Canterbury's Selwyn District sees population explosion, but is its growth sustainable?

The Selwyn District just south of Christchurch used to be a sleepy rural settlement.

Now it's going through a construction boom and a population explosion. What makes it so attractive? Let's just say: New four-bedroom home with double glazed windows for $550,000.

Selwyn is both liveable and affordable - but at the rate it's growing is it sustainable?

Rolleston - once dubbed the town of the future - is now living up to the hype.

Just 20 minutes from Christchurch, it's expanding by the day. And it's not hard to work out why.

"To be able to buy a four-bedroom house on 600 square metres, brand-new, double-glazed for $550,000, which is where prices have sort of sat for the last ten years, certainly means that that is an affordable price bracket for lots of people," Selwyn Mayor Sam Broughton says.

But before there were lots of people it was a small, sleepy country town on State Highway 1.

"It had stayed relatively stagnant since the '70s. And the population had grown very very very slowly and now it's growing exponentially," urbanist James Lunday says.

But fuelled by post-earthquake relocation it's now filled with young families looking to get bang for their buck.

"This house we wouldn't be able to afford in town and that was the thing that really ticked the boxes," Rolleston resident Rebekah Campbell says.

But for Campbell and her growing family, it provides much more than just affordable housing.

"It's been a really nice move, particularly moving from an older neighbourhood where you just live singularly by yourself to actually feeling like you're part of the community," Campbell says.

Kevler Homes is one of many building companies cashing in on that dream.

Rolleston once represented 15 percent of their business, now it's more like 60. The demand is so strong they're struggling to keep up.

"Like we will put a listing on Trade Me, and in the past you know we would get a few hundred views, but now and after a couple of days we're getting thousands of views," general manager Rex Huang says.

"I would say 30 or 40 enquiries and probably 20 or 30 people interested in two or three days and it's very hard for us to choose."

One of the most recent section releases in Faringdon even crashing the website.

"The quality of the housing for the price is really high, and the biggest surprise is that it could and should be growing quicker," Lunday says.

"The target market isn't Christchurch in my opinion, it's Auckland - you know you can't buy a garage in Auckland for the cost of a very nice house here."

Lunday has been following Rolleston's fairytale - he's not its biggest fan.

"This is classic 1960s American suburbia," he says.

"I arrive here and this street is no different from that street, no different from the street over. If I came home slightly tipsy one night I might go in the wrong house."

While Rolleston is at the heart of the boom, other centres in the wider Selwyn District are also in hot demand.

"In 2001 Selwyn was 16,000 people. Here we are in 2021 and we're over 70,000 people so 55,000 in 20 years," Broughton says.

"It's been pretty dramatic growth and we're planning at the moment for another 20,000 in the next ten years."

With the ability to continue to grow out, not up, the mountains are the limit - but should they be? Each home comes at the expense of farmland.

"As we move forward I think we need to protect our versatile soils," Broughton says.

"We can't just have towns that continue to sprawl across the plains."

The focus now for the council is future-proofing Selwyn, balancing the demand for more housing and infrastructure with the need to protect farmlands and build community.

"At the moment working as a council to think about what does Selwyn look like at 300,000 people. That's probably beyond my lifetime, although who knows how fast things grow," Broughton says.

"It should actually have a masterplan for how it's going to grow sustainably," Lunday adds.

Then it truly will be the town of the future.