Details
Last Updated: Tuesday, 17 December 2024 14:29
Grading plant on unsealed road

We maintain approximately 3,300 kilometres of gravel roads.

Our goal is to keep our gravel roads safe and trafficable within the constraints of a limited budget. The condition of gravel roads can change quickly, and drivers need to be vigilant and drive to the conditions.

How we create the maintenance program

To create our maintenance program we complete regular inspections of our road network to assess the condition; looking for issues such as potholes, corrugations, rutting, scouring and loss of surface material.

How we prioritise maintenance works for the roads

There are a few considerations that influence how we prioritise the order, and how often roads are graded, such as:

  • frequency and number of vehicles travelling on the road
  • type of vehicles using the road
  • the severity of the conditions
  • location/s of the damage/s
  • how the road services the greater network.

Maintenance program activities

The primary maintenance activities on gravel roads are:

  • maintenance grading (light, medium and heavy)
  • gravel road resheeting

Maintenance grading levels

  1. Light maintenance grading involves light trimming by the grader to allow existing material to restore reliability.
  2. Medium maintenance grading includes the removal of existing grass and vegetation, the use of water and compaction and the treatment of drains where applicable.
  3. Heavy maintenance grading involves the removal of existing grass and vegetation, scarifying/ripping the existing surface with grader tynes, the addition of imported gravel/material in isolated areas, the use of water and compaction and the treatment of drains where applicable.
  4. Gravel resheeting involves importing, laying and compacting a layer of gravel (usually 100mm thick) to a section of road to replace pavement that has worn away. The table drains are generally cleaned as part of this operation. Gravel roads may need to be resheeted every seven to 20 years depending on the rate of gravel loss.

Program challenges

While we exercise our best efforts to keep our gravel roads in reasonable condition, various challenges can affect the delivery of the program requiring us to adjust it accordingly. Some of these challenges include:

  • weather events causing damage to different areas
  • extended dry periods
  • feedback from customers with changing conditions
  • budget allocation
  • water supply (this is required to compact the gravel properly).