There was a problem in Liphook with surface dressing but I thought it may be useful for a wider number of people to be aware of how this operates throughout the County.

Surface dressing is programmed for the same time each year as this is the best time for the chippings to embed into the bitumen in the road. As you will remember, this April turned particularly cold for a number of weeks, and the unexpected cold weather caused the bitumen to harden, resulting in the stone chippings failing to embed fully into the bitumen layer when mechanically rolled .
Because the chippings did not embed sufficiently, subsequent traffic on the road caused the loss of chippings by plucking them out of the surface. Unfortunately, this was exacerbated by many vehicles failing to observe the reduced speed limit signs which are installed temporarily after surface dressing is completed. The stone chipping loss exposed bitumen at the road surface and our contractor (RMS) carried out early remedial work to try and correct the problem. This involved laying down another layer of bitumen and another layer of stone chippings.
The sudden hot spell of weather following almost immediately after the remedial work has caused the bitumen to soften enough for the stone chippings to become fully embedded in the bitumen layers, with the result that a tacky surface forms in the wheel tracks on the road surface.
The standard method of dealing with this is to place a 3mm or lower size stone over the tacky surface, and this was what was done in Liphook. This usually resolves the problem, but the problem was more severe because of the amount of bitumen present on the road, so the level of ‘dusting’ is more than normal. The concern raised by local residents was the level of dust raised when traffic ran over the road surface and the amount of loose grit on the road.
Safety is the critical concern which is why we have left the signs in place with warning of loose stones and advising a speed limit of 10mph. We are currently visiting the site daily to sweep the road and to monitor the condition. The use of water dampening is being explored in association with the sweeping operations to minimise dust levels. Daytime temperatures are currently forecast to be lowering and whilst the potential for continuing problems exists the likelihood is reduced. However a long term solution needs to be implemented, so an urgent meeting with the contractor and suppliers is being held as a matter of priority to determine what longer term remedial works are necessary at each of the 6 sites.
This year to date we have completed surface dressing on just over 1,000,000 square metres of road ( approx 104 miles of road length) in Hampshire on over 240 different sites. Significant failures of the surface dressing is restricted to just 6 sites which will require further remedial action of some kind, ranging from dusting to water retexturing and possibly some areas of resurfacing. All this defective work will be paid for by the contractor, at their expense and not at the expense of the council tax payer, in line with the terms by which the work was commissioned. The County has a specification contract and the contractor has to guarantee the site for 2 years.
I would like to apologise for the inconvenience to residents.
Finally for your information please find below questions and responses raised by the press in relation to the surface dressing problem.

• What road temperature are roads likely to start melting? The bitumen used in surface dressing usually withstand temps up to 40 degrees. Although air temperatures have been in the high 20 degrees recent road surface temperatures have been over 40 degrees and these were forecast over the last weekend when the failures became more prevalent.

• What is the advice for motorists if when driving they encounter a road surface that is melting? Should drivers encounter sites with binder on the surface, they should observe and drive at the recommended 10mph speed limit and if possible avoid the site and take an alternative route. The 10mph recommended speed limit is for driving through any newly surface dressed road site due to loose chippings being present on the road surface. Any site that motorists come across where bitumen is on the surface should be reported the Council on Hantsdirect 0845 603 5633

• How many roads did we have to treat in anyway over the weekend? – Over the weekend we treated 6 sections of road at the following locations, A339 Basingstoke rd Alton, B3004 Cakers Lane Alton, Oakhanger Road Bordon, A325 Petersfield Rd Bordon, Portsmouth and London Road Liphook.

• What were the measures taken? Contractor dusted sites with a 3mm and less size crushed stone to absorb tacky bitumen and then sweep loose material, Cakers Lane was also redressed with additional 6mm chippings. Additional signing indicating slippery/uneven roads were also deployed to site. The sites are being checked daily in the hot weather.

• If we sent gritting lorries out to disperse crushed rock – how many? Over the weekend we used 3 dedicated dusting lorries. We also had 3 sweepers following up as necessary. Dusting of these sites has been carried out every day since Wednesday 23 afternoon.

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