Drain unblocking

Drain unblocking is the process of removing fats, grease, silt, wet wipes, scale or other obstructions from a foul or surface water drain so that wastewater can flow freely again. Typical methods include rodding, plunging, electro-mechanical cable machines and high-pressure water jetting, chosen according to the diameter of the pipe and the nature of the blockage. Engineers usually carry out a CCTV survey afterwards to confirm the line is clear and to identify any defects that contributed to the problem. The work is routine for qualified drainage engineers and is normally completed in one visit lasting one to three hours. Recurring blockages in a Camden or Islington terrace often point to displaced clay joints or root ingress, in which case lining or excavation may be needed.