Whether we are brushing our teeth or watering our garden, recent studies have shown that most of us take access to clean water for granted. But, it doesn't take much thought before you quickly realize that without it, our modern way of life would quickly come to an end. It's critical that developers and urban planners around the world factor this into their blueprints.

Each year, The Atlantic hosts the Green Intelligence Forum, bringing together the world's leading authorities on energy and the environment to discuss issues at the forefront of sustainable thought. This year, I was honored to speak on a panel about creating the sustainable city of the future. My fellow panelists provided perspectives on the financial, socio-political and infrastructure barriers to sustainability and the creation of more "walkable" urban communities. These are communities in which people are far less dependent on their automobiles for getting to work, enjoying leisure activities and running errands. Such communities are not only more convenient, but they also reduce energy consumption and cut greenhouse gas emissions.

Water infrastructure in urban areas

Clearly we cannot discuss infrastructure, sustainability or energy without discussing water, both its transport and its treatment. Urban water infrastructure faces many challenges, including century-old systems, inadequate investment, increased stress on systems and ever-increasing treatment requirements due to emerging pollutants. This has created a pending crisis in water and wastewater service delivery and increased groundwater contamination.

According to the UN, urban populations are expected to rise 40 to 50 percent in the coming decades to 5 billion people and by 2025, two thirds of us will live in areas facing moderate to severe water shortages. Proper methods of treating water are critical in sustaining the water supply in urban areas.

Yet, urban population growth continues to outpace infrastructure investment. Many large cities still lack treatment plants, and some existing plants are unable to keep up with the number of people they are required to serve. These outdated water treatment systems are not just a problem in the developing world. The American Society of Civil Engineers gave the U.S. a grade of D- for our drinking water and wastewater infrastructure.

One of the biggest consequences of exploding population growth in urban areas is increased pollution and the growing cost of energy required to turn dirty water into clean water. Today, roughly 15-20 percent of energy costs for an average city are for moving and treating water. This represents the single largest portion of energy costs. And when we look at individual commercial and residential buildings, up to 50 percent of building operating costs can be related to water movement and heating — costs that are not efficiently recovered today. In addition, water-stressed areas are often energy challenged, complicating the issue.

Investing for water infrastructure

Governments across the world are being urged to increase spending to upgrade water infrastructure. However, public entities cannot take on this task alone. The private sector also has a responsibility to invest in reliable and effective technological solutions for water analysis, movement and treatment. There are many good technologies already available to address these issues. However, a gap remains between the technology we have and what is actually used, largely because of the gap between new technologies and old infrastructure, and the inherent risk of implementation.

Two key areas of focus for this technology are reuse and recovery. That's because there is a lot of untapped efficiency in the way cities deal with water. Up to half of all treated water that could be directed back to usage is lost. As I discussed at the Forum, we are treating all water to drinkable level for municipalities, yet just one percent of water treated in municipalities is used for drinking and cooking — the rest goes to things like lawn sprinklers and industrial use. We must challenge ourselves to think of a future system that is more point-of-use focused, rather than using the whole system for treating all water to such a high standard.

For instance, a generally known concept for energy efficient buildings is "Net Zero," where a building is designed, constructed and operated to require a greatly reduced quantity of energy to operate, resulting in no net emissions of greenhouse gases. We should consider expanding this concept to cover water usage, as well. With this type of system, all of the water is re-circulated and there is fresh water intake only to cover for water lost through evaporation. This fresh water could be initially used for drinking and cooking. The technology is available but is not implemented from a system point of view, in large part due to investment costs.

There is a general concern about rising investment costs, and to bring down costs we need to increase capacity. However, this will create even more challenges with respect to running facilities efficiently. We must search for ways to bend the normal linear relationship between investment cost and process capacity, while minimizing process variations that might cause hiccups in the system. One way to do this is to look for decentralized solutions in both water supply and wastewater treatment, such as point-of-supply treatment and quality testing to reach drinking and cooking standard. Bringing the final treatment of water closer to the end user could potentially allow for more biodegradable and sustainable treatment solutions.

Wastes through infrastructure

It is obvious that there is a huge "untapped" supply capacity being wasted throughout our infrastructure. There are many interesting opportunities to re-engineer water cycles for buildings, blocks and cities. However, risks need to be eliminated through controlled scale-up procedures. We have opportunities to create industrial approaches through the piloting of new technology in demo environments, where there are no stringent operational conditions. Without such an opportunity, we will continue to build our future entirely on existing infrastructure without any major changes in sustainability.

The following are some examples of technological solutions to how industry is helping to address community water needs from India and Australia to Qatar and Dubai:

• In India, large water transport pumps are helping turn arid land into farmland. In one of the largest irrigation projects in the world, these large vertical pumps are transporting water 155 miles, irrigating 175,000 acres of land to help feed India's growing population and economy.

• In Doha, Qatar, treated wastewater is soon to be reused for agricultural irrigation and landscaping. This water scarce country with a population of over 800,000 will save millions of gallons of potable water per year previously used for this same purpose.

• In Dubai, a reverse osmosis desalination plant takes water from the Arabian Gulf and turns seawater into water clean enough for municipal use, including drinking water. The project is in part a result of high performance standards set for delivering reliable and economical drinking water to the people of this region.

• Australia is experiencing a severe multi-year drought, and advanced water treatment products are helping Sydney Airport to treat and recycle stormwater runoff for non-potable uses like cooling towers, washing vehicles and landscape irrigation. This project is a great example of water recovery that saves the airport about 350 million liters of fresh water a year — enough water to fill 140 Olympic-sized swimming pools.

Economic benefits

When we talk about sustainable cities it's important to remember that this includes economic sustainability, too. Improvements to water infrastructure would also lead to economic benefits.

In the U.S., the American Water Works Association projects that spending just $10 billion on repairs and improvements to water mains, leaking pipes, water treatment plants, pumping stations and similar projects would create work for more than 400,000 Americans throughout the economy, including almost 90,000 direct construction jobs.

The U.S. Department of Commerce estimates that adding one new job in local water and sewer services creates 3.68 jobs in the national economy to support it. And the Sustainable Water Infrastructure Investment Act could create up to 57,000 jobs by converting a modest investment by the federal government into billions of dollars of necessary economic investment into the nation's aging water and sewage infrastructure.

To become more sustainable, cities must become more efficient in energy consumption, transportation and most important, in how they manage water — with an ultimate goal of achieving "Net Zero" consumption. Industry has a responsibility to continue to find ways to conserve and reuse water. We also must become more proactive in communicating about critical issues such as increasing investment in the water sector. Every municipality and community needs tailored solutions for the collection, distribution, testing and treatment of their water. Only by joining technologies with organizations throughout the water industry value chain will our dream of truly sustainable cities become a reality.

Dr. Johan Groen is the chief technology officer for Xylem Inc., a leading global water technology provider, enabling customers to transport, treat, test and efficiently use water in public utility, residential, commercial, agricultural and industrial settings. Launched in 2011 from the spinoff of the water-related businesses of ITT Corporation, Xylem is headquartered in White Plains, N.Y., with 2010 revenues of $3.2 billion and 12,000 employees worldwide.