Grey Water Rising


Water efficiency at commercial properties often takes a back seat to larger-budget sustainability goals like energy conservation and indoor air quality. That is changing, however, as the cost of water and wastewater services increases across the United States in response to water scarcity and the need for capital investment in aging water infrastructure.

As more and more building owners and property managers experiment with grey water reuse and recycling, they are discovering that these structural and operational management solutions not only help control overhead, but also enhance resiliency while meeting tenants’ needs.


Grey water describes gently used effluent from showers, sinks and washing machines, as well as rainwater runoff and condensate from building mechanical equipment. It is distinct from both potable water, which is safe for drinking, and wastewater, which can contain harmful biological material. Grey water can contain traces of dirt, grease or cleaning products, but is safe for soil irrigation and toilet flushing.

Grey water systems have inspired some confusion over the years, particularly over the potential exposure to harmful pathogens. But, wary owners and managers have no need to fear. As of 2006, when the United States had more than eight million grey water systems in use subject to 60 years of research by the Centers for Disease Control and Prevention, there was not a single report of grey water-transmitted illness.

Alternative technologies are an imperative where water is limited or population growth is outstripping resources, as it is in the southwestern United States. Yet, grey water and storm water recapture systems offer environmental and economic benefits in any location; in fact, more than 30 states across the United States now regulate water recapturing, with nearly 10 million systems in use nationwide.


Harvesting storm water and grey water offers unique opportunities to recycle water and reduce the impact on both the environment and local infrastructure, with a wide range of benefits. What follows are a few points property owners should consider when planning their own program:

  • Ensure health and safety. Managers should work with contractors to determine what level of on-site grey water treatment, if any, is necessary to meet local regulations for the planned use. Articulate those safeguards to tenants to ease fears and rally support for the initiative.

  • Manage operating expenses. Potable water consumption will decline markedly with a grey water system, particularly at properties where grey water can be applied to landscaping. In those cases, fertilizer application requirements typically decline as well. Properties using grey water in cooling towers also may reduce energy consumption in addition to water bills.

    While grey water systems require upfront capital, these systems can be modified to deliver savings in almost any geography. Climate, building type and occupancy levels play large roles in determining which grey water uses provide the best returns, so work with local experts to attain quicker paybacks.

  • Improve the tenant experience. Grey water measures lack the out-of-box shine that other sustainability investments might offer. It is essential to anticipate concerns and assuage them by preemptively educating end-users on program benefits. Emphasize cost savings and environmental benefits while addressing health and safety questions, and remind them that grey water is never allowed to recirculate as potable water

  • Boost marketing and branding. A significant investment in grey water reuse can demonstrate a solid commitment to the environment and the surrounding community. Grey water systems also support efficiency and are valued highly within green building certification programs.

  • Enhance maintenance and asset management. Owners dipping their toes into grey water for the first time should choose a simple system. Complexity will increase the required investment of staff time and training to maintain the system. By staying ahead of the curve on water conservation and understanding local stressors like water scarcity, property managers can limit risk and liability in a rapidly advancing regulatory environment.

ABOUT THE AUTHOR: As director of Sustainability, Josh Richards leads Transwestern’s energy and sustainability efforts, supporting national operations for all clients. He is spearheading projects that focus on energy and water efficiency and enhancing asset valuation through cost-effective and environmentally conscious investment. He can be reached at

This article was originally published in the March/April 2018 issue of BOMA Magazine.

Building teams looking to reduce water consumption might also consider joining BOMA International’s W2 Challenge, a two-year initiative encouraging property professionals to benchmark water consumption, waste output and costs, then implement best practices to improve performance. Learn more at