Taking the Leap to Advanced Water Treatment

Water resources in the Western United States are becoming increasingly strained because of availability, quality and population growth. Municipalities relying on Colorado River water or groundwater are quickly adopting advanced water treatment (AWT) technologies to ensure a sustainable and resilient water supply. However, adding AWT facilities into the utility water portfolio comes with complex and unique considerations that call for careful planning and collaboration. Through experience building AWT and water treatment facilities designed to take on different or multiple new water sources in the region, here are three key considerations to planning, designing and building AWT facilities, with the end in mind.

Public Engagement and Education Initiatives

Gaining public support is critical. Past experience has proven that engaging with the community goes beyond check-the-box public forums or dense technical presentations. The public needs to be thoughtfully engaged to broaden their lens of water resources and provided opportunities to understand and own both the “why” and the outcomes. 

The process and purpose need to be communicated early on and often, with an emphasis on the need, water quality guarantees and social equity. Utimately, end users really just want to be assured that the water they will have access to is clean and safe drinking water, but less explicity stated, proof that the water is going to taste, look and smell the same (or better). While water professionals know this is happening with technology, demonstrating this to the public is critical.

Municipalities and organizations are getting creative with demonstrating the impacts of AWT on communities. Beyond the well-known tactic of having local breweries make beer using purified water, the City of Scottsdale has advanced public outreach and feedback by making popsicles with flavors representing the community’s thoughts on AWT. 

At last year’s Arizona WaterReuse Conference, McCarthy Building Companies established a partnership with a local coffee house to brew coffee using purified water from the Orange County Water District Groundwater Replenishment System (OCWD GWRS) in Fountain Valley, Calif., an international model for AWT. The feedback received was that the coffee brewed with purified water tasted better than that brewed using current tap water. Past experience hosting taste tests with bottled water and purified water has shown that purified water is nearly always favored. Efforts like this demonstrate the impacts of AWT in ways that community members understand and help them value water resources. 

Public engagement starts early but continues through the life of the facility.In the case of the OCWD GWRS, a pilot system was operated for many years at the groundbreaking Water Factory 21 (the first advanced treatment facility to utilize reverse osmosis) and a robust education and outreach program was implemented to build the public’s trust. These efforts ultimately earned overwhelming community support for the project. Today, OCWD GWRS continues to use the pilot infrastructure to host educational programs to increase comfort and maintain the community’s trust. 

Identify the Best Technologies and Necessary Infrastructure Upgrades

Choosing the right combination of AWT involves several unique non-economic and economic considerations. Beyond the technological feasibility of various treatment options based on the specific contaminants identified in water source assessments, considerations need to be made for brine management, the technical and social implications of distribution system connection locations, and source water blending and system stability. 

At the Chandler Reclaimed Water Interconnect Facility in Chandler, Ariz., McCarthy Building Companies installed Veolia ZeeWeed ultrafiltration membranes, a membrane filtration technology used in advanced water purification processes, to treat multiple sources of surface water from Colorado River and Salt River Project sources with the goal of meeting increased water demands and supporting drought prevention.

On top of non-economic considerations, the selection of technologies and project scope can swing project budgets. Whether it’s an AWT facility or your average wastewater reclamation system upgrade, subcontractor and labor availability, potential supply-chain disruptions, escalation impacts, and new federal funding requirements have made pinning down a reasonable budget a challenge. Utilizing collaborative delivery methods to incorporate industry expertise from the engineering and construction communities to get timely and accurate estimates provides certainty in the AWT technology treatment and project alternatives analysis without the risk of wholesale redesign. 

Planning with the End in Mind

Considerations that are dwarfed in comparison to securing a reliable source of water are often overlooked, but can make or break the success of an AWT project. Municipalities should be planning for an unexpected upstream event like a slug from a major industrial user and determining how that will be handled. They may also consider how influent water quality expectations at the AWT might impact long-term economic development. Downstream considerations include understanding the impacts to the watershed or non-potable customers that rely on wastewater effluent. Taking a deep dive into upstream and downstream impacts early on is critical in order to thoroughly evaluate key project plans as well as to maintain the project schedule and budget. 

While not an advanced water project, the Signal Butte Water Treatment Plant in Mesa, Ariz., further evaluated the impacts of Colorado River source water availability. This deep dive into source water options gave the City confidence in the reliability of this facility and expansion despite the anticipated changes in water availability. The plant is currently undergoing a $56 million phase I facility expansion, which includes building an 8 million gallon potable water reservoir as well as adding redundancies to ensure system reliability and provisions for future expansion.

Transitioning to AWT is a multifaceted challenge that requires careful planning and consideration, which can help provide solutions for many Arizona communities facing water challenges. A customized strategy with a comprehensive plan is the best way to ensure a smooth transition and to achieve the ultimate goal of providing a safe, reliable and sustainable water supply for Arizona communities today and into the future. 

Patrick Payne, Vice President of Operations for McCarthy Building Companies’ national water group, can be reached at ppayne [at] mccarthy.com (ppayne[at]mccarthy[dot]com).