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Peter Gleick: The Real Cost of Water We Use

Lecture notes

World water crisis
failure to meet basic human needs for water
we have knowledge of how to provide clean water and sanitation
have failded to do so for large percentage of Earth’s population

1.5-2 million preventable deaths per year

scarcity/resource depleation

arid regions
northern Africa
persian gulf

water quality
we contaminate fresh water
human waste
industrial waste

climate change
humans are changing climate at rates much faster than natural rates
will impact natural hydrologic cycle and water distribution systems

will affect water availability, quality, etc.

Human uses of water
food production
irrigated agriculture (40% of world’s food)

all water comes out of natural ecosystems
humans move water across ecosystems.
i.e. out of natural water shed area
divert rivers
affecting species, causing extinction

ecosystems cross borders.
Colorado river basin
shared by seven states and Mexico
legal agreements, compacts, and treatee
Nile is shared by ten nations
Egypt, etc
Danube is shared by eighteen nations

water, politics, conflict

Peak water
exponential growth has a tendency to get out of hand
population growth
economic growth (GNP)
CO2 concentration in atmosphere (greenhouse gasses)

peaking curve
exponential at first
peaks at some point
falls thereafter
may recover, or stabilize

peak oil
fishery population

‘s’ curve
slow growth at first
then exponential
peaks and levels off

some resources are non-renewable
oil (renewal process slower than is useful for humans, consumption outpaces)

water is, basically renewable
flow limited – hydrologic cycle
cannot use more than natural flow provides
e.g. Colorado river does not complete its natural course to the Gulf of California
e.g. solar energy – sun provides steady stream of energy

non-renewable stocks of water
fossil water
e.g. ogalala aquifer
pumping faster than renewal process (slow geologic process)
as much as 40% of food grown worldwide is grown using fossil water

transportation costs
water is not profitable to move via tanker, as oil has proven
we don’t move water around too much
some large scale water infrastructure exists
California central valley

bottled water
1,000 times more expensive than tap
economically feasable to bottle and distribute water

Book — Bottled and Sold: The Story Behind Our Obsession with Bottled Water by Peter H. Gleick

there is no known substitute for water, for most things
e.g. growing food, human life

We build infrastructure to store and use the total flow of renewable water

How much peak renewable should we use?

Peak non-renewable water
depletion of fossil water
farmers are shifting back to dry ground farming techniques as water becomes more costly to pump

The more water we use, the more economic benefit we get
essentially linear process

The more water we use, the less ecological value remains intact

Inverse curves, produce a point of optimal use

Peak water
Non renewable water creates stock constraints
Renewable water sources create flow limits
Ecological limitations become more present

Move to sustainable water management and useful

Develop new supply
Traditionally: more drilling, dam building, aquaduct, etc.
we are running into constraints on traditional supply
no more dams or aquifers that make economic sense (in U.S.)
other places in world need traditional infrastructure — built to different standards
consider economic, ecological, social, and cultural costs

Treated wastewater
asset, not liability
use highly treated wastewater in appropriate areas

expensive but reliable

rainwater harvesting

groundwater/surface water together
recharge groundwater aquifers

maintain to a better level, existing water infrastructure

improve efficiency of water use
we are not at the limits of efficiency
we are often at the end of available water supply

improve/enforce standards for water quality

use economics, water is an economic good
true valuation, pricing questions, equity issues
price/meter water properly
balance economics with human rights

improve/expand public participation in decision making

improve water institutions
21st century revitalization

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