A Tembusu tree that fell on a woman at the Singapore Botanic Gardens last year, killing her, was uprooted due to a combination of factors including heavy rainfall, strong winds and root problems, said Coroner Marvin Bay yesterday.
The coroner, who found Indian national Radhika Angara's death to be a tragic misadventure, added: "The wind had initiated the process by buffeting the 40m tall tree, causing considerable swaying. The swaying had transferred these strong imposed forces down the trunk and in turn caused the degraded tension roots to fracture."
He suggested that in the future, it would be useful for photographs to be taken during all inspections of significant trees, such as old and large ones. This, after he noted that there was an absence of verified and curated images of the Tembusu tree before it fell.
Coroner Bay added: "These recorded images would be useful in investigations and inquiries as an archive of contemporaneously taken photographs of the same tree can allow a more cogent analysis of the actual baseline health of the tree."
Madam Angara, 38, was attending an outdoor concert near the Shaw Foundation Symphony Stage at around 4.30pm on Feb 11 last year when the 40m-tall heritage tree came crashing down. She was taken to the National University Hospital and was pronounced dead about 45 minutes later.
Three experts gave their reports during an inquiry into her death. One of them, arborist Rick Thomas, said the tree could be about 270 years old. Coroner Bay said the reports all separately attributed the final failure of the tension roots to a combination of heavy rainfall and strong winds.
He also noted that the tree had a severe decay of the roots below soil level and that this decay had eventually migrated to the trunk itself, to cause a massive internal cavity.
This cavity would have been uncovered had there been an invasive second-level advanced inspection with diagnostic equipment. The tools used would have detected the presence of decay and provided advance warning that the tree might be potentially unsafe.
The coroner noted Minister for National Development Lawrence Wong had told Parliament on April 3 last year that an enhanced inspection regime for old and large trees had been in place since November 2016.
Coroner Bay said: "The detailed second-level inspections would be conducted yearly with diagnostic equipment, also with a boosted cadre of qualified arborists."
However, the tree was last inspected on Sept 29, 2016, which would have been before the new regime began.
Madam Angara's family members were in court yesterday and when approached, her sister told reporters: "These people had the tools and the wherewithal to prevent this mishap. We believe it was their inaction that caused us to lose my sister...
"Our family has lost a sister, a wife, a daughter and a mother in a truly horrific manner."