“We forget that the water cycle and the life cycle are one.” – Jacques Cousteau

Water does more than just quench our thirst. It is the foundation of our way of life. And all water originates in wild nature and its life-giving services. So where does water come from exactly?  More importantly, exactly how much do we need to survive? And why is abundant, clean, fresh water available only to some people and not to all?

Many people assume that because water covers over 70% of the planet it is infinitely abundant. But most of that is saltwater. The amount of freshwater available for drinking and irrigating our crops makes up only about 1% of Earth’s surface. This tiny percent must be split up across the world’s 7.5 billion people, our agricultural lands, and the wildlife that depend on it to survive.

According to the UN, the average person needs between 20 and 50 liters (5.3-13.2 gallons) of water each day to satisfy their drinking, cooking, cleaning, and sanitation needs. Having access to clean water is the difference between living in poverty or not. A report from UNICEF says that a lack of access to clean water causes waterborne illnesses that kill more than 1.6 million young children each year. In the rest of this article we take a look at a couple of cities to compare how  developed and developing economies differ in access and utilization of water.

Las Vegas:

Wealthier cities can afford to live beyond their water means, even if it hurts surrounding ecology.

Developed world cities are seemingly wealthy enough to disconnect from wild nature’s water cycle, at least in the short-term. And there is no greater example of a city’s ability to buy its way out of its own ecology than Las Vegas.. Well-known as an oasis situated in the middle of a barren desert, Las Vegas manages to collect and propel millions (approximately 489 million) of gallons of water daily to its inhabitants.

• Population and usage: The metro region of Vegas has a population of 2.2 million, the average household uses 222 gallons (840 liters) of water per day. This is slightly below the EPA’s reported average of over 300 gallons (1135 liters) per household in the total United States. Keep in mind this doesn’t account for water use beyond households, like entertainment, irrigation, etc.
  Where does the water come from? The Colorado River/Lake Mead and groundwater. The natural areas have suffered immensely from climate change and from population reliance on these water sources. The Colorado River is facing a severe drought and Lake Mead which is fed by the Colorado has dropped 130 feet since 2000.
  In 1989, the Southern Nevada Water Authority attempted to purchase water rights that would create a 300 mile long pipeline to transfer water to the city of Las Vegas. The environmental impacts would have been devastating and affected parks like Great Basin National Park and several National Wildlife Refuges. Fortunately, this project has been indefinitely deferred.
• What is Vegas doing about their potential water crisis? Fortunately, the response to increased population and increasing demand for water has been met with various water restrictions. The water authorities have set in place many restrictions to conserve water use. This includes watering days for landscapes, fines for not fixing leaks within 48 hours, and other strategies. The city is even attempting to ban grass that isn’t utilized for walking or some other purpose besides ornamental.

São Paulo:

When nature teaches you a lesson, the second lesson should no longer be a warning.

Unlike Las Vegas, São Paulo has faced the urgency of running out of water and what that reality looks like during the impending doom of day zero. Sao Paulo was able to avert this crisis (for the most part) but is now suffering from another potential shortage. This time due to deforestation. Cutting the forest reduces its capacity to release humidity into the air, diminishing rainfall in southeast Brazil, according to a recent study by one of the country’s leading climate scientists. This also means less filtration and higher pollution in water.

• Wealth makes a difference in the ability to access clean water: In 2015, the fast approaching day zero was especially hard on poorer neighborhoods. These settlements are often located on higher terrain which requires higher water pressure to reach or have faulty piping. Wealthier citizens can avoid water shortages by purchasing personal tanks and acquire water from private buyers.
• Where does São Paulo get its water? Brazil holds between 12 to 14% of the world’s freshwater supply, and 70% of flows through the Amazon River basin. São Paulo is Brazil’s largest city and receives only 1.6% of that water supply. SãoPaulo receives its water from the Cantareira reservoirs and the Guarapiranga and Billings reservoirs. All reservoirs are running at a low capacity. The Cantareira due to deforestation and the others due to poor infrastructure and heavy pollution.
• How did São Paulo escape the water crisis of day zero? The effects still stand today, but the city did something that saved them some time- they got people to use less water. They did this by initially rewarding low usage and then began fining people for their higher water usage. The daily water use per person dropped from 155 liters(40 gallons)/person/day in February 2014 to 118 (31 gallons) in March 2015.

