Wet weather coming to east coast, South Island, coinciding with end of the school holidays

The NZ Transport Agency reminds drivers that heavy rain is forecast for the South Island’s east coast in the next two days. As well as the forecast heavy rain and gales in some places, potholes from the recent snow and rain mean drivers need to take extra care and build in time for long journeys.

'Because of the end of school holidays, there will be more cars on the roads and the possibility of slips and surface flooding with the heavy rain. Please slow down in these conditions and adhere to the posted temporary speed restrictions,' says Lee Wright, Transport Agency Journey Manager.

There are additional road work sites on the Picton to Christchurch Alternate Route currently – adding up to 45 minutes to the journey. Some of this work was delayed due to last week’s bad weather.

Potholes 101

Expect to see more work on our roads after wet or wintry weather as Transport Agency contracting crews fix potholes. Potholes form when water gets into cracks in the road. Vehicles drive over the cracks moving the water around and putting it under pressure. This movement and pressure opens up the cracks which eventually form potholes.

Potholes also form in very cold conditions when water gets into cracks and freezes. Freezing water expands and widens the cracks. When the road thaws the cracks are bigger which allows more water in and the cycle repeats itself until a pothole is formed.

The areas more vulnerable to forming potholes are:

  • In wheel tracks, particularly on roads with lots of traffic and/or lots of heavy vehicles.
  • Areas that have potholed before.
  • Wet areas.

Potholes can only be temporarily fixed in winter conditions so please be aware that some areas will become damaged more than once over winter. Permanent repairs occur in the spring and summer months. Drivers are welcome to report potholes on state highway (0800 44 44 49 or info@nzta.govt.nz).

How to stay up to date:

Keep up to date with the latest MetService forecasts and any watches/warnings at metservice.com(external link) or on mobile devices at m.metservice.com.(external link)