Highways contractor Kier has apologised after works it carried out to resurface carriageways in Lincolnshire failed.
Kier started works to surface dress roads in the Barrowby Gate area of Grantham, Lincolnshire in September last year. However the repairs have caused complaints from motorists about excess chippings left on the roads.
The company has confirmed that they will repeat the works later this year at no cost to the taxpayer.
Surface dressing is a cheaper alternative to resurfacing roads, and normally extends the life of a roadway without the need to completely strip and resurface the road.
The process consists of spraying a bitumen binder onto the road surface, and then pressing stone chippings into the binder with a roller. Excess chippings are used to ensure a full coverage, and the excess is swept away.
The bitumen binder is effective at sealing existing cracks in the road surface and is resistant to the effects of oxidising UV radiation from the sun. The main drawback of this method is that it does not regulate uneven surfaces or correct structural defects in the road.
The dressing normally lasts 10 years before needing to be repeated or completely resurfaced.
However, in the case of Grantham loose chippings have caused issues to motorists in the area according to Lincolnshire County Council, and Kier is working to assess the extent of the damage and is removing excess chippings manually.
In a letter to affected residents, a spokesperson for Kier said: “Engineers have visited the site and identified roads that are showing signs of failure and regrettably chippings may continue to strip from the surface.
“Unfortunately, remedial works (which will be carried out at the contractor’s expense) cannot take place until the full extent of the failure is known.
“Due to the nature of these works, which are seasonal, these will not be able to be carried out until the spring of 2019.”
The letter adds: “However, please be assured that we will continue to monitor all the sites and sweeping will take place on a weekly basis where required. You may have noticed that we have already erected loose chipping signs to warn motorists.
“It is regrettable that the site has started to fail, but it’s also worth noting that we have successfully surface dressed in excess of three million square metres this year alone, and over the course of the past eight years this process has achieved a 98.7% success rate and is a vital tool in the county council’s asset management strategy.
“Once again please accept our sincere apologies for any inconvenience this has caused.”
Kier is unable to carry out the replacement works sooner because the process of surface dressing is dependent on season, usually carried out between April and September as warm and dry weather is needed to ensure the dressing becomes established.
Kier has also recently unveiled an innovation for surface redressing that should make the follow up repairs in Grantham much faster. The new system replaces individual truckloads of chippings with “a conveyor system to dispense aggregate into the Chipping machine; meaning that stopping to reload the chipping machine from a tipping truck is no longer needed”.
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