts feeding the
city, totaling more 400 km in length. There were
substantial dams, and use of hydropower (water wheels)
appears to have been common.
•Starting around 600 AD, the flow in the Nile was
measured as means to forecasting water supply and
potential harvest.
Roman Flour Mill at Barbégal (present day France) ~400 AD
Schematic of Dijon Public Fountain (~1850)
By the mid-19th century, extensive engineering works to
provide water supply had been constructed in some
cities. These systems were very similar in many ways to
modern systems with the exception of the distribution and
water treatment systems. A famous example in Europe is
the Dijon water supply system developed by Henry Darcy.
Darcy also estimated water demand (about 35 gallons per
person per day for domestic use, street sanitation).
From the late 19th century to the early 20th century, as
populations increased, water resources development
reached unprecedented levels in the developed world.
In the
United States alone, there are currently more than
I
8100
n major dams.
Hoover Dam
Water Resources is Linked to a Huge Number of
Important Management and Socioeconomic Issues
•Water supply
•Food security
•Human health
•Ecosystem health and sustainability
•Economic development
•Energy production and energy use
•Transportation (navigation)
•Flooding and storm water management
•Recreation
•Drought impacts
•Social equity and social justice
•Education
•Interstate and international relations
•Urban development and planning
•Industrial development
•Water quality
•Fire prevention
Since the mid 1970s in the U.S. the basic elements of
water resources planning have extended dramatically.
Evolution of Columbia Basin Integration Boundaries
Altered hydrologic response
Creation of Lake systems in upper basin
Displacement of people
Beginning of major salmon impacts
US Endangered Species Listings for Salmon
Kootenay sturgeon threatened
Columbia Basin Trust
1995 Biological Opinion
Proposals for dam removal
Columbia R. Treaty
Flood Control
Hydro
Climate variability and change
Aboriginal concerns
Additional US ESA listings
Transboundary issues
Privatization of hydro
~1965
~1975
~1990
~2000
Some Challenges for Water Management in the 21st Century
•Growing human populations
•Degradation of watersheds due to urbanization, etc.
•Linkages between groundwater and surface water
•Limited opportunities for infrastructure expansion
•Increasing need to address ecosystem impacts and water quality
•Complexity of multi-objective systems
•Outdated planning and management paradigms (build it and leave it)
•Climate Change
Understanding
Planning as a Process
The primary objective of water
resources planning is to create
functionally robust and beneficial
water resources management
systems
Water resources planning takes many forms and has many
variations, and is perhaps best viewed as a process rather
than a set of specific outcomes, because the specifics will vary
so widely from case to case.
The US Army Corps of Engineers, in their nicely written
overview of the water resources planning, describe the
planning process as an iterative sequence framed by six steps:
•Identify Problems and Opportunities
•Take Inventory and Forecast Resources
•Formulate Alternative Plans
•Evaluate Alternative Plans
•Compare Alternative Plans
•Select Preferred Alternatives
Planning is an Iterative Process:
Information acquired in the later steps of the sequence may
identify key missing pieces in earlier steps which need to be
addressed.
For example, in the process of forecasting current and future
resources, additional problems or opportunities may emerge
that were not originally identified.
Although useful as an introduction, the framework in the
USACE planning manual is very generic, and it is often
necessary to use case studies to gain some insight into how
these techniques would actually be applied.
Some Extreme Examples in Current Events:
New Orleans
Atlanta
Colorado River Basin
Water Resources Planning Research
Climatological Foundation of U.S. Water
Resources Planning and Management:
1) Risks are stationary in time.
2) Observed streamflow records are the best estimate of
future variability.
3) Systems and operational paradigms that are robust to
past variability are robust to future variability.
Schematic of a Typical
Water Planning Framework
Observed Streamflows
Planning Models
System Drivers
Annual streamflow reconstructions at The Dalles, OR
using tree ring growth indices derived from douglas-fir
and limber pine from SE British Columbia - Kamloops to
Banff/Jasper (1750-1964)
350000
Columbia Basin
Planning Window
300000
Observed Annual
Streamflow
Observed 5 yr mean
200000
Reconstructed Annual
Streamflow
Linear (Reconstructed
Annual Streamflow)
150000
100000
y = -22.831x + 214682
50000
1975
1950
1925
1900
1875
1850
1825
1800
1775
0
1750
Flow (cfs)
250000
16.4 MAF was considered a conservative estimate at the time of
the Compact. However, the average annual flow over the 20th
century has been only 15 MAF.
Relative to the gage record today, flows in the early 20th century appear to
be unusually high. How unusual is this period in a longer-term context?
(Figure Courtesy Connie Woodhouse)
Tree rings placed the gage record in a long-term
context
Colorado
River flow,
reconstructed
by Stockton
and Jacoby,
1976
Stockton and Jacoby 1976
“…the timing of the drafting of the Compact was
an unfortunate event, in that it did not occur during
a representative flow period.”
“The general picture of a collision between water
demand and supply in the UCRB in the not-toodistant future is all too apparent.”
Stockton and Jacoby 1976
(Figure Courtesy Connie Woodhouse)
What’s the Problem?
Despite a general awareness of these issues in the water
planning community, there is growing evidence that future
climate variability will not look like the past and that current
planning activities, which frequently use a limited observed
streamflow record to represent climate variability, are in
danger of repeating the same kind of mistakes made more
than 80 years ago in forging the Colorado River Compact.
