Overview
The approximately 36,000 gullies in Bonn are cleaned using five so-called sludge suction vehicles.
Surface water with dirt, autumn leaves and gritting material (winter) runs into the gullies. The "flushing material" collected in the gully is regularly sucked up by the sludge suction truck and disposed of. The gullies are cleaned on average twice a year, more often if necessary.
Sink boxes that are parked up are repeatedly approached to ensure that they are also cleaned as regularly as possible, on average twice a year.