Nereda design capacity

  • 2262 m3/d
    Dry Weather Flow
  • 1005 m3/h
    Peak Flow
  • 13500 PE
    PE (PE = 60 gBOD/d)

Project facts

  • Client
    Waterschap Vechtstromen
  • Location
    Vriezenveen, The Netherlands
  • Period
  • Wastewater
  • Project type
  • Process configuration
    Pre-treatment + Nereda

About Vriezenveen Nereda® WWTP - The Netherlands

Vriezenveen is a town in the Dutch province of Overijssel. It is located in the municipality of Twenterand, about 7km north of Almelo in the Netherlands.

The challenge

The upgrade of the municipal wastewater treatment plant (WWTP) at Vriezenveen in the Netherlands marks another chapter in the Nereda story. The plant serves a population equivalent of 13,500 people with equipment and technology that dates from the 1970s. Following the success of the hybrid Nereda plant in Vroomshoop, Royal HaskoningDHV has been engaged to build the second Nereda treatment plant for the Vechtstromen water authority at this site.

The solution

Water Board Vechtstromen is an innovative organisation and attaches great importance to the recovery of energy and raw materials from wastewater. The 1970s purification system has been replaced by a sustainable, modern installation that can easily be adjusted online via an Aquasuite Nereda Controller. The basic operation of the original process and the new Nereda installation is largely the same, with dirty sewage water broken down and cleaned by billions of bacteria. However, only two Nereda reactors of 1700 m³ have been installed at Vriezenveen, which simplifies and accelerates the purification process. This saves on the site space required, because the aerobic bacteria form compact mud granules, allowing several treatment steps to be completed simultaneously.

The outcome

Compared to the old installation, the new treatment process reactors occupies less than half of the original site. The new installation has the capability to extract more raw materials from the sewage water produced by 13,500 people, against lower operational and energy costs. Running at peak flow, the site can process 1000 m³/hour with a capacity of 24 MLD. The Nereda plant is operational and purifying wastewater from Vriezenveen.



  • Updated technology to meet current standards

  • Accelerated process

  • Higher-quality effluent 

  • Automated adjustable control

  • Increased capacity