Peak Water, Climate Change, and California Planning in an Uncertain World
1. Peak Water, Climate Change, and California
Planning in an Uncertain World
Dr. Peter Gleick
Pacific Institute, Oakland, California
2. Overview
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“Peak Water” - What does it mean?
California’s water: a quick glance
Climate changes are coming
New trends and thinking about solutions
New challenges: Planning in an uncertain
world
• Moving forward
6. Renewable or Non-Renewable?
• Non-renewable resources are “stock” limited.
• Renewable resources are “flow” limited.
• Water uniquely exhibits characteristics of
both: overall renewable but with some fixed,
isolated non-renewable stocks.
7. Peak Renewable Water
Total Renewable Supply
But, how much can we
actually use??
How much should we
actually use?
10. Overall Economic and Ecological Value
Peak “Ecological” Water
Amount of Water Appropriated by Humans
11. So, What Does Peak Water Mean?
• We’ll never “run out” of water overall. It is
(mostly) renewable.
• Where water is “non-renewable” we will run
into stock constraints.
• We will run up against “flow” limits that are a
combination of natural and economic
constraints.
• We are increasingly hitting (or exceeding)
peak “ecological” water limits.
• We have to change the way we plan for the
future.
13. Challenges for California water
• Droughts, floods, and limited water
availability (peak renewable)
• Overpumped aquifers (peak non-renewable)
• Water quality
• Collapsing Delta ecosystems and fisheries
(peak ecological water)
• Growing demands
• Long-term climate change
What does this all mean for planning?
14.
15.
16. California’s Population
160,000,000
CALIFORNIA
140,000,000
CA Dept. of Finance
Projections
120,000,000
High Series
Population
100,000,000
Middle Series
80,000,000
Low Series
60,000,000
40,000,000
20,000,000
0
1920
1940
1960
1980
Source: California Department of Finance, Demographic Research Unit
http://www.dof.ca.gov/Research/Research.asp
2000
2020
2040
2060
2080
2100
2120
17.
18.
19. Water Diversions from the Delta
Source: CA State Water Project reports and
US Bureau of Reclamation 2012 data
32. What Does Climate Change Mean for
Planning?
• Rising temperatures and extreme heat events.
• Disappearing snowpack and a change in water
availability, timing, and quality.
• Rising sea levels and dramatic changes in
coastal flooding risks.
• More extreme events: droughts and floods.
33. New Thinking about Water Solutions
• Rethink “supply”
– Conjunctive use, treated wastewater, innovative
transfers, desalination, rainwater harvesting
• Rethink “demand”
– Reduce waste and increase efficiency, rethink
economic priorities and choices
• Rethink “management”
– New institutions, improve existing
institutions, better water monitoring
39. Producing More Food and Fiber with
Less Water
• Efficient Irrigation Technology
– Changing irrigation technology
• Improved Irrigation Scheduling
– Using local climate and soil information to
schedule irrigation; and
• Regulated Deficit Irrigation
– applying RDI to appropriate lands and crops.
40. Irrigation Technology is
Improving, More Potential Remains
100%
Percent of Irrigated Acreage
80%
60%
Micro/Drip
Sprinkler
Flood
40%
20%
0%
Field Crops Vegetables
Orchards
Vineyards
All Crops
41. Final Thoughts About Planning
• Our assumptions that the past is a good guide
to the future are no longer valid.
• There are good scientific and analytical tools
for looking at future scenarios.
• There are strategies for reducing vulnerability
to “peak water” limits and to climate changes.
• But new thinking, open minds, new
approaches are needed for planners and policy
makers.
42. Dr. Peter H. Gleick
pgleick@pacinst.org
Pacific
Institute, Oakland, Californi
a
www.pacinst.org
www.worldwater.org