Auckland floods: warnings about health hazards in flooded homes

​Health experts are warning residents to be careful of returning to their waterlogged homes because of health hazards such as mould and contamination.

More than 100 homes have been red-stickered this morning, meaning they are seen as too dangerous to enter.

Dr Mikael Boulic, Senior Lecturer at Massey University says floodings are the perfect conditions for mould to grow, especially in warm summer weather.

He's urging residents to take care and says they shouldn't go in if they have skin or respiratory conditions.

"Before returning to your home, first wait for the green light from Civil Defence. Then put on as much protection equipment as possible (gloves, mask, disposable overalls).

"Mould is very tricky because you clean what you see, and don't clean what you don’t see. Mould grows according to temperature and relative humidity and often it is invisible. ​

"If you go back to a flooded house, be careful, there are a lot of potential hazards. Know what you are doing.

"It could be a very unhealthy environment if there is sewage overflow in the floodwaters."

Boulic says use an air conditioner, dehumidifiers "and every fan you own" to help dry out the house as soon as possible.

The health hazards were emphasised by Dr Lucy Telfar Barnard of Otago University.

"Often if we've got dampness in the home from a leak, the solution is simply drying it out. But this is a different situation, because floodwater tends to be contaminated with sewage and other nasties.

"If you have carpet or some kind of layered flooring, it may have to be replaced. That's because it's not just about the surface contaminants, but also what's sitting underneath - and the smell that will not go away unless you do that.

"In the short term there's also concern about mould. People with respiratory conditions should make sure they're staying somewhere dry, because mould growth could exacerbate their condition.

"Something people might not think to do straight away is to check the electrical safety - water and electricity don't play nicely."

There was also advice for renters whose homes have flooded and whether they have to continue paying rent.

Dr Sarah Bierre of Otago University says tenants need to the landlord know of any damage and landlords should check in with tenants.

"It’s the landlord’s responsibility to pay for repairs to the house. It’s important the house is dried out properly to prevent mould growth and that damaged or contaminated fixings are replaced.

"If just part of the house is uninhabitable or destroyed the rent should be reduced while it is fixed. No rent should be paid if the tenant has to leave while repairs are done. In some cases, it might seem better for the tenancy to end."​