Phill Thomass, Rotorua Lakes Community Board Chairperson, spoke to Local Focus about the open day at the new Rotoiti water treatment plants.
"This plant is really high-end, the best we could get in terms of tech," Thomass said.
"Plants used to just be for treating bacteria, but this plant strips out all nitrogen and phosphorus, we don't want those going back into our lakes.
"When we developed this, communities had concerns about other things in sewage, some are on dialysis and cancer treatment so we put in extra filtering for that."
Touring the new plant has changed the minds of many residents who were unsure about the project, he said.