Weather smashes Nanaimo’s October rainfall records

NANAIMO - Deluge from autumn skies crush prior precipitation records.

Those who thought October was wetter than normal are right in their thinking.

According to Environment Canada, October was Nanaimo’s soggiest on record with 315.6 millimetres of rain, more than triple the normal precipitation of 102.2 mm.

“That’s 309 per cent of normal. … The last record was in 1975 for October at 289.1 millimetres,” said Armel Castellan, Environment Canada meteorologist.

Castellan said Nanaimo residents won’t be getting a break from rain until around Wednesday (Nov. 9) when the weather patterns will start to settle down.

Normal rainfall for November in Nanaimo is 197.2, but Bill Sims, city manager of water resources, noted Thursday the region has already received 55mm of rain in the city and 160mm of rain up at the city’s Jump Lake Watershed from a storm he described as more intense than the series of storms the Island braced for in mid October.

Early Thursday morning water overflowing the top of the South Fork Reservoir Dam was 1.55 metres deep.

The deluge also pushed water flow volumes in Nanaimo River Thursday morning to about 425 cubic metres per second, 10 times the 45 cubic metres per second normal flow volume for this time of year.

All that water rushing into the city’s reservoirs produced about 15 times the amount of allowable turbidity in Nanaimo’s water supply, which was cleaned up by the new South Fork Water Treatment Plant. It’s the second time this fall the plant has prevented a boil water advisory, Sims said.

“Within the month of October, and this was before yesterday’s storm, we had received something like 980mm of rain at the Jump Lake watershed,” Sims said. “In a month’s period that’s one of the highest we’ve ever seen.”

A normal monthly maximum for the wettest months of November, December and January, he said, is about 800mm of rain.

“And here we are, 1,000 in October. Crazy,” Sims said.

Castellan said meteorological predictions for the B.C. Coast after mid November point toward a seasonally “normal” winter with average rainfall and slightly colder than normal temperatures.