What have toilets got to do with climate change? As we mark World Toilet Day (November 19), with this year’s theme of sustainable sanitation and climate change, this is a question that many organizations are answering. For the 50L Home Coalition it’s about toilets and the systems they connect to: how they can be an important part of responsible household water consumption and respond to climate change impacts that exacerbate urban water shortages.
In many regions, toilets are the main source of water use in the home. In the United States, for example, toilets account for nearly 30 percent of an average home’s indoor water consumption. Reducing water use for toilets will be a key component of achieving a 50L Home — down from a daily per capita water consumption that can be as high as 500L per day. To address this, there have been several innovative technologies, regulations, and consumer campaigns over the last decade or so that aim to reduce or remove the need for water in toilet use.
For example, water efficiency product labelling plays an important role in raising awareness and educating consumers. A recent study highlighted that many well-established labels deliver quantifiable water and energy savings as well as reduce customer bills. The WaterSense label, an output of a voluntary partnership program sponsored by the U.S. Environmental Protection Agency (EPA), illustrates that if inefficient toilets in the United States were replaced with WaterSense labelled models, there could be a saving of 360 billion gallons (or 1.6 billon m3) of water per year.
From a technology perspective, the Bill & Melinda Gates Foundation have been instrumental in catalyzing innovation through their Reinventing the Toilet challenge, which has led to the commercialization of a number of no- to low-water toilets in developed and developing countries. And considering that today, 4.2 billion people are living without access to safely managed sanitation, we must ensure that urban systems are designed to meet these basic needs and at the same time reduce dependencies on drinking-water-quality water.
While these approaches to reducing and removing the need for water have led to incremental reductions in household water consumption, it is reuse in the home that offers transformational opportunities. A recently published paper from research funded by the Gates Foundation demonstrated the effectiveness of technologies to recycle water from hand washing and toilet flush water in real-life applications. As is often the case, although the technology is effective, there are broader systemic issues that need to be addressed for widescale deployment. These are the kind of issues that the 50L Home Coalition is tackling. In thinking through toilets in a 50L Home, there are several critical perspectives to look at:
- With lower flows into and out of homes, what is the impact of low- or no-water toilets on existing centralized urban water supply and sewerage systems?
- What are the key value drivers for consumer behavior change for widespread adoption of toilets that reuse water?
- What is required in terms of standards, regulations, norms, and product labelling for reusing water in the home?
- How to incentivize real estate developers and investors to adopt 50L Home concepts in construction projects?
- How do we connect and reuse water across the home: laundry, bathroom and kitchen?
Responding to these questions requires unusual partnerships, new thinking and pilot testing, all things that the 50L Home Coalition aims to facilitate. It is unacceptable that 2/3 of the global population does not have access to safely managed sanitation, and we echo calls made by world leaders to prioritize water, sanitation and hygiene interventions. As we build the next generation of urban sanitation systems, lets create homes that make 50L of water feel like 500L of water.