120 mm of rain in 24 hours, 60 of it in one hour.
There was a fair bit of damage to public infrastructure. The Wellington water main was undercut in a few places, power poles were washed out and fell over, requiring replacement and relocation.
Although this was a pretty epic flood, the culverts and bridges over Takapu Stream are undersized and flooding events on the road are not uncommon. If NZTA’s roading plans go ahead, the entire eastern flank of the valley — that’s the Belmont side, where nearly all of the streams tributaries come in — will have to be de-watered to protect and stabilise the new highway. That increased flow directly into Takapu Stream, plus the run-off from the highway itself, will mean flooding events like this one or worse will become much more commonplace.