Environmental Dynamics International

Engineered aeration systems and services inside the Nexom family!


means we support engineers from the first design, contractors with the easiest installation processes, and plant operators over the full life of any aeration project.

Whether municipal or industrial, dischargers can offload their specialized care and maintenance to EDI, for long-term performance and system reliability.

In order to rely on your aeration system, you want it designed by experts to meet your specific needs. For nearly half a century, EDI has been making customized aeration solutions accessible to all wastewater treatment plants with:

EDI is proud to be a Nexom brand. Combined EDI with Nexom technologies, capabilities, and experience provides unique customer specific solutions. The EDI-Nexom team will guide you to a reliable treatment solution that is easy to maintain and operate.

What other operators have said:

“While working with SiteWorks crews, we have been able to do improvements to the system to make it run more efficiently. The crews are well-trained on the systems and know what it takes to fix any problem that may come up.”
— Larry, Operator – City of Linn

What other contractors have said:

“We purchased the Extended Warranty with annual inspection to make sure the performance stays top-notch. They have lived up to their guarantee on this spectacular design and installation.”
— Eddie Sechrest, Midwestern Refinery Contractor

What other operators have said:

“The crew you sent here was one of the best I have ever had the pleasure to work with.”

— Maury Dobbs, Seward, IL

What other directors have said:

“The project has been a great success, providing EDI technology is not only reliable, but also simple and easy to install.”
— Bengt Lindqvist, Managing Director Bentrex Oy

What other directors have said:

“Today, we are exceeding our original (effluent improvement) goals, and can reduce total phosphorus… due in large part to the robust system design.”
— Frank DiScullion, Director at City of Lebanon Authority

Advanced Aeration

Optimal System Configuration and Design with Disc, Tube, and Panel Diffusers

Industrial Solutions

Design | Installation | Service

Diffuser Express

Suppliers of Diffusers, Replacement Membranes, and Specialty Diffuser Items Across All Brands


System Evaluation | Installation | Maintenance | Service Contracts

Engineered Aeration

Our fine and coarse bubble aeration technologies are ready to form an integral part of your biological wastewater treatment system

In most modern treatment systems, aeration is the critical component…

that adds air into wastewater that is required for micro-organisms to break down contaminants and pollutants.

It is basically farming bacteria using air to treat wastewater. But it is more than just adding air to a system, to avoid using more energy than required for each situation and to meet or exceed limits, this biological process is optimized by engineering for desired flow, load, capacity, influent type, treatment process type, desired effluent quality, capital investment, operation costs, and energy savings. Add on our long-term maintenance and upgrade support and your wastewater treatment system will be fully cared for by our Aeration for Life promise. EDI has been providing aeration excellence while pioneering and revolutionizing aeration technologies for nearly half a century – since 1975.

How an EDI Engineered Aeration system works:



  • EPDM / PTFE-coated EPDM
  • Standard or High-Temp PU
  • EDI-exclusive Matrix™ / MatrixPlus™
  • Silicone
  • Specialty Polymers


FlexAir® Fine-Bubble

  • FlexAir Disc
  • FlexAir Tube
  • FlexAir Panel
  • FlexAir MiniPanel

CoarsAir™ Coarse-Bubble

  • CoarsAir Hex
  • CoarsAir Max
  • CoarsAir Wide-Band (SS)
  • CoarsAir PermaCap
  • CoarsAir FlexCap
  • CoarsAir AirCone


SiteWorks™ teams provide expert installation & maintenance services

Diffuser Express® is your one-stop online shop for parts for all brands of aeration systems.

Fine Bubble Aeration

Efficiently and reliably transferring oxygen to water.

Maximum Performance and Flexibility to Optimize Your Aeration System.

Fine bubble aeration is a form of subsurface aeration that introduces air into water via very small (or fine) bubbles (<2mm in size).

The fine bubbles produced from the pores promote oxygen transfer which has higher collective surface area of air-water interface compared to coarse bubble systems; diffusing more air into the wastewater as a result.

The low buoyancy of fine bubbles also contribute to the high oxygen transfer. A slow rise to the surface allows more oxygen to transfer from the bubble, and to dissolve into the water at all levels before reaching the surface.

Fine bubble diffuser configurations are designed to be highly efficient; it provides 6–7 lb/O² hp-h, making it 40–60% more energy efficient than coarse bubble or other types of aeration systems.

Use SiteWorks for your complete single-source easy installation and upgrade to fine bubble aeration from any other system type.

We are making a difference in the water reclamation industry.

Take a moment to worry about your aeration one last time before clicking here, and we will take it from there.

Coarse Bubble Aeration

More mixing, less maintenance.

Coarse bubble diffuser systems offer low-maintenance mixing.

Where oxygen transfer isn’t your limiting factor, EDI’s full-range of CoarsAir* coarse bubble diffuser platforms provide mechanical reliability, application flexibility, and ease of installation and maintenance.

