Chapter 17: Freshwater Resources
Toilet to Tap: A California County is Tapping Controversial Sources for Drinking Water
Story Abstract and Additional Information
This chapter examines the fact that freshwater is a precious but limited resource, and is essential to life.
Some regions consume water faster than it is replenished. And unfortunately, water is not evenly
distributed across the globe; many people worldwide lack access to enough clean water. Methods are
available to recover and purify otherwise dirty water, but we also need to use water more wisely.
Here are some of the key points in the story for this chapter:
What are the sources of freshwater on Earth?

Even though Earth is covered in more than 1,400 million cubic kilometers of water—about 75%
of its surface—only about 1/100 of 1% of that water is usable by humans. Humans need liquid
freshwater (which has few dissolved ions such as salt); ocean water is too salty for human
consumption and is toxic in large doses. Complicating things, nearly 80% of the freshwater on
the planet is trapped in ice caps at the poles and glaciers around the world. Wherever there is
water, it is constantly moving through the environment via the water cycle (hydrologic cycle).
This process sends more than 66,000 cubic kilometers of water vapor into the atmosphere every
year, equivalent to 17,000 trillion gallons. Learn more from the U.S. Geological Survey (USGS)
about the water cycle and sources of freshwater at
http://ga.water.usgs.gov/edu/watercycle.html.

To help address water scarcity issues, Shivaji Deshmukh and other Orange County Water District
(OCWD) staff decided to create drinking water from wastewater. They developed the
Groundwater Replenishment System (GWRS), which takes former sewage water, cleans it up,
and then pumps it into underground drinking water sources. The GWS went online in 2008 and
is scheduled to be expanded by September 2014. Watch this video to get a tour of the GWS
facility: http://www.youtube.com/watch?v=B-vQzp3LxnA.
What are the causes and consequences of water scarcity?

Around the world, many areas suffer from water scarcity—not having access to enough clean
water supplies. In some dry regions, there is simply not enough to meet needs; many arid
nations like those of the Middle East, parts of Africa, and much of Australia face water shortages
as a way of life. According to the Water Stress Index, compiled by the risk-assessment analyst
firm Maplecroft, the Middle Eastern nations of Bahrain, Qatar, Kuwait, and Saudi Arabia are the
most water-stressed countries in the world, with the lowest per capita water availability. Learn
more about the Water Stress Index at http://maplecroft.com/about/news/water-stress.html.

The World Health Organization (WHO) estimates that 1 in 3 people—more than 2 billion—lack
sufficient access to clean water; even more lack access to sufficient sanitation facilities (safe
disposal of human waste). In developing nations where water and funding for basic sanitation
are scarce, people use nearby surface waters to meet their basic cooking, drinking, and washing
needs. These waters can be contaminated with raw sewage, which increases the chance for
disease transmission. As populations increase, so will scarcity and sanitation issues; according to
the United Nations, 2 out of 3 people will face water shortages by 2025. Read ten facts about
water scarcity from WHO:
http://www.who.int/features/factfiles/water/water_facts/en/index.html.
How can conservation help us address water scarcity issues?

The biggest drain on freshwater supplies isn’t the water used to shower, flush the toilet, and
wash dishes. In the United States, about 70% of all freshwater withdrawals, from surface or
groundwater sources, goes to agriculture. Read more from the California Agricultural Water
Stewardship Initiative about farmers' efforts to address water scarcity issues:
http://agwaterstewards.org/.

Industry is the next biggest consumer of water. For the average individual in a developed nation,
reducing waste is tied to reducing consumption, not just of water but of industrial and
agricultural products as well. It may be surprising just how much water goes into some of the
products you use. Read more about how water is used for agriculture and industry and about
efforts to reduce water consumption: http://discovermagazine.com/2008/jun/28-everythingyou-know-about-water-conservation-is-wrong.
Additional information about other topics from this chapter:
Energy Star

You can contribute to water conservation by using new water-efficient technologies and by
making behavioral changes that don't waste water. Energy Star is a program run by the
Environmental Protection Agency and the Department of Energy to help provide energyefficient products and practices. Learn how a product such as a dishwasher or washing machine
earns the Energy Star label: http://www.energystar.gov/index.cfm?c=products.pr_how_earn.