Mystery Hole Appeared in Front garden after Laying new Soil Drainage pipes, concrete, footings and foundations. Post your questions and find answers here

[BML18]

I am not sure if I am posting in the right forum but I have returned home to find this hole appeared in the front garden - we laid new soil this weekend and this clay/sand like bubble/hole has erupted up. Could it be a leak or something else? Does it look serious? Thank you in advance for any thoughts.

[diggerjones]

Did you lay soil over abit of building sand.?