Water and Wastewater Treatment Solutions

Gannett Fleming is ready with the latest in water and wastewater treatment methods and technologies for your specific conditions. Whether modernizing aging assets or designing new systems, we can help you:

  • Maintain rates.
  • Minimize operating costs through efficient operation and management.
  • Achieve compliance through appropriate process controls.

Water Treatment

We have decades of experience solving complex water treatment challenges. We are also ranked among the top water treatment design firms by Engineering News-Record (ENR) and understand the challenges you face, including:

  • Aging infrastructure.
  • Program funding.
  • Evolving system needs.
  • A rapidly changing regulatory environment.
  • Residuals management.

Our award-winning work for public and private clients includes planning, designing, and managing construction for water treatment plants with capacities between 0.1 and 300 million gallons per day (MGD). We also modernize, rehabilitate, and expand existing facilities to meet clients’ evolving capacity and treatment needs. As such, we can guide you through conventional treatment processes, such as:

  • Chemical coagulation.
  • Flocculation.
  • Granular media filtration.

We can also guide you through processes like:

  • High-rate clarification.
  • Membrane technology.
  • Advanced oxidation processes.

Specialty Solutions

PFAS and Emerging Contaminants

Water providers and municipalities are grappling with the presence of per- and polyfluoroalkyl substances (PFAS) like perfluorooctanoic acid (PFOA) in their source supplies. Introduced into the environment decades ago by manufacturing and fireproofing processes, PFAS are the subject of increasingly stringent regulations.

Extremely persistent, PFAS can be removed from water through:

  • Adsorption.
  • Using granular or powdered activated carbon.
  • Anion-exchange resins.
  • Filtration techniques.

Our experts can determine the specific removal processes best suited to your individual circumstances. We carefully consider:

  • Space constraints.
  • Backwash requirements.
  • Capital and operating costs.
  • The presence of other elements that could be addressed by co-treatment.

Advanced Oxidation

Advanced oxidation processes (AOP) serve to maximize a treatment system’s oxidation potential, while requiring a short contact time and small footprint. They can fully break down many organic compounds in source water. This includes contaminants that are otherwise difficult to remove.

AOPs harness the disinfecting properties of ozone, hydrogen peroxide, and ultraviolet (UV) light — separately or in combination — to effectively remove persistent organic pollutants from drinking water. Our team can design advanced oxidation solutions that meet your needs and help sustain your communities by first establishing:

  • Treatment goals.
  • Dose.
  • Energy.
  • Operational requirements.
  • System costs.

Membrane Filtration

Membrane filtration uses synthetic organic polymers to remove particulate and microbial contaminants from source water, down to an atomic level. Ultrafiltration, microfiltration, and nanofiltration separate concentrate from filtrate to meet a variety of treatment needs. Reverse osmosis, often used for desalination, is increasingly being used in water treatment applications.

Our experts can determine if membrane filtration is the best solution for you— balancing the costs of pretreatment, maintenance, and backwash disposal with the benefits of a high-performance system that:

  • Fits a small footprint.
  • Provides effective treatment.
  • Reduces chemical use.

Water Treatment Solutions Include:

  • Advanced oxidation.
  • Chemical feed systems.
  • Conventional & high-rate clarification processes.
  • Granular activated carbon treatment.
  • Granular media & membrane filtration processes.
  • High-efficiency mixing, chemical coagulation, & flocculation processes.
  • Ion exchange processes for organic & inorganic removal.
  • Iron & manganese removal.
  • Nanofiltration & reverse osmosis.
  • Onsite hypochlorite generation.
  • Treatability studies & pilot testing.
  • UV disinfection.

Wastewater Treatment

Inadequate wastewater treatment poses a threat to utility assets, public health, and the environment. And, it puts municipalities and businesses at risk of legal liability and substantial fines.

