Bellingen Shire Council has recently completed trialling a dust suppression treatment based on the Otta Seal concept on a 600m unsealed section of Summervilles Road Thora. The site was selected due to the significant dust issues that occur periodically and the effects of the dust on driver safety and local horticultural activities.
The process involved the placement of a modified bitumen binder, overlaid with a traditional roadbase. The binder will, over a period of time, immerse through the old gravel road and the roadbase, creating a road surface resistant to moisture and significantly reducing dust.
An Otta Seal does not add to the structural strength of the road pavement by any significant amount, however, with well-maintained drainage the newly sealed pavement should provide a dust suppressing surface for a serviceable life of up fifteen years before a new reseal is needed.
Council’s Deputy General Manager Matt Fanning said he is particularly pleased with the use of the Otta Seal, as the binder uses ‘crumb rubber’ providing environmental incentives by recycling old car and truck tyres. Council engaged a contractor to undertaken the treatment between 11 and 12 December, 2018 after Council’s Operations staff had performed all pre-seal preparation.
The seal will be tested in 2019 to determine its effectiveness.If it is deemed a success Council can further develop this innovative approach by reducing the cost of the treatment.
It is estimated that the overall cost of treating and preparing the road site, in addition to the cost of the seal is approximately $72,000 for the 600 metre length of roadway, noting that the current cost of a full sealed road construction is approximately $500,000 to $600,000 per kilometre).
Further development of the trial will look to make use of more of the gravel that sits in the roadway, and rely less on expensive imported road base.
For further information regarding this new Dust Suppression Treatment please contact Matt Fanning, Deputy General Manager Operations on 6655 7300.