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Groundwater

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Quasi-fractal structure of watersheds�leads to downstream effects

Left panel shows a stream network colored and labeled according to stream order. Dashed grey, dashed black and solid black lines indicate watershed boundaries. Right panel shows entire Mississippi River watershed (green) with the Missouri River watershed (orange) nested within it.

https://serc.carleton.edu/integrate/teaching_materials/water_science_society/student_materials/861�Source: Images Patrick Belmont

First order (can be seasonal)

Second order (1+1=2)

3rd order (2+2=3!)

4th order (3+3=4!)

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Watersheds of California

https://watermanagement.ucdavis.edu/cooperative-extension/cwvt

California Water Virtual Tour

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Water cycle and storage

Dogrul et al. 2016

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Water recharge and storage

https://mavensnotebook.com/2013/09/03/mavens-minutes-water-storage-part-2-how-groundwater-banking-is-done-a-look-at-three-successful-operations/

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Where does your water come from?

Where does it go?

Source: California Energy Commission, California's Water - Energy Relationship, Final Staff Report, Nov 2005

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Where does your water come from?

​

https://www.valleywater.org/where-your-water-comes-from

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Where does your water come from?

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http://alert.valleywater.org/rgi.php

40% groundwater

35% treated water

15% Yosemite water

5% recycled water

5% other local

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https://www.valleywater.org/your-water/where-your-water-comes-from/imported-water

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Dealing with water stress

  • Water storage behind dams
    • high costs, environmental impacts, and political issues across borders
  • Groundwater banking
    • replenishment of aquifers with treated wastewater and/or with runoff available during times of excess.
    • Costs of treating, impounding, and injecting the water
    • the perception that consumers will be drinking dirty water
  • “Gray" water (only partially treated) for irrigation of parks, landscaping, golf courses
  • Desalination
    • energy required to remove salts from seawater/saline aquifers
    • For water poor but hydrocarbon-rich countries, the economics may support desalination
  • Import or export water