What causes potholes – and who gets hurt when they appear

The photo published in the print edition with your article shows clearly what I see in my town: that the potholes are at the edge of a trench dug for gas, electricity, sewers or water (‘A national disgrace’: cyclists and motorists lament UK’s pothole-ridden roads, 22 August).
In the inner city here the roads were made long ago to high standards, with macadam base (graded layers of stone) topped with setts (cubes of granite). These still underlie the tarmac surface, but when dug out they are not replaced but tipped back in and surfaced with asphalt – which is good until it begins to fray at the edges. If the services were made to re-lay the road to the original standard, would this prevent the damage?June PerryNottingham
Sadly, it’s not only cyclists and motorists who are affected by potholes. Crossing Lymington High Street in April, my wife caught her foot in a long pothole in the road. She fell and broke her arm at the shoulder, causing immense pain. Four months later, she is still in some difficulty, and realises that full and complete recovery is not going to happen.
I contacted both Lymington and Pennington town council and Hampshire county council about my wife’s accident, but I’ve heard back from neither council.Roly LovellShepherdswell, Kent