The deep pit, which measured 4.5 meters, appeared beneath pavers just 1.5 meters away from the house in August 2022.
The homeowner contacted QBE insurance to lodge a claim, prompting the insurer to send a team to cordon off the affected area for safety.
The homeowner argued that the pit had been formed by a leaking pipe and believed the visible water flow at the bottom was evidence of such. He suggested that the water leak had caused soil erosion, exacerbating the formation of the pit.
In response, QBE appointed a forensic structural engineer to investigate. The engineer, assisted by a plumber, conducted several tests and authored three reports on their findings.
The investigation concluded that the pit resulted from the collapse of a well capping that had been in place for over five decades, predating the home's construction according to the neighborhood residents' accounts.
According to the engineer, the old well capping had eroded over time, explaining the presence of water at the base. Nearby sewer and stormwater pipes were examined, and it was found that water flow into the pit had been consistent. A sewer pipe leakage, identified approximately 19 meters from the pit, was determined to be too far away to contribute to its formation.
No legal or physical connection was determined to link the sewer leakage or any nearby pipes to the well's deterioration. The plumber validated the engineer's conclusions, confirming a lack of nearby pipe networks capable of forming a sinkhole.
The Australian Financial Complaints Authority (AFCA) later ruled in favor of QBE, citing comprehensive evidence provided by the engineer. The findings firmly established that the pit was a disused well, lacking any evident links to a leaking sewer or other leaks.
AFCA endorsed, "The expert evidence substantiates that the pit originates from a long-decommissioned well existing before the complainant’s house was built. Despite extensive testing, the results indicate no connection between any pipe leaks and the pit’s formation, the water at its base, or the erosion observed."
Though QBE did agree to compensate for incidental damages done during the examination process, including $1122 for the damage to the homeowner’s timber deck and an additional $1500 for the delays in processing the claim, which took over six months.
This case, initially reported by insurancenews.com.au, underscores the critical role of thorough expert investigation to differentiate between naturally occurring subsidence and structural failures caused by other factors.
