Online Reporter
Nyore Madzianike
Senior Reporter
Newly-constructed major roads, particularly highways, are designed to last at least 20 years, with routine maintenance expected to begin after a minimum of five years, Ministry of Transport and Infrastructural Development chief director of roads Engineer David Jana has said.
He was presenting oral evidence on issues raised in the third and fourth quarter budget reports before the Parliamentary Portfolio Committee on Transport and Infrastructural Development at the new Parliament Building in Mt Hampden.
Eng Jana said within the 20-year design lifespan, routine maintenance activities such as grass cutting and drain clearing are carried out annually to preserve road conditions and reduce early deterioration.
The committee had raised concerns over alleged poor workmanship by some contractors engaged in major road construction projects.
Eng Jana said drainage remained the biggest challenge affecting road durability.
“So, you will appreciate that having had a deficit in terms of activities of roads for 20 years, we have mainly been focusing on the carriageway and less effort has been on drainage, which we are now working on.
“When you deal with drainage, you deal with the entire area, not just where the road is. So, most of the potholes that you find have been caused by water, which is stagnant, which is then making the bases to fail.
“Drainage has given us premature failures in urban areas and that is something that we are looking at now to clear drains,” he said.
He further attributed some road failures to siltation in rivers, which reduces the capacity of water channels to effectively drain storm water from urban centres.
Eng Jana also said overloading by heavy trucks continued to put excessive pressure on road infrastructure, accelerating deterioration in some sections.
