A leak found in the water distribution network of NUPI Industrie Italiane plant allowed us to compare cast iron and plastic materials for the transport of water. Once the hatch was opened, the cast iron T-fitting was found broken, as shown in the photos. The distribution line was promptly restored and the system was switched on again. Both HDPE pipe and cast iron T-fitting worked underground for 20 years with main water at 8 bar pressure. The cast iron T-fitting shows obvious signs of wear and tear, while the plastic pipe still meets its original performance specifications.