Uneven Peat Road Surfaces – FAQs
Almost half of all peatlands in New Zealand are located in the Waikato District. These peatlands have taken over 18,000 years to form and are up to 11 metres deep.
Many roads in the Waikato, and several in Waipā, are constructed on top of peat soils.
During dry months of the year, these soils shrink due to a lack of moisture. This shrinkage causes road surfaces to settle unevenly, creating bumps, cracks and ruts in the road.
This is a common issue around the Waikato region and is more pronounced following dry summer and autumn seasons.
In Waipā, Collins, O’Regan and Rukuhia roads in Rukuhia, and Storey and Cambridge roads between Te Awamutu and Cambridge are generally the most affected. However, in past years this has also been an issue in isolated locations on other roads around the district.
Council closely monitors these roads and will intervene where required to erect warning signs and speed restrictions or to smooth the surface with asphalt when needed.
Please drive to the conditions, be vigilant and report any issues to 0800 WAIPADC (924 723).
Our long dry summer and dry autumn have created the conditions for peat soils to dry and shrink significantly this year. Roads across the peat settle unevenly with this shrinkage creating cracks, ruts and wavy bumps in the road surface.
Collins, O’Regan and Rukuhia roads in Rukuhia, and Storey and Cambridge roads between Te Awamutu and Cambridge are generally the most affected. However, in past years we have also seen this issue in isolated locations on other roads around the district.
Yes, the Waikato contains about half of New Zealand’s peatland. Waikato peatlands have taken over 18,000 years to form and are up to 11 metres deep.
Settlement and loss of the normal road shape can be a hazard, particularly for truck and trailers with a high load or vehicles travelling at speed. The most important thing is for drivers to slow their speeds and drive to the conditions over the winter period.
Council staff and contractors are monitoring the settlement and intervening where required to erect warning signs and speed restrictions or to smooth the surface with asphalt when needed.
Peat soils are very deep and it is not economic to excavate them out and build a normal road foundation. Council manages the situation by allowing to reshape the surface of peat roads every 5-20 years, but exceptionally dry years mean more repair work. Landowners beside peat roads can assist by not deepening or creating new drains in their properties next to the road as this serves to speed up peat shrinkage and road damage.
Drivers will see signs and speed restrictions in place on Storey and Cambridge Roads already. Others may be required soon as the peat will continue to shrink for some months until normal moisture levels return to the soil. Drivers need to be aware that road workers may be on these roads frequently making temporary repairs until full smoothing can be completed.
It is possible that some sites will have speed restrictions until September or October. We need the shrinkage of the road to slow down and for summer temperatures to return to allow chip sealing of final repairs
Please call or customer service team on 0800 WAIPADC and report it. While our staff may be aware of the location and issue, at times cracks and bumps can appear quickly over a few days so we need to hear about any issues as drivers come across them.