Does anyone know what the vertical pipe is for in this image? NMP but I think is the set up we have under our garden. Stuck a tape measure down the pipe and it is 1.8m deep and dry. Odd because i've spent most of the afternoon jetwashing the drive and trying to clear a blockage from the Aco infront of the garage. If the Aco leads to this i would have expected a load of water to be in the crates.