The primary advantage of this technology is its robust design and ability to mix heavy consolidation of solids. There are no moving parts in the water and the large bubble orifices can be less prone to clogging; making this a robust solution for difficult aeration/mixing applications

Coarse bubble diffusers get their name from the type of bubble they produce, i.e. greater than 4mmØ bubble diffusers, each attached to a PVC or stainless steel air supply line fixed to the bottom of the treatment basin or tank. When large bubbles are released at the bottom, water is pulled toward the surface along with the large bubbles mixing the wastewater in the basin or tank.

*CoarsAir Includes, MaxAir SS and PVC, HexAir, PermaCap and other EDI coarse-bubble technologies

Soluble Organic BOD removal

Efficient oxygen transfer to help the bacteria already in your plant to remove nutrient pollution and break down solids

Biochemical oxygen demand (BOD₅) is the most widely used parameter applied to the study of wastewater. It is a measure of the dissolved oxygen required by microorganisms, such as algae or bacteria, to oxidize or decompose the organic matter present in wastewater.

Organic substances present in wastewater are typically molecules based on carbon that include fecal matter as well as detergents, soaps, fats, greases and food particles. Inorganic substances are a group of chemicals that contain no carbon and include ammonia, hydrogen sulfide, all metals, and other elements such as calcium and phosphorous.

Oxygen is required for microorganism to break large molecules into smaller molecules and eventually into carbon dioxide and water. The amount of oxygen required for this process, BOD, is the most common measure of the strength of sewage.

The amount of dissolved oxygen in water is an important indicator of the life-supporting ability of a river or stream. Ecosystems are dependent upon adequate dissolved oxygen to remain healthy and productive and wastewater with high concentrations of BOD deplete such Oxygen from these natural resources.


  • Provide oxygen to the beneficial microorganisms in the wastewater treatment plant
  • Keep a healthy population of such microorganisms in your wastewater treatment plant
  • Treat wastewater before it hits the environment

Aerating with EDI’s FlexAir fine-bubble aeration enables the microorganisms to thrive and to oxidize and decompose the organic matter present in the wastewater throughout the entire depth of the basin.

Laboratory and Field Test Services

Few things in life are certain. But knowing your system will work or is working can be one of them.

Active wastewater treatment plants simply can’t be treated like an experiment, or have a technology supplier that just guesses what you need.

With our laboratory services and in-house testing facilities at both our Winnipeg and Columbia locations, as well as field-test unit and evaluation services, our team of engineers and Ph.D’s can help you get the assurance you need that your reaction kinetics are dialed in, your aeration performance metrics are precise, and much more. And you can access these services before, during, and well after you commit to our technologies.

Factory Aeration Testing Facilities for Oxygen Transfer

  • Two Full Scale Tanks
    • 8’ x 25’ floor area x 16’ deep (22,000 gal)
    • 10.7’ x ~18.7’ floor area x 29’ deep (42,000 gal)
  • 75hp Blower for Air Supply


  • Dissolved Oxygen Probes
  • TDS/Conductivity Meter
  • Various other Sensors (flow, temperature, pressure, etc.)
  • Data Acquisition System with Data Logging
  • Underwater Cameras

Offgas Oxygen Transfer Testing

  • 1,000 gal column reactor
  • Three compressors to provide various required airflows
  • Instrumentation
    • DO Probe
    • Offgas measurement panel
    • Data Acquisition System

Materials Lab

  • Tensiometer
  • Two extraction apparatuses (measures extractable oil)
  • Incubator Oven (0 – 290°F / 2.4cu.ft.)
  • Filtration Pump
  • Test Tank (25gal)

R&D Lab

  • Four Tanks (100 – 150 gal)
    • Multiple compressors to provide various required airflows
    • Cycling timers
    • Temperature control capabilities for water and air
  • One 7’, 950 gal Tank with 10 HP Blower
  • Compression Vessel (to simulate tests at greater depths)
  • Fixture for Fatigue Analysis
  • Hydraulic Lifting Rig with Load Cell (2,000 lbs.)
  • Incubator
  • Instrumentation
  • Data Acquisition System
  • Various Sensors (flow, temperature, pressure, etc.)
  • Underwater Cameras
  • Field Instrumentation
    • Colorimeter (NH₃, NO₃, NO₂)
    • 3D velocimeter
    • Sludge Judge
    • Settleometer

We work for you.

No two aeration basins are identical, and we're here to meet the needs of them all.

It starts with you.

We can talk all day about aeration, but unless we are meeting your needs, we haven’t done our job.

Many of our customers fall into the following groups. Don’t find yourself represented? Please reach out so we can help you meet your wastewater aeration goals, too.

Consultants and Engineers

Equipping you with the precise tool for the job, but also the confidence it will get done right.

We’ve designed our processes and hardware with engineers in mind.

From introduction through implementation, we supplement engineers and consultants’ workflow to satisfy your municipal/industrial clients by expediting the entire project, providing superior technologies and offering responsive service throughout.

