-
Original article in Dutch, by H2O in collaboration with Water Alliance, can be found here!
-
Click here to read more regarding the project at WWTP Enschede!
The wastewater treatment plant (WWTP) in Enschede, operated by the Vechtstromen Water Authority, plays a key role in the demonstration phase of the national UPPWATER program. The water authority, together with Nijhuis Saur Industries and Witteveen+Bos on behalf of the CLC Water consortium—complemented by companies Jotem Water Solutions, NX Filtration, and Van Remmen UV Technology (all members of Water Alliance)—will be testing purification technologies in the coming years aimed at removing pharmaceutical residues from wastewater.
This content is produced by Water Alliance
Enschede: a strategic hotspot
The choice of Enschede as the test location is no coincidence: according to a long-running monitoring program by STOWA, the city is a clear hotspot for pharmaceutical residues.
“In the hotspot analysis, Enschede lights up red,” says Rob Sjerps, project manager at Vechtstromen Water Authority. “We’re dealing with high concentrations of pharmaceutical residues in the wastewater due to heavy urban inflow, with numerous healthcare institutions and a university hospital.”
Starting in Q2 2026, a demo installation capable of processing 50 cubic meters per hour will be tested for a period of 18 months. A total of four pilot setups will be built, using combinations of UV/ozone, nano- and ultrafiltration membranes, and various pretreatment techniques. The goal is to determine which combination is the most effective, sustainable, and applicable for the intended full-scale installation.
More than just technology
“It’s not just about the technology,” Rob Sjerps emphasizes. “We also want to learn about cost development, management, public acceptance, and scaling up. Our unique process approach focuses on efficient product development, where the demo design is continuously tested against the consequences at full scale.”
The technologies tested in the demo must achieve a minimum purification efficiency of 80%, the benchmark set by the future European Urban Wastewater Directive. “Some of the tested technologies already reach up to 95%, but we have to assess whether that’s truly necessary.”
Monitoring and technical challenges
The effectiveness of the techniques will be measured through extensive monitoring, evaluating factors such as temperature effects, membrane selection, and pretreatment options. One major technical challenge is the treatment of the concentrated residual stream left after filtration.
“Sending it back to the WWTP isn’t an option—that would just concentrate the problem,” says Sjerps. “We’ll have to come up with a solution within the project.”
After the demo phase, a full-scale installation is planned by the end of 2028, capable of processing 500 cubic meters per hour. This step will be crucial for achieving Vechtstromen’s strategic goals in water quality, innovation, and sustainability.
Innovative collaboration model
One unique aspect of the project is the partnership with Nijhuis Saur Industries, established through a European tender using a “competitive dialogue” approach, allowing market parties to contribute ideas before the request for proposals was finalized.
“This way, we developed the most suitable concept together,” says Sjerps.
Interest from Vitens
Meanwhile, Vitens, the Dutch drinking water company, has shown interest in the developments in Enschede. According to Sjerps, the company is exploring the potential use of treated wastewater as a source for drinking water production.
“Vitens is paying close attention to what we’re doing here,” he says. “We may eventually need to make additional investments to produce marketable products such as drinking water or ultrapure water.”
This idea aligns with broader national ambitions to close water cycles and use available resources more efficiently.
“Especially during dry periods, when pressure on groundwater reserves increases, reuse of treated wastewater could play a vital role,” says Sjerps. “The condition is that the purification technology must meet the highest standards in terms of efficiency and safety. That’s why the demo pays close attention to the quality of the end product.”
UPPWATER: accelerating through chain collaboration
UPPWATER stimulates the economic growth of the Dutch water technology sector. It’s a 10-year program (running through 2032) that promotes deeper collaboration across the innovative water tech chain, enables pilot and full-scale demonstrations, and removes barriers to speed up global market scaling.
The program has a budget of over €340 million, of which €135 million is funded by the Dutch National Growth Fund.
“The government plays a crucial role by supporting programs like UPPWATER,” says Ronald Wielinga, COO at Water Alliance, one of the program’s partners.
“Through projects like UPPWATER, we not only gain more knowledge but also better leverage that Dutch expertise to solve water and environmental challenges in our domestic market. And we connect these solutions with other players both nationally and internationally.”