The ins and outs of filling the holes

THE ROADS and Stormwater Maintenance department does not want to be known as the best pothole fixer.

Potholes are a result of inadequate preventative maintenance and the preference is to have a maintenance protocol that results in as few potholes as possible.

The department, which falls under the Engineering Unit, is responsible for fixing and maintaining a network of blacktop roads totalling 7 682km and 1 420km of gravel roads. Duties include repairing potholes.

Dean Ashe from the department said it wanted to be proactive rather than reactive.

“Preventative action to maintain our roads is our biggest focus. If we are doing our job properly there should be minimal potholes. The department has a very proactive approach to road maintenance.

“The longer you leave a road to deteriorate, the more it costs to fix. If we carry out repairs early, and maintain it, costs are minimal. If a whole stretch has potholes, you will have to repair the whole road, which is costly.”

Part of its plan is for the CBD area, priority zones and arterial roads to be inspected once a fortnight.

Inspections

The rest of the network, including residential roads, is inspected once every six weeks. The work required is then scheduled to be undertaken by the departments.

Ashe said that department employees verify information about all types of complaints received at its call centre. They also collect information relating to potholes and relay details to depots via a works management system that schedules work on a priority basis.

This system allows the department to capture information about potholes in real time and feed the information to the depots for action within two working days. Hot asphalt is used to repair holes as well as other surface damage.

The council has its own asphalt plant and is partially reliant on private companies. It uses cold mix asphalt when hot mix is unavailable. Generally, this is only during the endof-year shutdown.

Road repairs are responded to within 10 working days.

The proactive approach is in keeping with that suggested by a comprehensive technical guide by the Council for Scientific and Industrial Research.

The guide states that while it is unlikely the formation of all potholes will be totally prevented, there are preventative and proactive steps to take to ensure fewer form.

The first objective should be to ensure that roads in need of bitumous reseal were done as soon as possible. Prolonging the resealing would result in drying of the surface.

Sealing of cracks is of the utmost importance. Their presence allows the ingress of water into the pavement layers, decreasing their strength and making them more susceptible to failure under loading.

Patching quality is often poor and many do not address the cause which results in repeated restoration.