Flooding

Serious flooding has occurred in most parts of New Zealand at some time or another, including in Whanganui.

Whanganui has a history of repeated flooding in low-lying areas, particularly adjacent to the Whanganui, Whangaehu and Mangawhero Rivers and neighbouring streams.

Climate change modelling tells us that heavier and more frequent downpours will cause localised or large-scale flooding in this area of the country.

Whanganui residents living or working near streams or rivers, on river banks or surrounding flats and floodplains should keep up to date about the weather and its effects on river levels.

The most significant flood event on record for Whanganui was in June 2015, when a combination of heavy rain caused simultaneous surface flooding as well as landslides around the city and in the lower, middle and upper catchments. This caused the Whanganui and our other rivers to flood.

This event was considered a 1-in-100-year flood. For an explanation of what this means watch the following video.

How to stay informed

• Call Waterline Whanganui Catchment - 0508 4 FLOOD (0508 435 663) for 24-hour river height and rainfall information in the Horizons region.
• Sign up to Horizons’ river warning alert system.
• Watch Horizons’ webcams (Whanganui River and coast).
• Overland Flow Path map – the predicted path stormwater takes in an unusually large rain event to get to the sea or stormwater network.
• Flood plain map.

Be prepared

People in at-risk areas should have a plan prepared for evacuating themselves, pets, livestock and important items or goods to a safe location.

Flooding may also impact our roads, so make sure you have supplies ready in your car in case you are stranded for some time. You may also be stuck at work, so prepare your workplace emergency plan.

How to prepare for an emergency – visit the Get Thru website.