The Master Plumbers Association says plumbers are working around the clock since the Canterbury earthquake.
It says there will be no quick fix and repairs to plumbing in Christchurch will likely continue well into next year.
Association chair Mark Whitehead says it's an extremely challenging situation because most plumbing problems are invisible, being buried beneath the ground.
He says many problems such as cracked pipes won't show up straight away and he would advise people and businesses to arrange checks as soon as practical.
Mr Whitehead warns homeowners to avoid offers from unregistered plumbers offering to fix problems.