As mentioned elsewhere, the roadway has not been constructed to highway standard. The base layer is compacted chalk and the wearing surface is an accumulation of tar and chippings applied over the years.
Up until the mid 90s, the surface was treated with a top dressing of tar & chippings every 5 years or so. After this time the SHA employed a professional highways engineer to advise us on what, if any, remedial work needed to be carried out. Our advise was that top dressing was not necessary as this did not increase the strength of the road – a better plan would be to patch the road when problems appeared. This strategy has been followed ever since, and appears to be satisfactory. At present (2025) we have had the road professionally surveyed about every 3 years and carried out repairs as indicated.