drainage problem

i have a recurring problem with my drainage system. After heavy rainfall the street drain level appears to get high, covering the outlet from my house drainage system through the garden. This appears to back the whole system towards the house causing overflows in the drains. Because of this I can usually tell a few days in advance when my drain is going to get blocked, and we get smells back into the house. Despite almost monthly Scottish Water visits over the winter, they do not seem to believe that the problem lies in the street drain. On previous occasions the water technicians tell me there is baby wipes etc blocking the drain, yet we do not use such items, and most certainly would not put them down the toilet if I did. Would appreciate your advice in the matter.

At first glance there seems to be some dereliction of duty on the part of the drainage authority.

I don't know how the regulations work in Scotland, but have you tried getting guidance from your local environmental health department?

Or the Citizens' Advice Bureau?