There is no single approach to treatment. Local regulations and the specific wastewater contaminants in each area demand tailored solutions to best maintain public safety, ensure compliance with pollution control requirements, and achieve sustainability goals. Ranked among the nation’s top design firms for wastewater treatment plants (WWTP) by Engineering News-Record (ENR), we help clients solve their treatment challenges through a holistic approach that combines innovation, practical design, green initiatives, and a century of experience.

Backed by a robust portfolio of wastewater process experience and a reputation for forward-thinking design, we’re driven to ensure your treatment investments provide the greatest return for you and your stakeholders. We’ve planned, designed, and managed construction for WWTPs with capacities ranging from .01 to 370 MGD. As well, we help you upgrade, rehabilitate, and expand your existing facilities to meet your capacity and treatment needs.

Specialty Solutions

Nutrient Reduction and Removal

We also provide advanced solutions to meet higher standards and provide maximum protection for communities. These solutions go beyond conventional biological processes that meet secondary treatment requirements.

To remove nitrogen, ammonia, suspended solids, and other unwanted constituents at totals greater than conventional treatment, we employ:

  • Nitrification.
  • Biological denitrification.
  • Filtration.
  • Microscreening.

Gannett Fleming often delivers nutrient reduction far beyond what is required by state and federal regulations. We enable our clients to meet increasingly stringent nutrient-removal goals through our experience in:

  • Biological oxidation.
  • Adsorption using activated carbon.
  • Nutrient removal using the Bardenpho process.
  • Other leading-edge innovations.

Advanced Filtration, Recycling, and Reuse

Many communities are facing a growing demand for potable water and the need to replenish depleted groundwater supplies. Therefore, they are turning to advanced filtration.

Some communities are substituting nonpotable water reuse to reduce the demands on precious potable water supplies. Physical separation methods such as microfiltration, ultrafiltration, and reverse osmosis use man-made membranes. These membranes operate on an atomic level to provide the highest degree of wastewater treatment. Processes such as chemical oxidation, ozonation, ultraviolet disinfection, and advanced oxidation are coupled with advanced filtration to achieve disinfection.

Our experience designing advanced purification processes enables us to deliver leading-edge treatment to help our clients create millions of gallons of nonpotable water for beneficial reuse, or potable water for groundwater replenishment.

Waste to Energy

Most commonly, wastewater treatment plants with anaerobic digesters use small amounts of methane byproduct to help power their boilers and heat their digesters. However, the balance flares off unused. But as utilities and municipalities seek ways to reduce their costs and meet renewable energy requirements, cogeneration can be a viable option.

Clients with ambitious operational or financial efficiency goals look to Gannett Fleming’s cogeneration experts to harness the value of energy in their wastewater. We flip on its head the traditional view of waste as a liability. Instead, we consider such material a potential resource — one that can help you create a sustainable, self-sufficient community and ease the financial burden on ratepayers by:

  • Removing the need to purchase fuel.
  • Reducing air pollutants.
  • Producing energy at a rate below utility grid power.
  • Improving the reliability of power at your plant.

Wastewater Treatment Solutions Include:

  • Advanced water treatment.
  • Alternatives evaluation.
  • Biological nutrient reduction & removal.
  • Biosolids & residual management.
  • Capital expenditure & operating expenditure (CAPEX & OPEX) evaluation.
  • Characterization analysis.
  • Condition assessment.
  • Energy auditing.
  • Instrumentation & controls.
  • Master planning.
  • Mechanistic modeling.
  • Membrane bioreactors.
  • National Pollutant Discharge Elimination System (NPDES) compliance.
  • Odor control.
  • Operations management.
  • Preliminary design.
  • Process evaluation & design.
  • Resiliency & storm hardening.
  • Sustainable buildings.
  • Toxics control.
  • Value engineering.
  • Wastewater treatability analysis.


Are you looking for a reliable, collaborative partner? Do you have a planning, design, or construction challenge? We want to hear from you.

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Are you looking for a reliable, collaborative partner? Do you have a planning, design, or construction challenge? We want to hear from you.

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