A large water supply utility in Romania, covering a water network of about 400 km and a population of approximately 200,000 people, decided to replace its old pipes with new PE pipes using AVK gate valves as well as new and modern solutions for pumping and pressure regulation. The modernisation and extension of the water and wastewater network reduced the utility’s water loss by more than 10% and resulted in big savings on operational costs. The problem with the previously used metal seated gate valves was that they were mounted in concrete wells and often caused problems in relation to shut-off tightness. In contrast, the newly installed AVK resilient seated gate valves have been mounted directly underground and feature rubber which absorbs impurities and are thus able to shut tightly for a lifetime. The Romanian water supply utility also installed AVK air valves which furthermore had a positive impact on the utility’s network as it led to both a reduction in hydraulic problems and a decrease in energy consumption needed for pumping.