Got Water? How Buildings Can Help with the Global Water Crisis
As it stands, the Earth’s freshwater sources are shrinking. The UN projects that if trends continue, the world will face a 40% shortfall in water availability by 2030. According to the World Wildlife Fund, about 1.1 billion people lack access to water, and 2.7 billion people experience water scarcity for at least one month of the year. While most of the world’s population may have little experience with water shortages, we are trending in the wrong direction. Growing numbers of communities are being affected by a lack of access to fresh water.
By now, most of us are familiar with net zero Greenhouse Gas (GHG) emissions. It’s not a zero-emission strategy but rather a method of capturing and offsetting emissions to remove more GHGs from the atmosphere than we contribute. The idea is one of the principal elements of reducing the effects of climate change.
The same principles apply to water use. Water shortages are occurring more frequently, and the need to preserve water is becoming more urgent. Enter the Net Zero Water movement--a strategy for both commercial properties and residential.
What is a Net Zero Water Building?
Perhaps you’re thinking, “Water is a renewable resource. Why do we need to aim for net zero use?”
It’s true that water is a renewable resource, but this is only valid when the water is carefully treated. When water is contaminated with pollutants from industrial processes, it is often beyond reasonable to recover efficiently.
To meet the requirements of being a net zero water building, buildings need to match or exceed their total water use with water from alternative sources and water returned to the original source. The goal is to reduce the amount of water being taken from freshwater sources to net zero.
Total water = the water consumed by a building from all sources over a year.
Alternative water = the amount of water consumed by a building from sustainable water sources. This could be via rainwater collection, stormwater collection, greywater, reclaimed waste water, or other renewable sources.
Water returned = the water that is collected from building systems and returned to the original freshwater source.
To become a net zero water building, the following equation must be satisfied:
Alternative Water Use + Water Returned ≥ Total Water Use
Why Is It Important for Businesses to Reach Net Zero Water?
Businesses are at the forefront of global freshwater use. Agriculture and irrigation account for 70% of the world’s freshwater use, and industry accounts for 19% of global use. Household use falls at only 11%. This means businesses are responsible for consuming 89% of the world’s freshwater and thus bear a heavy responsibility in preserving and caring for the planet’s freshwater resources.
Many companies have recognized the inevitable and are getting ahead of the curve before legislation is enacted. British Petroleum is pledging to be water positive by 2035, meaning they return more water to natural sources than they remove. Facebook, which is headquartered in the increasingly water-scarce region of California, has pledged to be water positive by 2030. PepsiCo has also committed to being water positive by 2030.
Many large businesses like Microsoft, Coca-Cola, 3M, Starbucks, and Bayer have signed on to the Water Resilience Coalition organized by the UN Global Compact under the CEO Water Mandate. The coalition binds the signatory companies to be water positive by 2050, reaching measurable targets by 2030.
Where Have Net Zero Water Buildings Been Achieved?
As mentioned, many companies are pledging to reach net zero water use in the coming years. But some buildings are well ahead and have already achieved this designation.
The Eurobusiness office tower in Curitiba, Brazil, became the first building in the world to achieve LEED Zero Water Certification. The office building treats 100% of its wastewater on-site, the roof has a natural space for rainwater collection, and no chemicals are part of the treatment processes. They also reduced water use by optimizing their current systems. Efficient fixtures and fittings minimize potable water consumption and concurrently the amount of wastewater.
In the U.S., Microsoft is working towards having its entire Silicon Valley campus reach net zero water. They will harvest rainwater from the roofs of buildings, wastewater will be treated on-site, and stormwater will be retained and treated.
Our project, Big River Steel in Osceola, Arkansas, replaces more clean water per year into the Mississippi River than it pulls from the potable water supply, thanks to its innovative, on-site water treatment plant.
How Can Emerald Built Environments Help?
Here at Emerald Built Environments, we know it can be challenging to develop a net zero strategy. Understanding the nuances of each waste stream takes experience. Taking it one level deeper--to net zero water--requires even more specialization.
We are ready to fill these expertise gaps with experienced and specialized staff. We can help throughout an entire building lifecycle, from informing developers on efficient water use designs to auditing existing buildings.Even more importantly, we recognize that a business’s primary goals are often financial performance. We align all stakeholders to achieve mutually-beneficial results.