A new road maintenance tool developed by two University of Auckland students will bring savings to Central Otago ratepayers.
Central Otago District Council's roading manager Julie Muir said the council hosted two engineering students as part of their study in unsealed road maintenance for two weeks last year.
Vivienne Jones and Billy Rodenburg looked at unsealed roads and past, present and potential gravel sources in the district and their effect on gravelling and grading cycles, she said.
The students developed a ''mathematical model'' which took gravel pit data and measured it against the cost of gravelling and the life maintenance costs for different pit materials, to find the most ''cost-effective outcome'' for each road.
Previously the council had made a judgement call based on the gravel material, its location and the costs associated.
Unsealed roads require maintenance and regravelling, with some roads requiring more than others depending on the volume of traffic.
The students used the model to do a case study on a road and discovered the council could have saved 25% over the life cycle if an alternative pit had been used, despite the upfront cost being higher, she said.
The council would use the new tool for its 2015-16 gravelling programme to find the most cost-effective options for each road.
The council spends almost $1.5 million on gravelling a year.
''The outcome of this will contribute towards a national guideline for decision making on unsealed roads and is likely to be adopted by the wider industry.''
The Central Otago district has one of the largest unsealed road networks in New Zealand, with 74% unsealed.
The district has more than 1850km of roads, 1376km of gravel roads, 509km of sealed roads, 176 bridges, and 151km of footpaths.
