By Lehlohonolo Lehana.
Transport minister Fikile Mbalula says that the government will on Monday (8 August) roll out a programme to address potholes across all national provinces called Vala Zonke.
It comes as the country is facing a huge road infrastructure maintenance backlog estimated to be more than R200 billion. At the same time, 40% of the provincial network has reached the end of its design life, and approximately 80% of the national road network is now older than its 20-year design life, the minister has said.
To compound matters, he said that issues such as a shortage of skills and lack of funding continue to hinder the sector.
The Department of Transport is supporting District Municipalities with ‘Road Infrastructure Planning’ through the Rural Road Asset Management Systems Grant (RRAMSG), as provided for in the Division of Revenue Act (DORA).
“The National Department of Transport has been hard at work intensifying interventions aimed at addressing challenges relating to road infrastructure with a comprehensive plan to address potholes across all spheres of government, with the South African National Roads Agency (SANRAL) leading the labour-intensive national project,” said the minister.
“The rollout of this programme will be the implementation of an integrated, rigorous and comprehensive plan that will drive interventions to ensure that the department improves the overall condition index of roads at local and provincial authorities.”
Provincial authorities have previously detailed strategies to address potholes outlining:
°The magnitude of potholes in their area of responsibility;
°Existing strategies they are using to fix them;
°Turnaround time to fix potholes;
Vehicles of all descriptions – including trucks and trailers – are suffering damage due to the shocking condition of the roads in the country.
The government has said that it will target physical works including resealing, blacktop patching, pothole repairs and maintenance of gravel roads.
Among projects authorities have committed to is the maintenance of about 20,000km of roads in South Africa’s secondary road network by March next year. These are provincial roads in urgent need of being upgraded to an acceptable state of repair.
Mbalula said there are numerous factors influencing the performance of pavement and the development of potholes, with the following five considered the most influential:
°Traffic is the most important factor influencing pavement performance. The performance of pavements is mostly influenced by the loading magnitude, configuration and the number of load repetitions by heavy vehicles.
°Moisture can significantly weaken the support strength of natural gravel materials, especially the subgrade.
°The subgrade is the underlying soil that supports the applied wheel loads. If the subgrade is too weak to support the wheel loads, the pavement will flex excessively which ultimately causes the pavement to fail.
°Failure to obtain proper compaction, improper moisture conditions during construction, quality of materials, and accurate layer thickness (after compaction) all directly affect the performance of a pavement.
Pavement performance depends on what, when, and how maintenance is performed. No matter how well the pavement is built, it will deteriorate over time based upon the above-mentioned factors.