Climate Change and U'S' Water Resources

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Climate Change and U.S. Water Resources

• Heather Cooley
• Pacific Institute
• 2009 National Drinking Water Symposium
• Orlando, Florida
• October 13, 2009

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Overview of Talk

• Brief overview of climate change and impacts on
  water sector
• Changes in water availability and quality
• Changes in demand
• What the water sector can do about it
• Adaptation
• Mitigation

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Source R. Seager et al. Science. 2007.
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Extreme Events (Floods and Droughts)
Average
Dry
Wet
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Mid-Century Runoff
Source Milly et al. 2005
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Climate Change Will Change the Timing of Runoff
in Basins with Snowfall and Snowmelt
Gleick 1986
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Wastewater Treatment Plants at Risk

• 22 wastewater treatment plants
• 325 MGD

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Summary of Climate Change Impacts

• A hotter world.
• Less certainty in precipitation changes. Extreme
  events floods and droughts will become more
  frequent and severe.
• Dramatic changes in snowfall and snowmelt
  dynamics.
• Rising sea levels with impacts on coastal
  aquifers, delta ecosystems, and coastal
  infrastructure.
• Deterioration of water quality.

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Manage the Unavoidable and Avoid the Unmanageable

• Some impacts of climate change are unavoidable.
  Work to understand and adapt to these.
• Many water system operations have implications
  for greenhouse gas emissions. Work to reduce
  these.

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Greenhouse Gas Mitigation

• Improve energy efficiency of operations.
• Develop renewable energy systems, including
  combined heat and power.
• Evaluate energy implications of operations.

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Water Supply Use Disposal All Require Energy
Source and Transport
Treatment
Distribution
End Use
Energy
Wastewater Treatment
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Californias Water-Related Energy Use
20 of the states electricity and 33 of the
states non-electricity natural gas
Source Calculated based on data in California
Energy Commission 2005
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Conclusions

• Climate change will affect the supply of and
  demand for water resources.
• Water managers must begin adaptation planning
  now.
• Water managers must also reduce GHG emissions.

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Heather CooleyPacific Institutewww.pacinst.org

• Thank you!

654 13th Street, Preservation Park, Oakland,
California 94612, U.S.A. 510-251-1600
www.pacinst.org
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Methods for Integrating Climate Change into
Regional Water Supply Planning
Hypothetical Scenarios (changes in T, P, other
variables)
Climate Model (GCM) Scenarios (changes in T, P,
other variables)
Downscaling Models
Physical or Statistical Hydrological Models
(Runoff, soil moisture, water deliveries)
Financial or Economic or Reliability or Flood or
Reservoir Management Models