Nereda design capacity

  • 750 m3/d
    Dry Weather Flow
  • 1135 m3/h
    Peak Flow
  • PE (PE = 60 gBOD/d)

Project facts

  • Client
    Aqua-Aerobic Systems, Inc. at the Four Rivers Sanitation Authority
  • Licensee
    Aqua-Aerobic Systems, Inc.
  • Location
    Four Rivers Sanitation Authority, Rockford, IL
  • Period
  • Wastewater
  • Project type
  • Process configuration
    Grit Removal and Screening. Various tests with cloth media filtration are scheduled.

About the Rockford Nereda® WWTP

To introduce aerobic granular sludge to North America and to test particular conditions found in the United States, Aqua-Aerobic Systems committed to building a demonstration facility using Nereda technology. This demonstration reactor is constructed close to Aqua-Aerobic Systems’ headquarters in Rockford, Illinois at the Four Rivers Sanitation Authority – about an hour west of Chicago.

The Four Rivers Sanitation Authority serves 240,000 people across 88 square miles of Winnebago County, in the US state of Illinois. The plant is a conventional activated sludge system. At the plant Aqua-Aerobic Systems operates its Research & Technology Center, where the company tests its new products. In 2017 the Nereda demonstration facility was constructed, as an expansion to the Research & Technology Center.

The Rockford demonstration facility marks the technology’s introduction to the United States and Canada, with the installation of a 200,000-gallon per day (757,000 liters) reactor.

In addition, the plant will also provide a North American site with the ability to grow and store seed granules for future plants in the US, to accelerate biological nutrient removal during the commissioning of new plants.

The demonstration facility gives essential, first-hand information to visiting American and Canadian engineers and plant operators about the advantages and savings that can be made by using Nereda technology. The Nereda technology has been developed in the Netherlands by Delft University of Technology, the Dutch Water Authorities and Royal HaskoningDHV. In the US and Canada, Nereda will be marketed under the brand of AquaNereda® aerobic granular sludge technology.

The demonstration facility allows Aqua-Aerobic Systems to further the development of the technology and test particular applications commonly found in US water treatment plants.


  • A sustainable solution

  • Chemical free process

  • Significant cost savings

  • Increased capacity and efficiency

  • Future-proof compliance