Let EDI support you with unique process design and high-value engineered solutions, long range of high-quality diffused aeration products that you can trust, best system solutions with highest energy efficiency, performance, lifelong maintenance and upgrade service for your client.

Our simple process outlines what you can expect, although our responsive team is always happy to consult further at any point:

Submit your RFP

...or simply reach out to our friendly staff and have them walk you through the details we need. Yes, you can get started today!


You receive design support and final design-ready drawings, with the support of our expert engineers who work with you to identify the solution to your wastewater treatment requirements.

We Supply Our Exclusive Technologies

Our exclusive technologies will set your project apart and are delivered to site on time to keep contractors on schedule and accountants happy. Our qualified staff commissions our installations, assuring clients that our technologies work to specification and equipping operators with the knowledge they need from day one.

Never Worry About Nutrient Limits Again

We continue to stand behind the installation, long after the shovels and hardhats have left the site. Our support teams ensure our technologies exceed expectations, and they equip operators with the knowledge they need to keep it that way. Throughout the long life of the technology, our friendly staff is ready to supply any needed service or parts. After all, we are committed to our mission, that no engineer or operator should ever have to worry about nutrient limits again.

The heroes of cleaner water.

Cities, Utilities, and Operators of Municipal Treatment Plants

We honor our heroes by giving them our very best.

Since 1975, EDI has been innovating, perfecting, and revolutionizing aeration technologies for cities, utilities, and operators of a vast network of publicly-owned municipal wastewater treatment plants that are working hard to restore and maintain the chemical, physical and biological integrity of the world’s waters. These plants treat municipal wastewater collected from homes, businesses and industries before it is discharged to water bodies or land; and still remain the first line of defense against water pollution as the biggest growing infrastructure to ensure access to cleaner water by the general population on a global space.

We call the cities, utilities, counties, towns, and all the operators of municipal wastewater treatment plants our heroes of cleaner water. To provide them with aeration technologies to ensure long-term compliance and peace of mind is our biggest mission.

With thousands of those plants using our aeration diffusers and systems, we talk to our partners and plant operators daily. Thus, we very well know the pain points. We see many of the wastewater treatment facilities are worn and old now. Those plants require further improvement, repair or replacement to stay in compliance with stringent regulatory requirements and maintain their useful life to serve growing population. Our SiteWorks™ and Diffuser Express™ are there to ensure lifetime source of aeration parts and maintenance/upgrade services for all brands for the lifecycle of Municial Treatment Plants.

We have prepared an easy button for you, with our turnkey integrated solutions with aeration, diffusers, blowers, mixers, controls, and services all put together to meet your budget and treatment goals. We have the range of products, technologies, and design solutions to ensure best resource utilization with your capital investment and operating expenses, so that your lifetime cost of ownership is optimized. Plus, our aeration systems have proven to save up to 50% in energy cost.

What our municipal clients say about us:

Grantsville, UT: IDEAL

IDEAL extended aeration system and batch reactor process doubles treatment capacity for lagoons just south of Great Salt Lake.

read more

Industrial-Strength Aeration

for Industrial-Strength Needs

Our installations and technology treat wastewater from many industries.

We have experience in most types of industrial wastewater

To learn more about what we have done for various industries and what we can provide for your project, choose an industry below.

Have a treatment need that will require a custom fit and advance testing?

Consider our testing programs. Contact Engineering today.

Environmental Dynamics International

About Us

About Our Company

In June 2020, EDI integrated into Nexom after having been acquired by KKR and XPV Water Partners. This integration empowers EDI for a much stronger position in the global market with enhanced, synergistic capabilities and a wider range of solutions in our integrated portfolio of biological treatment and filtration technologies.

Environmental Dynamics International (EDI) was founded in 1975, with a focus on Biological Treatment and Advanced Technology Diffused Aeration Systems. The company continues to grow with its diverse product portfolio and unparalleled service capabilities; offering integrated aeration system solutions for Municipal and Industrial Water Reclamation Facilities. The corporate campus in Columbia, Missouri, USA is the R&D, engineering and design management, and manufacturing center for the organization; featuring world-class test facilities for oxygen transfer, material performance, and product design.

EDI continues to support new plant construction, existing facility upgrades, and long-term infrastructure demands on a global scale. To support our global customer base, we have created a network of direct sales representatives and local independent partners. In addition to sales support from the corporate offices, EDI maintains international offices in United Kingdom, Germany, Romania, Mexico, Japan, India, Singapore, and UAE. EDI diffused aeration products have been installed in over 8,000 aeration systems in over 100 countries serving over 400 million people.

EDI has been revolutionizing wastewater aeration technologies since 1975. We are focused on helping our municipal and industrial clients manage their environmental impact with the lowest possible lifecycle cost.

EDI is recognized for excellence in exports and has received numerous awards including: State of Missouri “Small Business Exporter of the Year” Award and US Dept. of Commerce President’s “E” Award for Excellence.


People Served Worldwide

Countries with Running Systems

Proud Water Environment Federation (WEF) member