Potholes: your questions answered in new Port Stephens Council education series

The timely launch of the series on the council's website and social media pages, coming as the Port's roads are pockmarked by potholes following heavy rain and flooding events in the past five months, will provide information on the process of building roads and answer questions on key issues such as potholes, reseals and rebuilds.

"Two of the most frequently asked questions we get are: why do we only do a temporary fix on a pothole and why reseal a perfectly fin road when there's a spot further down that has potholes everywhere," Greg Kable, the council's group manager of facilities and services, said.

"We know when we put coal mix in a pothole that at some stage it's going to blow back out and that it's only a temporary fix.

"What we want to get across is that we know it's a temporary fix but when it's raining and we have extended periods of wet weather it's really is about managing risk to drivers.

"The second biggest question people always ask is 'the road in front of my place is falling to pieces yet just up the road they've done a reseal when there's nothing wrong with it. Why?'

"That's exactly what happens. To do a reseal the road needs to be in good condition. All a reseal does is put a weather proof capping over the top of the road. Once it starts to pothole or fall to pieces it's too late for a reseal."

Mr Kable said the education series would explain what is required to permanently fix a pothole and a road, the differences between a cold and hot patch fix for potholes and when they can be used, and provide more information the council's road management and maintenance program.

The council manages more than 800km of roads across the LGA.

"We invest more than $1.6 million into the management and maintenance of our road networks each year," Mr Kable said.

"We have a rolling schedule of road maintenance and although we'd like to reseal about 10 per cent of our networks each year, we do less than 2 per cent due to a lack of resources.

"Potholes need to be repaired as quickly as possible however, after heavy rain, we get lots of potholes and need to prioritise which ones get fixed first.

"To fix a pothole properly we need to reseal or rehabilitate the road and we just don't have the resources to do this on every road. Outside of this we have to use temporary measures to fix potholes.

"When we have constant rain, like we do now, a cold patch is the best method to use. We need to fill as many holes as we can to avoid risk to our community. If it's raining, a hot mix won't work."

How do potholes occur?

Sometimes due to general wear and tear, faults in the pavement surface but more often than not, it's weather events that cause significant pothole damage.

Over time, the road seal deteriorates due to general wear and tear - this can lead to small cracks in the seal which can increase over time and cause an opening or pothole. The size of the pothole is reflective of the quality of the subgrade under the road - good quality roads with high quality subgrade have less potholes than those roads with poor quality subgrade.

Potholes increase significantly in bad weather when water gets in the cracks in the seal. This undermines the subgrade and simply creates a hole in the surface of the road pavement. As rain continues to fall, it expands the hole - at the same time, traffic continues over the surface causing more damage, increasing its size and causing more dangerous potholes.

Prioritising potholes

Potholes need to be repaired as quickly as possible however, after heavy rain, we get lots of potholes and need to priorities which ones get fixed first.

We have a very specific criteria for determining the risk associated with each pothole which includes things like the traffic volume and whether the pothole is in the middle of the road, to the side and so on.

When our road crews head out to fix a high risk pothole, they also fix many smaller, less risky ones nearby to save time and money. We always try to get to the most dangerous potholes first.

Why not fix it properly?

To fix a pothole properly we need to reseal or rehabilitate the road and we just don't have the resources to do this on every road. Outside of this we have to use temporary measures to fix potholes. There's two ways we can do this:

Cold patch: When we have constant rain - like we do now - a cold patch is the best method to use. We need to fill as many holes as we can to avoid risk to our community. And if it's raining, a hot mix won't set properly.

After a major storm event - we just need to fix the cracks - a bit like if your roof leaked, you need to patch it immediately to stop more water getting in and damaging the rest of the roof.

A cold patch really is a quick fix - a surface level fix - they aren't as effective as a hot mix and don't last nearly as long. But again, it's all about reducing the risk to our community. We know it won't last a very long time, but if we don't get out as quick as possible, we also know it won't take long before more damage occurs underneath and we are up for more money and more maintenance.

Further repairs - such as a hot mix repair - will be needed only a short time later.

Hot mix: We use hot mix when we want to repair substantial pot holes, in dry weather and know the repair will last. The pavement around the pothole is excavated and then filled in and sealed with hot asphalt.

This type of repair addresses the underlying problems that caused the pothole and prevents more damage from occurring.

They cost more up front, but they end up costing less in the long run as no further repairs will be needed in the short term.

How do you know where the potholes are?

Our pothole program is based on calls from customers, reports by councillors and our regular reviews of the roads.

We also have a roads inspector who travels our road network regularly and reports on pothole locations, size and associated risk.

We also have information that comes in from the public.

This is really important and the more data we have the better we can manage our road network to ensure it is safe for our community.

Report potholes here: authorityapp.portstephens.nsw.gov.au/eservice.

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