This is the post I've owed you since 2021. Every November when the first big rain event rolls in, my call volume doubles, and almost all of it is cables. Not springs. Cables. Here is why that happens, what the 2021 event specifically revealed, and what you can do about it before the next one.
What an atmospheric river actually is
An atmospheric river is a narrow, fast-moving band of water vapour in the lower atmosphere — picture a hose of moist Pacific air a few hundred kilometres wide pointed at the BC coast. When it hits the Coast Mountains, the air rises, cools, and dumps the moisture as rain. A strong one can drop more rain in 48 hours than parts of the Lower Mainland normally see in a month.
Most of us grew up calling this the Pineapple Express. Strictly speaking, that's one flavour of atmospheric river — the kind that draws its moisture from near Hawaii. These days forecasters and the news use the broader term, and I suspect a few anchors were relieved to stop saying the name of a Seth Rogen movie on serious broadcasts. Same weather. The rain doesn't care what we call it.
The November 2021 event, briefly
November 13–15, 2021. An atmospheric river stalled over southwestern BC for roughly two days, and parts of the Fraser Valley and the Hope area measured well over 200 mm of rain. Abbotsford got hit hardest — the Nooksack River spilled over the border onto the Sumas Prairie, and the Barrowtown pump station only kept running because volunteers sandbagged it overnight. The Coquihalla and the highways through the Fraser Canyon were washed out in multiple places. Damage ran into the billions provincewide.
From a garage door service standpoint, the event didn't damage any doors directly. What it did was concentrate three months of cable corrosion into a single weekend, and then I spent November and December cleaning up the failures that followed.
Why cables fail before springs
I've said this before in the coastal corrosion post but it's worth saying again here, because it's the central fact:
A garage door cable is galvanized steel wire rope about 1/8" thick, with roughly 50 fine strands twisted together. Per pound of metal, it has far more surface exposed to air than a spring does. More surface, more places to rust — and a thin strand only has to pit a little before it snaps.
Cables also live near the bottom of the door. The bottom of the door is the wettest part of the door. Rain blows in under the seal. Condensation forms on the floor. Snow drifts melt against the bottom panel. The cable terminates in a steel bracket at the bottom corner, and that bracket spends its life sitting in a small puddle of whatever the weather delivered.
By the time a spring gives up on one of these doors, there's often been a cable problem for months that nobody noticed.
The 2021 lesson — humidity isn't a coastal problem anymore
Before 2021, we treated humidity as a coastal-spec issue. Tsawwassen, oceanfront Steveston, the dyke in Ladner — those got stainless cables and the inland addresses didn't. After 2021, that's not how I think about it. The atmospheric river dumped Pacific moisture across the entire Lower Mainland for two days straight. Cables in Maple Ridge, Pitt Meadows, and Port Coquitlam started rusting on a coastal timeline because, for two days, they were soaked like coastal ones.
Climate projections point to stronger atmospheric rivers on this coast, and we've had several more big ones since 2021. The working assumption in our shop is that this is the new pattern, not an outlier. Plan your cables for that, not for what the climate was in 2015.
What you actually see when a cable fails
The first symptom — a noise.
A frayed cable rubbing its way around the drum makes a scraping, ticking or twanging sound that wasn't there last month. If you hear something new during a door cycle, that's where to look first.
The second symptom — one side hangs lower than the other.
If one cable stretches, slips on its drum, or partly fails, the door sits crooked when closed. Stand in front of the door and look at the bottom edge. Level? Good. Tilted? Cable.
The third symptom — the door slams down or won't close evenly.
One cable has let go entirely. The remaining cable is doing all the work and the door is wildly out of balance. Stop using the door. The next cycle could drop a 200-pound door.
What we do differently for each city
- North Vancouver and West Van — Highest rainfall in Metro Vancouver, 1,800 to 2,500 mm/year. Oil-tempered springs and oil-treated galvanized cables as a minimum, stainless cables on waterfront properties. Lynn Valley gets the rain. Deep Cove gets the rain plus the salt.
- Tsawwassen, White Rock, oceanfront Richmond — Salt is the dominant variable. Stainless cables, oil-tempered springs. Twice-yearly fresh-water rinse helps.
- Maple Ridge and Port Coquitlam — Used to be inland-spec territory. Post-2021, we run oil-treated galvanized cables here too. Atmospheric river country.
- Surrey, Langley, central Burnaby — Standard oil-tempered, galvanized cables. The 2021 event lasted long enough to affect everyone, but inland addresses still rust slower than coastal.
- Pitt Meadows specifically — Fraser-Pitt floodplain humidity is high year-round. Cables here fail before springs, almost every time, so the local tech carries extra cable stock.
What you can do between service calls
Look at the cables once a month, from a safe angle.
Open the door halfway and look at the bottom corner where the cable terminates. You're looking for visible rust, fraying, or any difference between the left and right cables. Don't touch. Don't reach in. Just look. If one cable looks different from the other, that's the call.
Don't let water pool at the bottom of the door.
If your garage floor slopes toward the door (most do), and the weather seal at the bottom is worn, water tracks in under the door and sits at the base — exactly where the cable lives. A $20 bottom seal replacement once every 5 years is the cheapest cable insurance there is.
Wipe the cable terminations dry after a major rain event.
I'm not asking you to do this every week. I'm saying after a big atmospheric-river day, take a dry towel to the cable end where it attaches at the bottom corner. Two minutes. Maybe twice a winter. Adds years.
The honest bit
The cable is the cheapest part of a spring job. It's also the part that fails first and the part most homeowners forget exists. The reason we include free cables with the two-spring tier isn't generosity — it's that we've learned the hard way that doing the springs without doing the cables means we'll be back in 18 months. The atmospheric river didn't change our spec — it just made the spec we were already running look smart in hindsight.
Call when you hear a new noise. Call after a big rain. Same family. Same number.