Long-term planning and specific agreements influenced by
this planning (such as long-term water allocation agreements)
should be informed by the best and most complete climate
information available, but frequently they are not.
The Myth of Stationarity Meets the
Death of Stationarity
Muir Glacier in Alaska
Aug, 13, 1941
Aug, 31, 2004
Image Credit: National Snow and Ice Data Center, W. O. Field, B. F. Molnia
http://nsidc.org/data/glacier_photo/special_high_res.html
Simulated Changes in Natural Runoff Timing in the Naches
River Basin Associated with 2 C Warming
120
Simulated Basin Avg Runoff (mm)
100
80
Impacts:
•Increased winter flow
•Earlier and reduced peak flows
•Reduced summer flow volume
•Reduced late summer low flow
1950
60
plus2c
40
20
0
oct
nov
dec
jan
feb
mar
apr
may
jun
jul
aug
sep
2000
1996
1992
1988
1984
1980
1976
1972
1968
1964
1960
1956
1952
1948
1944
1940
CRB
1936
CA
1932
1928
3
1924
1920
1916
Std Anomalies Relative to 1961-1990
Regionally Averaged Cool Season Precipitation Anomalies
4
PNW
PRECIP
GB
2
1
0
-1
-2
-3
Changes in Simulated April 1
Snowpack for the Canadian
and U.S. portions of the
Columbia River basin
(% change relative to current climate)
20th Century Climate
“2040s” (+1.7 C)
-3.6%
-21.4%
April 1 SWE (mm)
“2060s” (+ 2.25 C)
-11.5%
-34.8%
Rebalancing Water Systems in
Response to Climate Change
Some Conflicting Objectives Likely to be Impacted by
Climate Change:
•Hydropower and water supply vs. flood control
•Hydropower and water supply vs. instream flow and
ecosystem services.
•Interstate and international transboundary agreements
8000
7000
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Sep
Full
25000
20000
15000
: Current Climate
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Aug
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Apr
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Nov
10000
Oct
Storage
Jul
Aug
Jun
Apr
May
Mar
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30000
Nov
Reservoir Inflow
Flood Control vs. Refill
Flood Control vs. Refill
Streamflow timing shifts can reduce the reliability of reservoir refill
8000
+ 2.25 oC
6000
5000
4000
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30000
Full
2000
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25000
20000
15000
: Current Climate
Sep
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May
Apr
Mar
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Dec
10000
Nov
: + 2.25 oC No adaptation
Oct
Storage
Sep
Jul
Aug
Jun
Apr
May
Mar
Jan
Feb
Dec
Oct
0
Nov
Reservoir Inflow
7000
Flood Control vs. Refill
Streamflow timing shifts can reduce the reliability of reservoir refill
8000
7000
+ 2.25 oC
5000
4000
30000
3000
Full
2000
1000
: Current Climate
Storage
Aug
25000
Sep
Jul
Jun
Apr
May
Mar
Jan
Feb
Dec
Oct
0
Nov
20000
: + 2.25 oC No adaption
15000
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
Dec
10000
Nov
: + 2.25 oC plus adaption
Oct
Reservoir Inflow
6000
Major U.S. Flood Control Checkpoints
Bonners Ferry
Columbia Falls
The Dalles
Optimization Reduces Storage Deficits without Jeopardizing Flood Protection
2,000
Storage Deficits
1,500
optimized
1,000
500
Duncan
Libby
Mica
Hungry
Horse
Dworshak
Climate change/no adaptation
600
Flood Risks
Flow at The Dalles (kcfs)
Grand
Coulee
0
Arrow
July 31 Average Storage Deficit (KAF)
Climate change/no adaptation
500
400
300
optimized
200
100
-2
-1
0
1
2
3
Extreme Value Type I Distribution Reduced Variate, Y
4
5
Adaptation Strategies
Overview of Water Resources Adaptation
Challenges:
•Hydroclimatology
•Systems Engineering and Water Resources
Engineering Design
•Institutional Considerations
•Politics
Approaches to Adaptation and Planning
•Anticipate changes. Accept that the future climate will be
substantially different than the past.
•Use scenario based planning to evaluate options rather
than the historic record.
•Expect surprises and plan for flexibility and robustness in
the face of uncertain changes rather than counting on one
approach.
•Plan for the long haul. Where possible, make adaptive
responses and agreements “self tending” to avoid repetitive
costs of intervention as impacts increase over time.
Schematic of Climate Change
Water Planning Framework
Observed Streamflows
Planning Models
Altered Streamflows
Climate Change Scenarios
System Drivers
Example of a Flexible, Self-Tending Reservoir
Operating System
•Improved Streamflow Forecasts Incorporating Warming and
Other Features of Altered Climate System
•Dynamic Reservoir Operating Systems Using Optimization or
Hybrid Optimization/Simulation Approaches to Rebalance the
System.
•Such systems are more flexible and adaptable because they do not
require a “trigger” for a change in the operating policies, and arguably do
not require as much intervention as the climate system gradually changes,
because the system responds autonomously to improvements in forecasts
(whether related to climate change or other scientific advances)
•These ideas are not really new:
Harvard Water Program ~1965