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Integrated Approach to Water Reuse

In January 2023, the Department of Interior imposed a Tier 2 water curtailment measure to mitigate the effects of ongoing drought in the Southwest. The declaration was announced in August 2022 based on operating criteria known as the Interim Operating Agreement and the Drought Contingency Plan. Under these arrangements between the seven basin states (Arizona, California, Colorado, New Mexico, Nevada, Utah and Wyoming), less Colorado River water will be used in the greater Colorado River Basin.


For the seven basin states, significant water reductions present enormous challenges. Arizona faces the steepest reduction of 21%, followed by Nevada at 8% and the country of Mexico by 7%.


In addition to these mandatory cuts, Arizona, Nevada and California reached an agreement in May 2023 to “conserve at least 3 million acre-feet of system water through the end of 2026,” according to the Department of the Interior.


Arizona and water

In 1980, Governor Bruce Babbitt passed the historic Groundwater Management Act (GMA), which created the Arizona Department of Water Resources (ADWR). Prior to 1980, water use in the state steadily rose, but after GMA passage, water use has fallen, even as the population and economy of the state have grown massively.


Arizona is a pioneer of water management, and the state continues to advance conservation to create a durable portfolio of water assets. As an example, “Arizona has stored over three trillion gallons of water for future use. That is equivalent to serving the City of Phoenix for 30 years,” according to Arizona Water Facts. Arizona’s commitment to water sustainability is due to long-term strategic planning in areas of conservation, resource utilization, infrastructure and water stewardship.


In addition to conservation, Arizona has a governance structure for new subdivisions in place. Accordingly, developers or the utility that will serve a new subdivision must prove to the state that a 100-year assured water supply exists before proceeding with a new development. The below diagram shows some of the rigorous requirements of obtaining the 100-year assured water supply.

Total Water Management

Global Water Resources, Inc. (GWR) is a water resource management company that owns, operates and manages 29 systems that provide water, wastewater and recycled water services to utilities in strategically located communities including growth areas surrounding the metropolitan areas of Phoenix and Tucson, Arizona. As one of the state’s largest companies in this sphere, GWR manages more than 300 square miles of certificated service territory. This geographic scale is on par with some of the largest utilities in the country.




The company seeks to deploy their integrated approach, which they refer to as “Total Water Management (TWM),” a term meaning managing the entire water cycle within the same geographic areas in order to both conserve water and maximize its total economic and social value.


GWR uses TWM to promote sustainable communities in areas where the expected growth will outpace the existing potable water supply. This model focuses on the broad issues of water supply and scarcity and applies principles of water conservation through water reclamation and reuse. The basic premise is that the world’s water supply is limited, yet it can be stretched significantly through effective planning, the use of recycled water and by providing individuals and communities resources that promote wise water usage practices.


Total Water Management framework

Water stewardship can best be viewed from a TWM perspective. TWM is a comprehensive approach to water utility management that reduces demand on scarce non-renewable water sources and costly renewable water supplies, in a manner that ensures sustainability and greatly benefits communities both environmentally and economically. This approach employs a series of principles and practices that result in real reductions to per capita demand, while allowing for economic development and other quality of life goals.


The tenet of TWM is, where possible, integrate water, wastewater and recycled water service in the same geographic area as to maximize the use of recycled water and minimize the use of potable water. That means, for each community and unique situation, determining the best use of recycled water targeting 100% reuse and paths to 100% reuse by this list of factors:

  • Direct beneficial reuse of recycled water for non-potable demands within a community requiring a second distribution system

  • Indirect potable reuse, utilizing managed, direct injection and/or soil aquifer treatment recharge and recovery

  • Direct potable reuse, requiring advanced treatment technology and social buy-in

  • Create regional plans to consolidate and integrate water, wastewater and recycled water utilities and resources to the extent possible, and construct regional infrastructure that optimizes use of resources while ensuring the efficient operations of the utilities.

  • Leverage advanced technology that allows for the accurate and meaningful tracking of resources, both water and physical plant, maintaining the performance and health of the related utility assets.

  • Institute programs that utilize data and incentivize behaviors that result in reduced demand of all water resource types, including: the smart application of water rates to encourage efficiency and equitable use; innovative new technologies for water metering and data presentation back to customers in actionable format.

The most important part of TWM is the people aspect: employees, customers, regulators, and regional stakeholders all playing a role. Outreach and educational initiatives are critical to ensure all stakeholders, including customers, development partners, regulators, and utility staff, are knowledgeable of the principles and practices outlined above. Important in this architecture is establishing partnerships with communities, developers and industry stakeholders to gain support for the principals and practices outlined here as TWM, and to develop further legislation, rules, codes, and standards in pursuit of continuous improvement.


Total Water Management is a repeatable model for utilities across the nation, and the globe for that matter.


Final thoughts

By using recycled water for outdoor uses, freshwater use can drop by 40%. To put this into perspective:


The Employment and Population Statistics Department of the State of Arizona predicts that the Phoenix metropolitan area will have a population of 5.8 million people by 2030 and 6.5 million by 2040, an increase of 3.7 million people compared to 2.8 million people reported in the 2010 Census. Each person uses an average of 135 gallons of water per day.

  • 6.5 million people multiplied by 135 gallons = 877.5 million gallons per day.

  • 877.5 million gallons a day multiplied by 365 days = over 320.2 billion gallons per year.

Recycling is the only water source that grows as population does. More people means providers will need an additional 182.3 billion gallons of water per year by 2040 than they did in 2010; but it also means more showers, more baths, and more laundry — so that produces more wastewater. Applying the 40% number means that 72.9 billion gallons per year can come from reuse.

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