Research and Development Office

Goodyear Pilot Wetlands: Developing Hydraulic Loading Rates, Hazardous Waste Disposal Requirements, and Optimum Operations for an Inland Concentrate Management Alternative

Project ID: 2922
Principal Investigator: Deborah Tosline
Research Topic: Water Quality
Funded Fiscal Years: 2016, 2017 and 2018
Keywords: None

Research Question

Water supplies are limited in the western U.S. and water resource managers strive to beneficially utilize all
available water sources. Desalination of brackish groundwater provides an additional drinking water supply;
however, in inland areas environmentally sound disposal of concentrate is a major challenge. Current concentrate
management alternatives require either high capital and power costs, or large land areas.
Previous S&T funded research (S&T 3699) and continued work by the City of Goodyear (Goodyear) and PXAO has
shown, at the pilot scale, that engineered vertical flow treatment wetlands (VFTW) successfully reduced arsenic,
selenium, chromium and nitrate concentrations to below regulatory standards for surface water discharge.
Therefore, VFTWs are believed to be a low cost, environmentally sustainable, concentrate management
technology.
Goodyear currently produces about 3.5 million gallons per day (MGD) of drinking water from brackish water
desalination at the Bullard Water Campus Reverse Osmosis (RO) facility which generates about 0.5 MGD of
concentrate (concentrate volume expected to be 28 MGD by 2035). The concentrate is currently discharged to the
sewer system for treatment at the 157th Avenue Water Reclamation Facility. Concentrate disposal via sewer
discharge is not sustainable in the long-term.
This project will leverage past pilot testing experience, equipment, and partnerships to evaluate the full scale
viability of VFTWs for concentrate management and answer the following questions:
How can vertical flow wetlands be implemented in a full scale application to provide a viable inland RO concentrate
management alternative?
What are the design criteria associated with wetlands for concentrate management: i.e., factors contributing to
O&M costs, capital costs?
How can wetlands be incorporated into city education and recreation plans to provide added benefit beyond
concentrate management?

Need and Benefit

Wetland treatment of desalination concentrate has the potential to provide a cost effective, environmentally
sustainable method that beneficially reuses wastewater. The experience and knowledge gained from this project
will provide a model for other inland communities as desalination of brackish groundwater increases. The wetland
treatment concept would increase reuse options of three water types: treated effluent, treated Superfund water,
and pumped Long Term Storage Credits for blending to reduce TDS concentrations for ultimate discharge to the
Gila River.
This proposal focuses on utilizing the cooperative relationship between the City of Goodyear and Reclamation.
The success of the initial pilot led to a partnership between Reclamation and Goodyear on the Goodyear
Demonstration Wetland study to assess the feasibility of scaling up the pilot to a demonstration and ultimately a
full size treatment facility. In 2013, Reclamation provided a $300,000 grant to Goodyear for the study. Goodyear
is developing the engineering design for infrastructure, potential wetland locations, and identifying NEPA and
construction permit requirements. Goodyear now manages the pilot wetland including operation, monitoring and
water, soil, and vegetation sampling for laboratory analysis in preparation for operating the demonstration size
facility. Goodyear supports continued research efforts at the pilot. The Phoenix Area Office continues to support
research at the pilot and is providing funds for Denver TSC technical expertise and support.
Goodyear is partnering with the Maricopa County Parks & Recreation Department to potentially locate the
demonstration and full-scale wetland treatment facilities at the Estrella Mountain Regional Park. This collaboration
would provide land for treatment wetlands, aesthetic landscape features at the park and associated golf course
using salt tolerant native vegetation and provide public amenities, recreation and education opportunities.
Blended water would be discharged to the Gila River within the El Rio Watercourse Master Plan, developed by the
Flood Control District of Maricopa County. The El Rio Watercourse Master Plan would improve flood control within
a 17.5 mile reach of the Gila River and develop a recreational corridor to spur economic development in the West
Valley. Discharge of treated/blended concentrate is currently the only potentially available water source for the
proposed El Rio Watercourse.
The City of Goodyear seeks to develop a cost effective, environmental, advanced treatment alternative that
increases reuse of several "waste" water sources, provides public amenities and educational opportunities and
supports river and habitat restoration. The results from this project will provide a framework for other inland
communities as water managers optimize their water supply portfolios and the need for cost-effective and
sustainable concentrate management options increase. The multiple benefits of this method provide tremendous
potential for widespread adoption.
The Goodyear Wetlands Pilot provides a controlled wetland research facility with the potential to provide results
that are broadly applicable to ongoing concentration management studies and Reclamation S&T research including
the Oxnard Saline Demonstration Wetland, the City of Waco Brazos River Demonstration Wetland, and the data
compilation efforts of the Concentrate Management Toolbox and Selected Case Studies.
Continuing research at the Goodyear Wetlands Pilot supports the potential to share information, augment existing
research, collaborate on future research projects, and benefit from the expertise of Reclamation staff research
efforts. This potential to share and build on existing research projects promotes a cost-effective and efficient
opportunity to optimize research under the S&T program and to maximize the return on program funding.

Contributing Partners

Contact the Principal Investigator for information about partners.

Research Products

Bureau of Reclamation Review

The following documents were reviewed by experts in fields relating to this project's study and findings. The results were determined to be achieved using valid means.

Goodyear Pilot WetlandsDeveloping Hydraulic Loading Rates, Hazardous Waste Disposal Requirements, and Optimum Operations for an Inland Concentrate Management Alternative (final, PDF, 17.2MB)
By Deborah Tosline, Katie Guerra, Catherine Hoffman, Chris Waechter
Report completed on September 30, 2018

Goodyear Pilot Wetlands (final, PDF, 87KB)
By Deborah Tosline
R&D Bulletin completed on September 30, 2019

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