Insight into our dynamic project portfolio

Principal Investigator: Treavor Boyer

Ion exchange (IX) treatment is considered one of the most effective technologies for PFAS removal from water. Despite its effectiveness, there is a need to define when regenerable IX treatment makes sense for drinking water applications in Arizona and to identify the best practices in site-specific assessment of regenerable IX treatment. The approach for this project is to evaluate the regeneration efficiency of IX treatment for PFAS, and to identify key components for implementing and costing a regenerable IX treatment system. The expected benefits of this project include new performance data, new cost estimates, and improved understanding of regenerable IX treatment for PFAS-impacted water resources in Arizona, which will support ADEQ in reviewing and permitting regenerable IX treatment systems and support public water systems in designing and operating the systems.

Principal Investigator: Anca Delgado
Co-Investigator: Otak Conroy-Ben

Nearly 120 miles of surface water in Arizona are contaminated with mining waste containing heavy metals and acid discharge. Traditional technologies such as limestone channels increase alkalinity and are effective at removing certain metals but add hardness to an already impaired water. We are evaluating passive and active remediation technologies for stream restoration under harsh environmental conditions. Combinations of limestone, lime, soda ash, and biochar are assessed for metal removal, recovery, and water quality.  Sulfate-reducing bioreactors are designed for metal-sulfide precipitation and metal recovery, either as the main heavy metal treatment or as a final polishing reactor.  These technologies will help reach the goals of protecting Arizona’s surface waters through metal remediation and co-recovery.

Principal Investigator: Peter Fox

Arizona faces an urgent need for sustainable brine management strategies as desalination and industrial water use grow, straining limited disposal options and challenging state regulators. Our project directly addresses this by conducting a comprehensive assessment of innovative technologies, from high-recovery desalination and mineral extraction to the feasibility of deep well injection, creating integrated solutions tailored for Arizona’s unique brine chemistries. Preliminary economic analysis demonstrates the clear benefit of deep well injection (DWI) as compared to evaporation ponds. The primary benefit of this research is providing the Arizona Department of Environmental Quality (ADEQ) with a data-driven framework to develop effective regulations, enhancing water security through greater water recovery, and creating new economic opportunities by turning brine into a valuable resource.

Principal Investigator: Tianfang Xu

Arizona’s reliance on groundwater demands proactive quality management, yet comprehensive monitoring of contaminants across over 100,000 domestic wells and small drinking water systems is prohibitively expensive and logistically challenging. To overcome this barrier, our project leverages transfer learning, integrating sparse local data with national/global datasets to train machine learning models that predict contaminant concentrations spatially and temporally using physiographic, climatic, hydrologic, and anthropogenic drivers. By enabling cost-effective identification of at-risk aquifers, forecasting noncompliance risks, and optimizing sampling strategies, this project aims to empower ADEQ to allocate resources efficiently while safeguarding water quality.

Principal Investigator: Ruijie Zeng

Contaminant effluents from Onsite wastewater treatment facilities (OWTFs), such as cesspools and septic tanks, cause environmental concerns and health risks, especially is rural areas. Missing information on the number and location of OWTF limits state agency Arizona Department of Environmental Quality (ADEQ)’s capacity to mitigate the impacts of OWTF. This study, funded by GCWT, collocates with ADEQ and local communities to develop spatial analytics to identify OWTF inventory in Arizona rural communities and assess the environmental risks associated with OWTF effluents. Outcomes from this project will help state agency better allocate resources for OWTF replacement and upgrade and improve environmental and public health in vulnerable communities.

Principal Investigator: Paul Westerhoff
Co-Investigators: Mariana Bertoni & Tiezheng Tong

Arizona is now a global semiconductor manufacturing hub despite extensive drought conditions, and faces significant sustainability challenges due to the industry’s high demand for ultrapure water and complex wastewater management. As the design of modern semiconductor chips reaches sizes of below 10 nm, the impact of minute contamination becomes increasingly vital for the final quality of the devices. By working with our industry partners, we will identify what intrinsic defects of the semiconductor material and extrinsic defects of the ultrapure water system used throughout the manufacturing process have the potential to impact the quality of the semiconductor material. Through the use of state-of-the-art techniques that address the location, composition, chemical state, band structure, and nearest neighbor environment of defects, we will quantify the impact of these chemical impurities on material properties.

Principal Investigator: Matt Green

This project develops zwitterion-modified polysulfone membranes for energy-efficient desalination to address Arizona’s water future by treating saline feedstocks with reduced energy and maintenance costs. The approach involves synthesizing and characterizing membranes with high zwitterion content to enhance water permeance and salt rejection, using pervaporation to minimize energy demands, and incorporating chemical crosslinking to improve mechanical stability. To optimize energy efficiency and recyclability, we incorporate mechanistic studies on biofouling and scaling, alongside process modeling. The benefits of this are sustainable access to potable water, reduced water waste and reduced desalination energy costs.

