Foul water flooding a garden is a serious incident in which sewage rises from a blocked or surcharged drain, gully or manhole and pools on the ground. The contents may include human waste, paper and wet wipes, posing a hazard to people, pets and surrounding planting. Causes include downstream blockages in the lateral drain, surcharging combined sewers during heavy rainfall and structural collapse of the underground pipe. In London boroughs served by combined sewers, intense storms can also surcharge Thames Water mains and force foul flows back through inspection chambers. Engineers usually address common causes urgently by clearing the line through the nearest access point and disinfecting affected surfaces in accordance with industry practice. A CCTV survey afterwards typically identifies any underlying defect, with repair carried out under BS EN 752 principles.
Foul water flooding garden
Sewage rising onto garden ground from a blocked drain, gully or manhole.
