LOOKING FOR WORK: Two sex workers touting for business on Ferry Rd in the Christchurch suburb of Phillipstown on Wednesday night.

Christchurch prostitutes aren't letting natural disaster prevent them from plying their trade on the streets despite the dangers of aftershocks in the city.

However, the national office of the organisation that lobbies for sex workers, the New Zealand Prostitute's Collective (NZPC), said street walking had become riskier than ever in the wake of Tuesday's devastating quake.

Yet early yesterday there were signs the sex trade is returning to the streets of Christchurch, albeit shuffled from the cordoned CBD.

In the suburbs of Phillipstown and Waltham, living conditions are strained.

Water supplies are severed, electricity is intermittent, roading is shattered, mud from liquefaction is everywhere and buildings are collapsed.

Yet after dark there is an element of vice.

Teetering in boots, two women picked their way through mud and rubble of collapsed shops in Ferry Rd, towards the visibly leaning Lancaster Park Hotel.

"Do we look pretty?" one, dressed in a skimpy red corset, asked. "Two prostitutes walking down the street."

Questioned as to the safety of walking the streets, she was blase.

"You're working too aren't you; we have to live."

NZPC's Christchurch regional co-ordinator, Anna Reed, said it was a concern sex workers were standing in the shadow of potentially unsafe buildings as the city was shaken by aftershocks, but said the shattered CBD had "left them with no outlet".

Like the collective's Christchurch branch office, which is extensively damaged, inner-city massage parlours were locked behind the cordon, damaged or destroyed, she said.

The organisation had a "text alert" scheme in place and would use that to send a message out to sex workers, she said.

However, for some the potential loss of earnings meant many would take to the streets regardless of risk.

The reaction NZPC's National Office in Wellington was one of surprise yesterday.

"If I was down in Christchurch I certainly wouldn't be out trying to work the streets at the moment," spokesman Calum Bennachie said.

Meanwhile, a few blocks away in Nursery Rd last night, two women offered a very different service – free water.

Volunteer Abigail Milesi said after four hours she was looking forward to a cup of coffee.

A steady stream of people had been stopping by all night, she said.

"I just wanted to help. People just come and fill bottles and buckets. It's not good to drink unless they boil it."

For some people in the neighbourhood, life without the basics was getting hard, she said.

"One lady has got a baby. It's real difficult for her."

But amid the struggle she got some reward from hearing amazing stories of survival, she said.

"He was in the Eastgate mall when it collapsed. He was getting these old people out. You would get enough stories here to fill the newspaper."