Leak Detection South Christchurch and Port Hills

Leak detection south of the city, from the river flats to the Port Hills

This part of Christchurch splits into flat and steep, and leaks behave differently on each. Spreydon and Beckenham sit on flat former swamp and farmland, with early 1900s homes, villas and bungalows on timber floors. There the search usually starts under the house, and Beckenham's big street trees mean roots near an old supply pipe are worth ruling out. Where an original home has had a second house built behind it, a shared supply pipe is also common, and we test each owner's branch on its own.

Up the hill it changes. Cashmere and Lyttelton homes often have long supply pipes climbing steep sections, and water escaping from a pipe on a slope tends to run downhill before it surfaces, so the soggy patch can be well below the actual fault. Hill homes draw from council reservoirs or tanks that hold the pressure even, but ground movement in 2010 and 2011, including the mass movement areas GNS identified in Cashmere, stressed buried pipes. We trace the pipe route first, then listen along it uphill of any wet ground.

Halswell and Hoon Hay add newer housing and bigger blocks. Halswell's Longhurst and Knights Stream subdivisions are mostly concrete slab homes with pipe hidden in the floor and walls, while Hoon Hay has semi-rural properties toward the valley with longer runs from the boundary. For those, isolating sections of pipe and pressure testing each one saves digging a whole line, and thermal imaging handles the slabs.

Local tip: On a Cashmere or Lyttelton section, look for wet ground or unusually green growth below the line of your supply pipe, not just above it, because escaping water heads downhill.