Floodstop consists of red and white barrier units that sit on a foam gasket and lock together with a key unit. Because they are individual units they can be configured to any length or shape.
The red barrier units are pre-filled with water to hold the barrier in place; the white units have self-filling holes at the bottom which fill with flood water during a flood and drain as the water recedes.
Floodstop was developed by Simon Phelps at the University of Bournemouth.
"It's been around for about nine years, but four of those years were spent in development. It's currently being used in Britain, Europe and the United States," Mr Rau said.
Floodstop isn't being manufactured in New Zealand yet, but Mr Rau said production of it would begin soon in Palmerston North.
Mr Rau said the company decided to launch Floodstop in Whanganui because it's a part of the country that is very familiar with floods.
"And the reality is that we're not going to get fewer floods, and we need to look at strategies for dealing with that."
There's a personal connection too as Mr Rau has close family ties to the district.
The public demonstration was attended by members of local iwi, councils and civil defence, the fire service, Department of Conservation staff, and interested individuals who live in flood-prone areas.
Peter Bedborough is an Anzac Parade resident who was flooded out in the major flood of June 2015.
He came along to see whether Floodstop could be used on his property.
"It's very interesting. It may have stopped my house from flooding in 2015," Mr Bedborough said.
Anthony Edwards, from Whanganui District Council's emergency management, said he thought Floodstop was a great product.
"It would be a good alternative to sandbags, which are a pain."
Mr Edwards said he believed Floodstop would ideally be used to help protect businesses along Taupō Quay.
"There would be no point using it on Anzac Parade - the water there would just go straight over the top of it."
Mr Edwards said the only issue with Floodstop would be who would pay for it.
+To find out more about Floodstop visit the website.