Principal Investigator: Nariman Mahabadi
Co-Investigators: Edward Kavazanjian

In Arizona’s rapidly growing industrial sector, a single semiconductor plant can lose up to 5 million gallons of water per day through evaporative cooling —an unsustainable strain on the region’s already limited water supply. With extreme heat and prolonged drought intensifying across the state, there is an urgent need for water-efficient cooling solutions that work in arid, high-temperature environments like Maricopa County. This project develops Engineered Geo-Cooling systems specifically designed for Arizona’s climate. These systems collect heat from industrial buildings and transfer it into the ground through closed-loop pipes, using high-conductivity geomaterials to enhance thermal exchange, eliminating the need for evaporative water loss. The team combines advanced simulation, lab-scale testing, and material innovation to engineer efficient, site-adapted ground-coupled heat pump (GCHP) systems. Engineered Geo-Cooling has the potential to dramatically reduce water use and cut energy consumption by up to 72%, providing a scalable, low-maintenance, and long-lasting cooling solution for Arizona’s industrial infrastructure. This technology directly supports the state’s water resilience and climate adaptation goals. Unlike conventional cooling towers—which are incompatible with Arizona’s water challenges—Engineered Geo-Cooling offers a transformative, dry-climate-ready alternative that could become the new standard for sustainable industrial cooling across the Southwest.

Principal Investigator: Tiezheng Tong

Silica scaling is the main constraint that limits the water recovery of desalination and brine treatment. This project aims to develop novel mitigation strategies to control silica scaling in low-salt-rejection reverse osmosis (LSRRO) as an emerging technology towards minimal liquid discharge (MLD), reducing the cost and energy consumption of membrane-based desalination and wastewater treatment towards a circular water economy. It will benefit multiple industrial sectors where membrane desalination and hypersaline brine treatment are needed.

Principal Investigator: Xiangfan Chen
Co-Investigator: Chao Ma

Access to handwashing facilities is vital for preventing the spread of infectious diseases, safeguarding public health, and maintaining hygiene in both routine and emergency contexts. However, handwashing generates significant amounts of greywater that is challenging to fully reclaim for reuse. Our solution focuses on developing an energy-efficient greywater treatment technology tailored for handwashing applications. This approach reduces treatment costs, promotes broader use of recycled greywater, and mitigates health risks.

Principal Investigator: Dwarak Ravikumar
Co-Investigator: Saurav Kumar

The increased deployment of water-based evaporative cooling towers to meet cooling needs of industrial and commercial facilities can exacerbate the water stress in Arizona. Despite these concerns, there exists no robust method to estimate the water footprint and losses from cooling towers currently installed in Arizona. Our research combines artificial intelligence, computer vision and physics-based models to determine the geospatial spread of cooling towers in Arizona and estimate their water footprint and losses. The findings from our research will help water planners and the city and state government to plan and minimize the water requirements to meet the future commercial cooling needs through a mix of air-based conventional cooling technologies and cooling towers

Principal Investigator: Bruce Rittman
Co-Investigator:YenJung Sean Lai

Given more stringent PFAS regulations, many drinking-water utilities soon must implement PFAS treatment, but currently available technologies only remove PFAS from water into an adsorbent medium (e.g., granular activated carbon (GAC)) or concentrate the contaminants into a brine stream (e.g., reverse-osmosis (RO)). The spent media or the concentrated brine require additional and expensive treatment prior to safe disposal. Treatment technologies that can fully mineralize PFAS into carbon dioxide and fluoride ion are a pressing need. The membrane catalytic film reactor (MCfR; as shown in Figure 1) has demonstrated outstanding defluorination performance for the range of PFAS. This gives the MCfR a large advantage over conventional techniques because it destroys PFAS, not just removes it. Also, the MCfR can be implemented at ambient temperature without extreme inputs of energy.

Principal Investigator: Seth Tongay

There is an ever-growing demand for accessible water across all sectors, particularly for high-quality water that meets drinking and manufacturing requirements. In order to ensure these needs are met going forward, it will be necessary to establish new sources of water generation. One promising solution that has garnered significant interest is that of using metal-organic framework (MOF) materials for capturing ambient water from the air, a concept commonly known as atmospheric water harvesting (AWH). However, while great progress has been made in the development of water harvesting MOFs, their widespread adoption into the AWH space has been slowed due to the complexities and costs associated with bringing production to scale while maintaining the desirable efficacy.

The goal of this project is to overcome these challenges through the design of a manufacturing process that allows for the affordable production of various MOFs with consistent quality to support production levels ranging from academic to industrial requirements. Additionally, this project aims to further maximize the impact of these MOFs by implementing green synthesis methods. By concentrating on providing a production process that is cost-effective and quality-preserving, those seeking to use MOFs for AWH and other resource stewardship applications can focus on their implementation goals.