According to the National Oceanic and Atmospheric Administration (NOAA), the last decade has included some of the warmest years on record in the United States. During this time, large parts of the country experienced prolonged and severe droughts.
In addition to climate-related factors, the lack of infrastructure coupled with population growth in certain regions of the United States is also contributing to increased demand for potable water and exacerbating the effects of droughts.
As more people move to these areas, municipal water supplies are under increasing pressure to meet the needs of growing populations, putting additional stress on already limited water resources, especially during drought conditions. This is particularly problematic given that water scarcity can lead to significant economic, social, and environmental impacts, including reduced agricultural yields, increased wildfires, and diminished water quality.
To address these challenges, many communities are exploring the use of water reuse facilities to repurpose wastewater for non-potable uses. By reducing demand for potable water, these facilities can help alleviate pressure on municipal water supplies during droughts and build greater resilience in the face of changing climate and population dynamics. PCL Construction has experience across the United States building a variety of innovative water reuse and drought resiliency projects.
“PCL creatively applies expertise and technology gained from other markets and industries to water reuse and drought resiliency projects throughout the country,” said Mike McKinney, PCL’s senior vice president civil.
The Colorado River Basin supplies drinking water to 40 million people in the United States; however, due to extremely low water levels this year, states are being asked to cut their Colorado River water use. Arizona, for example must cut its use by more than 20%.
The concern? Phoenix’s existing infrastructure won’t be able to supply northern Phoenix with enough water. The City’s Central Arizona Project (CAP) — a 336-mile canal that diverts water from the Colorado River – only supplied water to northern Phoenix and faced substantial cuts. The Salt River — which experienced a decent rainfall and snowmelt — was only used to feed south Phoenix.
The PCL team was hired to construct a booster pump and pressure reducing valve station to supply water to north and south Phoenix. The pump station mechanically forces water through a pipeline over the Phoenix preserve so water can be pumped interchangeably from the Salt River to north Phoenix and can also feed water from CAP to south Phoenix.
The challenge PCL faced with this project was the expedited timeline. The team had 19 and a half months to complete the project before the water cuts went into effect on Jan. 1, 2023. PCL finished the pump station two weeks ahead of schedule and turned it over to the City for operation.
California has also experienced significant droughts leading to severe water shortages, crop losses and economic impacts.
PCL is currently working on the City of San Luis Obispo’s (SLO) largest-ever public works project, SLO Water Plus. The City of San Luis Obispo’s Water Resource Recovery Facility (WRRF) is more than 90 years old and treats all the wastewater within the city, Cal Poly and the County airport — approximately 4.5 million gallons of wastewater daily. The PCL team is upgrading the facility to recover resources traditionally classified as waste, helping to improve the plant’s efficiency while reducing the dependency on reservoir and groundwater supplies. The project scope includes retrofitting primary clarifiers, creating new aeriation basins, and building fine screens and a new membrane bioreactor facility. Ultraviolet disinfection is being added to further treat the water (which currently goes through a chlorine contact basin). With these advancements, reuse can be expanded and take further demand off potable water supply because it can be used for irrigation.
“Water is one of the only mandatory things we need to survive and is often overlooked,” said Jon Merryman, PCL project manager. “The fact that we get to make a lasting impact on the surrounding communities’ access to water and be good stewards of the environment makes what I do day in and day out worthwhile.”
Water is essential to life, and as drought continues to threaten the United States, so too do harmful pollutants that threaten our water supply. PCL is currently working on a project in Colorado for the South Adams County Water and Sanitation District to remove PFAS (per- and polyfluoroalkyl substances) from groundwater wells. After voluntary sampling by the District in 2018, PFAS was identified in the groundwater supply. PFAS are a group of man-made chemicals widely used in industrial processes and consumer products, such as non-stick cookware, stain-resistant fabrics and firefighting foam. These chemicals do not break down easily in the environment and can accumulate in soil, water and food over time, having harmful effects on human health.
Today, the District must purchase water from a neighboring municipality because it does not have enough capacity in its Granular Activated Carbon system to treat the levels of PFAS in the existing groundwater wells that are contaminated with PFAS. New equipment will be installed at the existing water treatment plant, which will utilize resin to remove PFAS through contact vessels. This will treat the water so it will meet proposed Environmental Protection Agency maximum contaminate levels.
“On this project, we are leveraging the Construction Manager at Risk delivery method to partner with our design and client counterparts to dig deep and find solutions in the preconstruction phase, which is especially important given the volatility in today’s market,” says Daňa Lebeda, PCL area manager. “Bringing the contractor in early to the design process also helps mitigate cost escalation, as the contractor and design team can work through creative solutions before beginning construction.”
Unlike Arizona, California and Colorado, water is not scarce in Florida but the issue municipalities face is the lack of adequate infrastructure to access it. So, the question is, how do we take all the water we do have and make it usable?
PCL is building various water reuse facilities that incorporate AquaDiamond® cloth media filters including one in Manatee County and Pinellas County. Filtration systems like AquaDiamond® are especially important given a recent statewide study that found all but seven of the 113 redfish sampled from Florida’s Gulf Coast to the Atlantic were contaminated with pharmaceuticals.
An AquaDiamond® Cloth Media Filtration System is a type of water filtration system that uses a specialized cloth media to remove impurities and particles from water. It can remove suspended solids, bacteria, and other contaminants from wastewater, producing a high-quality effluent that can be reused for a range of non-potable applications, such as irrigation, industrial processes, and toilet flushing.
From coast-to-coast water is vital in our communities, but the infrastructure needs require unique, creative strategies to deliver effective solutions to our water infrastructure systems.
“Working on infrastructure that isn’t always seen but used by everyone every day is incredible rewarding, said David Griffin, PCL project manager. “I love being a part of helping the environment and the surrounding community.”