30 years of reliable wastewater Treatment at a U.S. military base

This case highlights the successful expansion and rehabilitation of a military wastewater treatment plant, utilizing an activated sludge process and innovative infrastructure to meet strict compliance standards over 30 years with minimal maintenance.

Chris French

Sept. 19, 2025

4 min read

Key Highlights

The wastewater treatment plant has been operational for over 30 years, maintaining compliance and performance with minimal upgrades.
The rotor aeration system has fewer components than traditional diffusers, which enhances reliability and reduces maintenance costs.
The facility was expanded from 500,000 GPD to 1 MGD, incorporating advanced features like ultraviolet (UV) disinfection and tertiary filtration to meet evolving standards.
Complete rehabilitation included new headworks, diversion basins, and flow equalization to handle heavy wet weather infiltration and maintain treatment efficiency.
The plant’s proven durability and effective operation have earned recognition, including the National Guard Bureau's Environmental Award in 1995.

Robust activated sludge and ultraviolet disinfection equipment provides reliable service for a U.S. military base.

Wastewater biological treatment equipment made by Lakeside has completed 30 years of sterling service at one of the largest National Guard bases in the U.S.

In 1994, when the disk aerators in the treatment plant’s circular aeration basin were no longer providing adequate results, the acclaimed National Guard base (established for over a century) called in Marlar Engineering (now part of Halff Engineering) to address its effluent problems.

The Lakeside Equipment rotors have maintained a long service life for the National Guard base.

More than seven times the design flow from infiltration

“In addition to the age of the 500,000 gallons per day facility,” said Mike Marlar, now vice president of Hallf Engineering, “the site also had a major problem with the tremendous amount of infiltration that was getting into their system. During the wet weather season, this was often as much as seven times the design flow, so no wonder they kept failing to meet compliance.”

He said the military base, which includes multiple weapons ranges and top-tier training facilities, wanted to immediately double the capacity of its wastewater treatment plant. The expansion was driven by a sharp increase in the number of incoming recruits.

“After considering all the options, and thoroughly doing our homework, we specified an activated sludge oxidation process from Lakeside Equipment Corporation," he said. "We built two oxidation ditches side-by-side (with covered Magna Rotors) for a total design flow of 1 million gallons per day (MGD). It really says something that three decades on, it is all still working very effectively. It has always met compliance. That’s some record!”

Halff Engineering also undertook a complete rehabilitation of the collection system. This called for introducing a new headworks facility with a diversion box, so that when heavy wet weather flow reached critical levels, it was diverted into a new equalization basin, which was designed to hold 1.5 MGD. When the weather improved, with less severe rainfall, the sewage could then be diverted back up through the head of the plant for treatment.

Two oxidation ditches side by side (with covered Lakeside Magna Rotors) have worked wonders for the National Guard.

Aerated wastewater was set up to flow to two clarifiers that operate in a series operation to settle out the solids, before the effluent is then further polished by a tertiary (Dynasand) filtration process.Coliform and fecal coliform bacteria were then treated by one of this US States’s first ever ultraviolet (UV) light disinfection system. Parshall flumes on both the influent and effluent ensure that wet weather flows can be comprehensively monitored. Sludge was initially dried through a reed bed process and was more recently changed to sand drying.

“When the plant first went online in 1995, it won the National Guard Bureau's Environmental Award," Marlar said. "In 30 years, we've only had one upgrade project, which was a little over 10 years ago in 2015. This was simply to replace some of the UV lights and some minor pieces of equipment. It has all been a very stable process indeed. The National Guard are rightly very pleased with it."

Marlar enginering oversees the maintainance of the plant as well as the operations, which are handled by a licensed operator.

Since installation, the equipment has maintained the strictest compliance for the base.

Equipment longevity matters

The National Guard base has opted for Lakeside Rotors over traditional aeration systems, citing their simplicity and reliability. Unlike systems that rely on dozens of diffusers, the rotor setup requires far fewer components, which translates to less maintenance and fewer replacement parts over time.

“In terms of numbers,” Marlar concluded, “and the likelihood of failures, there are just two Lakeside Rotors, whereas some aeration basins can have anything from 20 to 40 diffusers, which will inevitably mean more maintenance and more replacement parts.”

After more than three decades in the field, he has seen Lakeside’s equipment perform consistently across municipal and military installations. In his view, the system at this base stands out as one of the most reliable he has ever encountered.

"It has a phenomenal record. It all stacks up," Marlar said.