Published on IDRA Global Connections Spring 2020 Issue
By Dr. Matthew Ries
Sustainability. It’s a concept few would argue with, but not many can define. Often affiliated with environmental, or “green” benefits, true sustainability is a balance of components of the triple bottom line which includes not only the traditional economic bottom line, but also accounts for less-traditional environmental and social bottom lines, or impacts. Sustainability describes an approach where decisions made today will not compromise future generations. Inherently, it requires a long-term view. In the water sector, where some infrastructure can last for decades or centuries, and planning decisions impact multiple generations, sustainability should be a guiding principle for water managers.
DC Water distributes drinking water and collects and treats wastewater for the 700,000 residents and 17.8 million annual visitors in the District of Columbia (DC), the capital city of the United States. DC Water also provides wholesale wastewater treatment services for an additional 1.6 million people in neighboring states. We utilize cutting-edge technology at Blue Plains, the world’s largest advanced wastewater treatment plant, treating over 300 million gallons per day, while at the same time relying on water supply infrastructure, some of which was built in the 1850s, which still serves us well today.
Over the past decade, DC Water has researched, designed, and implemented projects that contribute to a more sustainable utility. At Blue Plains, we operate the first CAMBI® thermal hydrolysis process in North America and the largest in the world. This process reduced biosolids production and hauling costs by over 50% and creates Bloom®, a soil conditioner rich in organic material and nutrients. We are pilot testing green infrastructure to replace an underground, gray infrastructure tunnel and capture rainwater to reduce combined sewer overflows. This green infrastructure is being financed by a “green bond” that pays a variable rate to investors depending on system performance. Our new headquarters building is designed to a LEED® Platinum Class A rating and includes features such as passive solar heating; sewer energy recovery for heat and cooling exchange for the building; and rainwater capture for non-potable uses.
While these sustainable practices demonstrate sector leadership and generate goodwill with stakeholders, it remains a challenge to keep a focus on a long-term horizon. DC Water, like every water utility, has acute, shortterm challenges to address. Our aging pipes, with a median age of 79 and 90 years for water and wastewater, respectively, require constant vigilance and frequent emergency repair. Regulatory mandates require massive, unfunded infrastructure investments, all of which has led to ratepayer affordability challenges for some in our community. Furthermore, humans are hard-wired with a “present bias,” the tendency to place more value on short-term returns than long-term consequences with all types of decisions, making sustainable thinking an inherent challenge in all aspects of our lives. Over the past decade, DC Water has researched, designed, and implemented projects that contribute to a more sustainable utility.
Recent research of U.S. urban water utility leaders exposed further barriers to adopting sustainability measures. This included a lack of: (1) an agreed-to definition of sustainability for the water sector; (2) an incentive, because the vast majority of US utilities are public utilities that essentially operate as a monopoly; and (3) resources to dedicate to sustainability initiatives. When asked what might drive adoption of sustainability measures, these same leaders noted that public demand, political will, and the right tools were needed. These responses provide insight into opportunities to push forward.
Increasingly, cities and local leaders are picking up the mantle of resiliency in the face of a changing climate manifested in both droughts and floods; increasing storm intensity; and sea level rise, as examples. Public awareness of these issues and their impacts on daily lives are increasing. This awareness of accelerating change provides the public and political push to prioritize and implement more sustainable approaches. Sustainable rating systems like LEED® and Envision provide guidance and recognition for sustainable projects, and water utilities and associations are increasingly linking to the UN’s Sustainable Development Goals. Given the different circumstances of water utilities, a variety of sustainability approaches are needed.
Sustainability, while abstract, it essential. Sustainable water management is inextricably linked to enabling society’s sustainability. Increasingly, our ratepayers demand it, and a new generation coming into our workforce is helping to lead the charge. As water managers, we owe it to our communities and our future generations to think sustainably, making decisions now that will positively impact future generations and help provide our crucial services today, and over the long-term.