Risk register · entry
Q2 · The CoconutChamplain Towers collapse
The concrete corrosion was documented years earlier, never repaired, and the tower pancaked overnight.
The rare, high-impact event that was always coming, and was always going to be called unforeseeable afterwards.
Why this room
The physical mechanism was simple and legible, not a complex or opaque system, since a single engineer's report could name the exact defect and price the fix, but the payoff structure was a classic fat tail: near-zero visible probability for years while corrosion crept along, then a discrete, catastrophic, all-or-nothing collapse, the coconut that hangs in plain sight until gravity settles the argument.
The record
- 98 confirmed deathscertain
- 11 injuredlikely
- 136 units in the buildingcertain
- Building completed 1981certain
- Collapse at approximately 1:22 a.m. on June 24, 2021certain
- Morabito Consultants report dated October 8, 2018 warning of major structural damagecertain
- $15 million estimated remedial repair programcertain
- Repair program approved April 9, 2021certain
- NIST: punching shear failure at two garage column-to-pool deck slab connections began in early June 2021, about three weeks before the collapsecertain
- Some slab-column connections had less than half the code-required flexural/punching-shear strengthlikely
- $1.02 billion victims' and owners' settlement approved June 23, 2022certain
- Remaining structure demolished July 4, 2021certain
- Site sold for $120 million in May 2022 to Damaccertain
- Building subsided roughly 2mm per year during the 1990s per a separate ground-deformation studyuncertain
- NIST released final technical findings in June 2026, nearly five years after the collapsecertain
Sources
The book
This entry is one of 111 in the register. The full story, and what it cost the people who lived it, is in Risky Business by Claudia Zeisberger, David Munro and Joanna Reijgersberg-Siew.
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