We were tasked with locating a leak at this medium sized, industrial site (former MOD) and it was reported there was no water flow/pressure to a section of the site, and the meter was spinning rapidly. The water meter is only 25mm diameter, but it serves a 6” main around the site. The meter was showing a loss of 3600 litres per hour. We checked for leak noise around the site surveying all fittings such as stop taps, valves and fire hydrants. There was minimal leak noise only on 3 of the fittings and this was not surprising bearing in mind the restriction caused by the small sized water meter feeding the site. We used RD7000 equipment to trace the pipe route at the premises then we surveyed the mains using an” Ecologics Leakfinder Correlator”. The correlator gave a positive indication approximately 4m from one of the valves. There was little to no surface leak noise at the indicated leak site but it was marked up for an exploratory excavation. A call from site staff the following week confirmed that the leak was where marked and it proved to be a circum fracture of a 6” cast iron main.
