ASCE MOP 137
SUSTAINABILITY AND ENERGY MANAGEMENT FOR WATER RESOURCE RECOVERY FACILITIES
|Publication Date:||1 January 2018|
Energy savings and sustainable design deserve special attention to be sure water resource recovery facilities (WRRFs) have long-term adaptability and resilience to global climate change, volatile energy prices, and other predictable change scenarios. Municipal WRRFs in the United States use approximately 30.2 bil. kWh/yr, or approximately 0.8% of total electricity use in the United States (EPRI, 2013). Yet, of the approximately 14,780 WRRFs in the United States, only approximately 1268 (8.4%) include anaerobic digestion (which offers the potential to recovery chemical energy) and beneficially use this energy on site for production of power and/or heat (WEF, 2013).
The umbrella of sustainability covers long-term provisions for resilient facilities to manage a wider range of stressors, and treatment process adaptability to accommodate changing regulations. Sustainability in this context refers to the ability to continue operating without causing immediate or long-term harm to the environment, society, or depleting natural resources. In the accounting sense, this means planning for the future by making annual financial investments that seek to minimize the total life cycle cost of a WRRF across its full life and avoid deferring costs and negative effects to future generations. The concept of sustainability has also expanded to include indirect effects to the greater community, and consider local industry partnerships and social justice issues. Optimizing the sustainability of a WRRF requires systems thinking and a willingness to make change. Using strong leadership, cultural buy-in, and an understanding of the best technical practices described in this publication, utility managers can make a big difference.
Public expectations of today's wastewater utility have changed in recent years and are likely to continue to evolve. There is greater emphasis on making appropriate long-term investments for the future and a lower overall life cycle cost. This includes an increased expectation to prioritize sustainability of operations and maintenance. These changes are congruent with a shift toward resource recovery and the expectation for more readily realizable benefits to be derived from WRRF projects.
The focus now is on planning and designing facilities that are less costly to operate and maintain over the facility's full life cycle and more resilient to near-term and long-term change. New facilities are expected to have significantly reduced energy consumption, modern automated equipment with less downtime, cost less to operate and maintain, be more resilient to weather extremes, require less chemical inputs, and be able to offer marketable products through resource recovery. These trends are driving facility managers to better balance utility finances through improved control over operating energy and chemical use, and through creation of new revenue sources.
We are also witnessing an increased public expectation for wastewater utilities to establish defined goals that reduce negative aspects and improve the benefits of wastewater infrastructure for future generations. Accordingly, the public expects greater community engagement in planning public infrastructure projects, more attention to equity and social justice with respect to facility siting and other neighborhood effects, inclusion of public amenities, and overall more transparency and justification in decisions made by local government. Leadership, vision, transparency, long-term view, fairness, and collaboration are skills needed in this arena. Now is the time for utilities managers to relish the opportunity to engage with the public and spotlight the important work done at WRRFs.
When commencing an initial review of sustainability and/or energy management for WRRFs, the first step is to establish the boundaries for the analysis. This includes setting economic parameters, environmental analyses, and/or geographic/community