Road resealing

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Council maintains more than 1300 kilometres of roads across the city through its Road Reseal and Rehabilitation Program ensuring Lake Macquarie City has safe and high quality local roads. In 2020/21 the $9 million program includes more than 54 kilometres across 158 roads.

Resurfacing or resealing roads is part of Council’s asset preservation program designed to improve and restore the road pavement. Long term it represents sound economic and engineering practice, and is the most cost-effective solution to maximising the lifespan of our roads.

A road is made up of three layers: the surface, pavement and formation or subgrade. The surface of the road is the layer you travel on that declines over time, being exposed to and impacted by a number of elements. Each year a number of local roads require resealing to preserve the lower foundations and extend their useful lifespan by approximately 15 years.

Road resealing happens when the road pavement is in good condition, but the surface has deteriorated to a point where it requires intervention. It generally involves spraying hot bitumen over the existing surface, quickly tipping a layer of stone on top and rolling the stone into the bitumen. While Council appreciates this can be temporarily inconvenient for residents, it is an asset preservation practice to prolong the lifespan of one of our most expensive and important assets - road pavements.

Why is my street being resurfaced?

Council uses a Pavement Management System that models the condition of the road network and the road maintenance program. This helps council determine when roads need an intervention such as resurfacing or rehabilitation. When the surface of a road ages the bitumen becomes brittle and cracks. Cracks allow water to get in under the road and undermine the surface, leading to potholes and damaging the pavement below the surface. Resurfacing is a preventative to stop water damage before it occurs and avoid the cost of extensive repairs to the pavement.

This type of work occurs only once every ten to fifteen years depending upon the degree of deterioration, and is necessary to maintain the local road network for the benefits of all residents and road users.

Why was there maintenance works before sealing?

Prior to spray sealing Council staff and contractors undertake maintenance works to ensure the sprayed seal is successful in protecting and extending the life of the road pavement. This can occur on several different occasions depending on type of works, resources and machinery required.

Typical maintenance works involve some or all of the following:

  • Asphalt patching - replacement of a section of asphalt surface
  • Crack sealing - sealing with rubber around road patches or repairs to prevent water penetration into underlying pavements
  • Heavy patching - repair of small areas of damaged road pavement
  • Kerb and gutter repairs - patching or replacement of broken or damaged kerbs to prevent water penetration into underlying pavements
  • Subsoil drainage - installation of below-ground drainage to intercept seepage flows to protect the road pavement and seal from water damage
  • Sweeping - removal of debris and sediment from gutter to prevent contamination of the seal
  • Tree Trimming – Removal of low lying branches that will impede machinery operations
  • Weed removal - general weeding from gutter to prevent contamination of the seal.

Why are some streets treated with spray seal and others with asphalt?

Spray seals are used on low volume streets over existing asphalt surfaces to extend their life by providing a waterproof membrane. Where there is the presence of heavy vehicles or areas of high stress on the road pavement, such as in intersections and cul-de-sacs, asphalt may be used as the resurfacing treatment. Asphalt treatments are expensive and only used where spray seal treatment may not be suitable. The most cost effective resurfacing treatment has been selected for your street to preserve the City’s road assets.

Why are there loose stones on my street?

Your street has likely been spray sealed. This requires coverage of aggregate to be laid over a film of bitumen to provide a hard wearing, skid resistant surface. In order to ensure all the bitumen is covered, a little more aggregate is placed than may actually stick to the surface. Loose aggregate is a temporary issue only and is left on the road surface for up to three days, before being swept off and recycled. The loose aggregate gets moved around during this time because of traffic and may collect on the road or in gutters giving the appearance of piles of aggregate. Council will generally sweep the street up to three times in the initial settling-in period of four weeks.

Why is the new surface so rough?

Initially, spray seal road treatments have excess stone applied and the surface can be rougher than the original seal. Resealing renews the texture in the road that would have been there originally with the new seal applied becoming smoother over time.  Over the course of approximately 12 months the raised sections of stone will impregnate into the surface and the general wearing surface texture is reduced. 

Why use spray seal for resurfacing?

Spray seals provide a cost effective flexible layer over existing road surfaces or new pavements, to prevent water undermining the road pavement and provide a long road life, with nearly 70% of Lake Macquarie roads have been sealed in this manner.

This treatment involves spraying a film of bitumen across the road surface to seal minor cracking. The majority of Council’s spray seals contain a rubber compound to improve flexibility and reduce cracking. Bitumen based treatments are also known as flexible pavements because they can move and spring back under stress without cracking.

This is essential to prevent traffic damage, to prevent water undermining the road pavement and provide a long road life. Approximately 90 per cent of Australia’s sealed road network area is surfaced with sprayed seals.

The seal has come off in parts of the road and outside my driveway?

The film of bitumen sprayed during the spray sealing process needs to cure after the aggregate is spread and rolled. During warm weather, a new spray seal is susceptible to scuffing. Scuffing occurs when vehicles back out from driveways and turn the steering wheel whilst stationary or stop abruptly. If this occurs on warm days, the aggregate under the car tyres can strip, exposing a thin film of bitumen on top of the aggregate. This can be avoided by not turning the steering wheel while the car is stationary or braking heavily.

The bitumen film and loose aggregate can be sticky on warm days. Scuffmarks are not normally damaging to the seal and they are not a defect in the seal, they are an unwelcome but expected result of traffic movements on this type of surface. These marks become less frequent as the bitumen cures and they will eventually stop occurring.

Why should I cooperate? This is inconvenient.

The cost of maintenance works such as these are based on time to complete the works. Allowing our contractors full and unhindered access to your street will ensure their time is used efficiently and that cost and inconvenience is minimised. For spray seal the road is out of service for approximately 15 minutes before vehicles can drive on it again.

If you have any concerns or questions about access to your driveway during work please do not hesitate to approach the traffic control staff.

You can read more about kerbs and gutters here(PDF, 109KB) .