Intermittently-Decanted Extended Aeration Lagoons

It may be an acronym, but if your lagoon removed ammonia, BOD, and Total Nitrogen like this, you'd call it "IDEAL," too.


Your challenge:

Your lagoons have too much loading for their size and/or regulatory limits.

There’s a good chance your lagoons designed for yester-year’s permits, population, or industrial loading. But those conditions change, and they rarely make things easier on your existing wastewater treatment infrastructure. That does not mean, however, you necessarily need to lose or replace it.

Our technology:

High levels of BOD, TSS and ammonia removal with your eye on the future.

Nexom is the exclusive source for IDEAL (Intermittently Decanted Extended Aeration Lagoons). IDEAL systems consist of an optAER® aeration system with fine bubble diffusers, two chains of BioReef BioCurtain, a static decanter with flow control valves, an overflow pipe with Storm Mode, process controls, and a blower package. The simple operation of the IDEAL provides easy, cost-effective operation while the sophistication of the design provides high levels of BOD, TSS and ammonia removal.

The IDEAL process requires no active sludge management and extremely high flow events present no operational problem or concern from washout of the reactor. IDEAL also provides up to 66% total nitrogen removal as part of basic operations, which means you are already prepared for future increases in nitrate or nitrogen requirements. The unique ability of the IDEAL to provide front-of-plant treatment provides several benefits over other lagoon-based technologies.


Key advantages:
  • Proven cold temperature nitrification as low as 3°C
  • De-nitrification over 60%
  • Phosphorus removal and filtration options available
  • Worry-free operation during and after peak-plus flow events
  • Maximum hydraulic capacity

Provides nitrification even in winter conditions.

Incorporates a single lagoon/earthen basin to treat a continuous inflow while maintaining biomass equilibrium.

Delivers high effluent quality for small-to-medium water reclamation facilities while retaining lagoon based operational simplicity.

How it works


IDEAL combines several technological advancements

…not to mention decades of experience.

IDEAL is an advanced upgrade for lagoon-based treatment processes for ammonia and nitrogen removal. It is small-footprint, intensified lagoon treatment which is continuously filled, with an intermittent decant that eliminates pre-equalization. IDEAL incorporates the four specific proven technologies, listed here, and developed across 40 years of Nexom wastewater treatment experience.

optAER® fine-bubble aeration

We could devote a whole page to aerating lagoons with fine-bubbles, so we did.


Our patented BioReef™ BioCurtain incorporates multiple chains of BioReef that act as a biologically activated hydraulic curtain. The BioCurtain incorporates fixed-film technology to increase biomass in the reactor and provide contact stabilization during the settling and decant phases; it acts as a hydraulic buffer to address short-circuiting potential within the reactor and provides additional nitrification capability below 8 degrees Celsius.

Decant Device

Our engineered decanters control effluent flow from the IDEAL BioReactor. The decanter reduces moving parts and reduces operator involvement. The IDEAL decanter is engineered to minimize head loss between the IDEAL and partial mix lagoon, a crucial feature when upgrading an existing lagoon system.

Process Controls

Our unique process controls provide maximum energy efficiency and total nitrogen removal and enable you to meet other data acquisition and reporting needs.

What it Delivers


Front-of-plant ammonia removal

Removing ammonia at the front of the plant provides several benefits. Other processes look to the back of the plant for ammonia removal where BOD concentration is lowest. The IDEAL process removes BOD and ammonia up front where warm, carbon-rich influent water is available to increase biological activity and denitrify for easy recovery of oxygen and alkalinity.

Nitrate and Total Nitrogen Removal

Total nitrogen and nitrate restrictions are on the horizon. Converting ammonia to nitrate is only the first step. Denitrification, or removing nitrate, is the second step necessary for total nitrogen removal. The IDEAL process provides this benefit as a natural function of the process, whereas many other systems require expensive upgrades to achieve similar results.

Long Term Compliance Planning

Upgrades for advanced system control and maximum pollutant removal are made simple. No modification to the core treatment process is necessary for expansion of performance.

Energy and Chemical Savings

Microbes use nitrate in the same way they use oxygen. Denitrification that occurs naturally in the IDEAL process reduces oxygen requirements and provides decreased operational energy cost. The alkalinity recovered during denitrification can decrease or eliminate the need for chemical addition that is needed in some plants so complete nitrification can occur.


Worry-Free Operation During and After Peak Flow Events

The IDEAL process has shown an excellent ability to maintain performance during and after heavy water surges. The IDEAL process also adjusts easily to varying degrees of organic loading. All process control options incorporate “storm mode.” This mode of operation initiates during extremely high flow events to eliminate the potential of reactor washout. The IDEAL BioReactor automatically resumes normal sequencing once flow decreases.

Minimum Operator Attention

The IDEAL process offers simple operation with operator commitment similar to traditional aerated lagoons.

Operating Data

Want to know what IDEAL could do for you?

Submit your RFP today and our on-staff professional engineers can help you size and design a IDEAL system to meet your wastewater treatment requirements.