Residents demand traffic fix for 'horrendous' SA road

Adelaide's northern suburbs sign-maker Alan Sharkey has sold "thousands" of stickers with a simple, blunt message.

"It started as a joke — I had a friend drop by and the first thing he said when he walked through the door was 'f*** Curtis Road'," Mr Sharkey said.

The arterial road connects eight northern suburbs — and its daily congestion is a sign of what locals describe as a population growing too quickly.

Playford council said population projections showed 10 people a day on average would move into the area over the next 20 years, making it the fastest-growing local government area in the state.

During peak hour, Mr Sharkey said congestion on the single carriageway was "an absolute joke".

"It can be a struggle to get onto the road from my driveway," he said.

"Everyone you speak to in this area has their thoughts on [the road] … We need new housing, but we need the new infrastructure to support it."

Roads not built for the times, locals say

More than 10,000 people shared those feelings, and MacDonald Park resident Bronnie Coulter had the signatures to prove it.

Last month in state parliament, Sarah Game MLC tabled Ms Coulter's petition describing the traffic volume as "no longer safe" and urging the government to carry out road improvements.

The suggestions included dual lanes on Curtis and Womma roads, widening Main North Road, and building more exit lanes on the Northern Expressway, where cars can suddenly slow down from 110 km/h as motorists wait to get off.

There were also concerns about emergency services being bottle-necked, particularly during bushfire season.

"People couldn't get in fast enough [to sign] … they can't believe the growth has happened without improvements to the local roads," Ms Coulter said.

"It's quite horrendous during peak hour period and when people are picking up or dropping off children from school.

"These roads were built when it was semi-rural … and certainly did not cater to accommodate for this volume of traffic."

Playford's population grew from approximately 71,000 to 116,000 since 2006 and is projected to balloon to 184,000 by 2046, according to Australian Bureau of Statistics data.

At last month's council meeting, a motion calling on the state government to pause land releases and home approvals narrowly failed five to seven — despite unanimous agreement there was a problem.

Playford mayor Glenn Docherty said the region was doing the "heavy lifting" in population growth, with one in five new SA homes last year built in the council area and 1,100 further allotments received development approval.

"It's not just local traffic, it's traffic from further north that comes and uses our roads to get onto the Northern Expressway," he said.

"Making sure the infrastructure meets the needs of the local community, and future growth, is absolutely fundamental.

"That motion wasn't successful … but that doesn't mean that we're stopping our advocacy."

Development freeze unlikely

Ms Coulter's petition has been referred to a parliamentary committee with cross-party support, which would examine potential solutions and investigate their feasibility.

Planning Minister Nick Champion acknowledged residents' frustration but believed a development freeze would do more harm than good.

He argued it would "cost jobs", limit housing options, and sacrifice council rates which would otherwise be used for road upgrades.

Mr Champion blamed the traffic woes on underinvestment by previous councils, but said "the current administration is working with the state government".

He said the new roundabout and a train overpass on Curtis Road, together worth $280 million, would ease congestion.

"What we're seeing is the state and federal government investing hundreds of millions of dollars that will all aid duplication, and what we're doing is the work now to think about how you do the rest of it," he said.

Ms Coulter hoped more can be done.

"I do know we are in a housing crisis, but we also need to have the back up of the infrastructure," she said.

"I just hoping that we can see some action soon."