Hartlepool Water owns and operates over 500km of water mains laid along every residentail street in the town and local villages of Hart, Elwick, Greatham and Dalton Piercy. These water mains are made of various materials including polyethylene, PVC, ductile iron and cast iron. Whilst the more modern materials are virtually maintenance free, cast iron pipes produce small amounts of rusty sediments that need to be removed regularly. Rust sediments are harmless to health but can cause unexpected discoloured water if water flows change suddenly. In general we flush are water mains regularly to remove rust sediments form the network