Longmont · Boulder County
24 Hour Emergency Plumber in Longmont, CO
Longmont's Old Town and central neighborhoods have early-1900s and mid-century homes with galvanized pipe, cast iron drains and clay sewer laterals under mature trees, so root-blocked sewers and pipe failures are common emergencies.
First: If water is moving, close the main shutoff; if sewage is coming up a drain, stop using water everywhere instead.
By calling, you agree your call may be recorded and connected to an independent, licensed plumbing contractor in your area, who may call or text you back about your request. Free referral service; consent is not a condition of purchase. Privacy policy.
Longmont emergency plumbing: call now
(833) 615-1180Do this first
If water is moving, close the main shutoff; if sewage is coming up a drain, stop using water everywhere instead.
Call right away if: a frozen pipe that has split or is dripping as it thaws; water coming through a basement ceiling or wall; sewage backing up through a basement floor drain.
Pick what's happening in your Longmont home
Pipe frozen, not leaking yet
Do now
- Find and test the main shutoff before the pipe thaws.
- Crack open the faucet on that line so thawing water can flow out.
- Warm the section with a hair dryer or a space heater kept at a safe distance.
Avoid
- No torches or lighters on a frozen pipe; they start fires inside walls.
- Don't leave a heater running unattended in a crawl space or garage.
Call: If you can't reach the frozen section, or several fixtures have no water.
Full step-by-step guideBurst pipe or leak you can't stop
Do now
- Close the main shutoff; in a basement home it's usually where the line enters through the foundation.
- Cut the breaker to any circuit with water near it.
- Open a basement laundry tub or the lowest faucet to drain the lines.
Avoid
- Stay out of standing water until the power to that area is off.
- Don't turn the water back on to test the repair yourself.
Call: Now, while the main is closed: the fix is faster before drywall and carpet soak through.
Full step-by-step guideSewage in the basement
Do now
- Tell everyone in the house: no showers, laundry, dishwasher or flushing until the line is clear.
- Keep kids and pets out of the basement.
- Note where the sewer cleanout is for the plumber.
Avoid
- Skip the chemical drain opener: it won't clear a main-line block and it burns whoever snakes the line next.
- Every flush upstairs adds more water to the basement.
Call: Right away: sewage at a floor drain means the main line is blocked.
Full step-by-step guideWater heater leaking
Do now
- Set the gas valve to off (most homes here have gas heaters) or switch off the breaker.
- Close the cold-water valve on top of the tank.
- Move stored items away.
Avoid
- If you smell gas, leave the house and call the gas utility first.
- Don't open the drain or relief valve while the water is hot.
Call: When the tank itself is leaking or the relief valve keeps discharging.
Coming home to a leak after being away
Do now
- Close the main shutoff before walking through the house.
- Turn off power to any room with water near outlets.
- Photograph everything before moving anything.
Avoid
- Don't turn the water back on until the source is found and repaired.
Call: Right away: leaks in an empty house have usually spread further than they look.
Full step-by-step guideLocal conditions
Emergency Plumbing in Longmont: what's different here
Longmont's Old Town and central neighborhoods have early-1900s and mid-century homes with galvanized pipe, cast iron drains and clay sewer laterals under mature trees, so root-blocked sewers and pipe failures are common emergencies. Areas near the St. Vrain can see sewer stress during high water, and some homes were repaired after the 2013 flood.
Outer neighborhoods from the 1980s onward see water heater and supply-line failures in finished basements.
In older Longmont homes the main shutoff is usually in the basement near the front foundation wall; in newer homes it's in the mechanical room.
If it happens in Longmont: the likely cause and the first move
- 1. Local condition
Longmont has a broad housing mix, with many mid-century homes.
- 2. Risk to the home
Older main valves may not close fully.
- 3. What goes wrong
A leak you can't stop at the house.
- 4. What to do
Test your main valve now; the utility can shut off at the meter.
Emergency Plumbing: the full guide
More on emergency plumbing: signs, steps and costs.
Emergency Plumbing questions from Longmont homeowners
Who fixes a sewer backup in Longmont?
A plumber clears your lateral; the city handles problems in the public main.
Should I install a backwater valve?
In low areas near the river, it can keep sewage out of basement drains.
Service area
Emergency Plumbing near Longmont
- Emergency Plumbing in Fort Collins
- Emergency Plumbing in Loveland
- Emergency Plumbing in Greeley
- Emergency Plumbing in Windsor
- Emergency Plumbing in Timnath
- Emergency Plumbing in Berthoud
- Emergency Plumbing in Johnstown
- Emergency Plumbing in Milliken
- Emergency Plumbing in Evans
- Emergency Plumbing in Firestone
- Emergency Plumbing in Frederick
- Emergency Plumbing in Dacono
- Emergency Plumbing in Fort Lupton
- Emergency Plumbing in Mead
- Emergency Plumbing in Platteville
- Emergency Plumbing in Erie
- Emergency Plumbing in Wellington
- Emergency Plumbing in Severance
- Emergency Plumbing in Eaton
- Emergency Plumbing in Estes Park
- Emergency Plumbing in LaSalle
- Emergency Plumbing in Kersey
Related
Other Longmont services

Burst & Frozen Pipe Repair
Frozen pipe repair thaws the frozen section safely and checks it for splits; burst pipe repair replaces the split section and fixes whatever let it freeze.
Learn more
Emergency Leak Repair
Emergency leak repair stops water that's actively escaping, from a failed supply line, a cracked fitting, a leaking valve or a split pipe, and makes a permanent repair so water can be turned back on.
Learn more
Basement Sewer Backup
A basement sewer backup happens when the main sewer line is blocked or the city main surcharges, so waste comes up the lowest drain, usually the basement floor drain.
Learn more
Need emergency plumbing in Longmont?
Cold snaps, failed supply lines, sewer blockages and aging water heaters.
