Why is winter hard on Flagstaff drains?
Flagstaff sits at about 7,000 feet, so winter nights often drop well below freezing. Cold slows water and grease in pipes, exposed drain lines can freeze, and snow can block plumbing vents. Add holiday cooking and houseguests, and drains carry more load just when they are most at risk.
Most winter drain problems are easy to prevent with a little planning. The tips below are simple things you can do yourself, plus clear signs that it is time to call a pro.
Can drain and sewer lines freeze in Flagstaff?
Yes. Drain lines that run through crawl spaces, garages, exterior walls or shallow ground can freeze during a hard cold snap, especially when water sits in them. A frozen drain acts like a clog: water backs up because it has nowhere to go. Buried main lines are less likely to freeze but can when they are shallow.
Signs of a frozen drain line include:
- A drain that worked yesterday stops draining on a very cold morning
- Gurgling from a fixture on an outside wall
- Water backing up in a laundry or utility sink in the garage
- Slow drains in a home that sat empty and cold
Never use an open flame or a torch on pipes. Warm the space instead, and call if the drain does not clear. A drain that was frozen can also hide a real clog, since grease and debris harden in the cold.
What should I do to get my drains ready for winter?
Before the first hard freeze, find your outside sewer cleanout, insulate drain pipes in cold spaces, disconnect garden hoses, and fix slow drains while the weather is mild. If you have had root or grease clogs, fall is the best time for a main line cleaning, before snow covers the cleanout.
- Find and mark your cleanout. It is usually a capped pipe near the house. Mark it with a tall stake so you can find it under snow.
- Insulate exposed drain pipes. Wrap pipes in crawl spaces, garages and under-sink cabinets on outside walls.
- Seal cold air leaks. Close crawl space vents and gaps where cold air reaches pipes.
- Fix slow drains now. A slow drain in October is a full clog in January. See our drain cleaning services.
- Clean the main line if it has a history. Roots and grease are easier to clear before the ground freezes and snow piles up. Our guide to tree roots in sewer lines explains why.
How do I avoid kitchen drain clogs during the holidays?
Never pour grease, fat or oil down the sink. Let it cool, then put it in the trash. Scrape plates into the trash, go easy on the garbage disposal, and run hot water after use. Cold pipes make grease harden faster, so winter holiday cooking is a top cause of kitchen clogs.
- Pour cooled grease into a can or jar and throw it away
- Keep potato peels, rice, pasta and coffee grounds out of the disposal
- Run laundry and the dishwasher at different times when guests are over
- Put a trash can in guest bathrooms so wipes do not get flushed
If your kitchen line clogs every winter, grease is likely coating the pipe. Hydro jetting removes that buildup instead of just poking a hole in it.
What should I do if my sewer backs up in winter?
Stop using water right away. Do not flush, run the washer or use the dishwasher. Keep chemical drain cleaners out of the pipes, move valuables away from the drain, keep kids and pets away from sewage, and call for help. If you can find the outside cleanout cap, it helps the technician get started fast.
Our homepage has a full step-by-step sewer backup checklist. A backup is a health risk, so do not wait for it to clear on its own.
Can snow on the roof affect my drains?
It can. Every drain system has vent pipes that poke through the roof and let air in so water flows smoothly. When deep snow or ice blocks a vent, drains can turn slow and gurgle, and you may smell sewer gas indoors. Clearing the vent usually fixes it.
Only clear a roof vent if you can do it safely from the ground. Climbing an icy roof is dangerous. If gurgling and odors continue after the snow melts, the vent or drain may have a separate clog.
How do I protect drains in a cabin or second home?
Keep the heat on at a safe low setting, shut off the main water if you will be gone for a long time, and have someone check the home after cold snaps. Water left sitting in traps and drain lines in an unheated home can freeze. Plan your winterizing before the first hard freeze.
If you own a rental near Northern Arizona University or a cabin you visit on weekends, a quick check after the first big storm can save you from a surprise backup. We serve all of Flagstaff, from Fort Valley to Continental Country Club and beyond.
Frequently asked questions
Should I let my faucets drip in a Flagstaff freeze?
A slow drip can help keep water supply pipes on outside walls from freezing during a hard cold snap. Make sure the drain is clear first, so the dripping water has somewhere to go.
Can I pour hot water down a frozen drain?
Warm, not boiling, water may help a lightly frozen sink drain. Do not use boiling water on PVC pipe or toilets, and never use a torch. If the drain does not clear, call a pro.
Do you come out during snowstorms?
Yes. We work 24/7 in all weather across Flagstaff, including nights, weekends and holidays.
When is the best time for a main sewer line cleaning?
Early fall is ideal, before the ground freezes and snow covers your cleanout. If you have a root or grease problem, cleaning before winter lowers the chance of a holiday backup.