Tokyo:

A city that relies on the consistent supply of surface water, climate change prevention should be of top priority.

Tokyo is currently the largest city in the world with a population of 38 million people. Based on a survey by the Bureau of Waterworks in the Tokyo Metropolitan Government, average water use per person is about 230 liters(60 gallons) per day. With so many inhabitants in one place, pressure is high on city officials in a variety of areas to deliver basic necessities, water being one of the biggest. Climate change impacts have resulted in droughts, and Tsunamis, and sea level rise causing saltwater intrusion to aquifers. With a city this populated, small impacts can cause huge problems in a short amount of time.

• Water shortage and the 1965 Olympics: With a much smaller population of 10.6 million people in 1965, Tokyo suffered from a severe water shortage due to a limited rainy season and increased demands for the upcoming Olympics. Before October 1961 through March of 1965, Tokyo was forced to restrict its water supply for 42 months.
• Where does the water come from? Tokyo mostly gets its water from surface areas like rivers, lakes, rainfall, and distant snowpack. The remaining amount is collected from underground aquifers and wells. Tokyo experiences a drought once every decade but studies show that this will increase with the effects of climate change.
• Water storage and conservation efforts. Just because you have plenty of rain doesn’t mean it reaches everyone. Japan has four months out of the year that deliver monsoons and typhoons, however, due to Japan’s changing landscape this water doesn’t reach every city. Tokyo can fall into a water crisis very easily with such a large population and great reliance on the weather to deliver their water needs. Having experienced shortages in the past, Tokyo implements other solutions to avoid a water shortage like turning rooftops into rain catchments, and having an efficient response time to pipe leakage. Tokyo’s measures to avoid leaks have even resulted in curbing CO2 emissions.

Mumbai:

Water comes from nature, but increasing demands on ecosystems that produce water jeopardizes human quality of life

Mumbai is India’s largest city with 12.48 million people as of 2011, 6.5 million of these people live in slums. The demand for water is 3.9 million liters (1 million gallons) per day. Having access to potable water greatly depends on the neighborhood you live in or your ability to purchase water privately or prepackaged. Water quality has a huge impact on humans and nature. With Mumbai’s current pollution problems, water quality is degraded and threatens the health of humans and ecosystems.

• How is water distributed amongst non-slums and slums? As of 2015, non-slums receive 150 liters (40 gallons) per day while slums receive a meager amount of 45 liters (11 gallons) per day. According to one intensive study, some slums don’t always receive the allotted water and 50% of the time the water was tested it showed contamination. Slum dwellers often have to rely on informal distribution methods like purchasing from neighbors who have taps or prepackaged water. This also means they often pay a higher rate for water than the average.
• Where does Mumbai get its water from? Mumbai gets its water supply from seven lakes and dams- Tulsi, Vehar, Middle Vaitarna, Upper Vaitarna, Bhatsa, Modak Sagar and Tansa Lakes. The dams currently deliver 3.4 billion liters (990,645,196 gallons) of water daily.
• Desalination projects under way to combat climate change and increased water demands: Mumbai is facing increased needs as population continues to increase and climate change affects weather patterns. The seven reservoirs rely on rainfall for their water supply and even short term changes can have heavy effects on Mumbai residents. The plant is projected to take a little over two years to build and could hold up to 200 million liters (52.8 million gallons) of water with potential for expansion. Attention from this project has led experts to ask why emphasis isn’t being placed on water conservation methods and repairs/improvements to pipelines.

All cities face the common problem of supply and demand. With increasing population sizes and effects of climate change, pollution, deforestation, every city is searching and testing solutions to keep water flowing.

One of the best solutions to help increase abundance and quality of one of nature’s greatest resources, is to implement nature based solutions- planting more forest for natural water filtration, erosion prevention, preventing deforestation. When helping nature nurture nature, in the end we set ourselves up for less disaster, less destruction and pollution to ecosystems, and a healthier planet with clean water more accessible to all.  Check out the water facts on your city to learn more about your water supply and how it affects surrounding ecosystems.