In Cramlington properties, hidden leaks often trace back to corroded original supply pipework reaching the end of its service life in 1960s and 1970s housing in eastfield and northburn or leaks spreading unnoticed across the town's flat topography instead of pooling visibly. Watch for a higher water bill, damp or warm patches on the floor, a hissing sound near pipework, or lower water pressure. Properties such as 1960s and 1970s new-town housing with pitch fibre pipes, modern housing estates, and commercial and industrial units are worth checking often, since a leak can run for weeks before it shows.