Farmington can go weeks without a drop of rain, the desert hardpan baking solid under a July sun, and then a monsoon storm rolls in from the south and drops an inch of water in forty minutes. That contrast is exactly why the drain and sewer problems we see every summer aren’t just inconvenient. They’re predictable, and they’re preventable. We’ve been serving Farmington families since 1988, and every monsoon season confirms the same pattern: homeowners who prepared ahead stay dry, and homeowners who assumed rain was an outdoor problem end up with sewage at their floor drain.
Why Monsoon Rain Hits Farmington’s Drains Differently
Farmington averages around eight inches of rain per year, based on NMSU Agricultural Science Center records going back to 1969. That’s not much. But the distribution is what makes it dangerous for your plumbing: the majority of that annual total arrives in intense bursts during monsoon season, not in the slow, steady rainfall that ground can gradually absorb.
The deeper problem is the soil itself. Caliche, a dense calcium carbonate-rich hardpan layer that underlies much of the Farmington area, doesn’t absorb water the way sandy or loam soils do. It sheds it. When the North American Monsoon System pushes moisture up from the Gulf of California and drops it fast on ground that’s been bone-dry for months, that water has almost nowhere to go. It moves laterally across the surface, toward foundations, toward drain grates, and into any opening in your sewer cleanout system it can find.
What a Heavy Storm Does to Your Sewer System
Most homeowners picture their drains as a one-way system. Water goes in, wastewater goes out. During a heavy monsoon, that assumption breaks down. When stormwater infiltration and inflow (groundwater and surface runoff entering the sewer network through cracks, joints, and open connections) overwhelms the municipal system, pressure builds in the mains. That pressure doesn’t disappear. It finds the path of least resistance, which is often back up through the sewer lateral into the lowest point in your home.
There’s an important responsibility line most Farmington homeowners don’t know about. The city maintains the main sewer interceptors and lift stations. The lateral line running from your house to the street connection is your responsibility, legally and financially. If that line cracks, sags, or backs up, the repair falls to you, not the city. That distinction matters enormously once a storm has already started.
Stormwater also carries sediment. Mud, sand, and fine debris enter the system through cracked cleanout caps or open drain grates during heavy runoff and can pack tight inside residential lines. A line that was borderline slow before the season can become fully blocked mid-storm.
Which Farmington Homes Face the Most Risk
Not every home faces equal risk. Older Farmington neighborhoods, including the Cultural District, are more likely to have original clay or cast-iron sewer laterals installed decades ago. Those materials crack, sag, and develop low spots called bellied sections where debris collects. Under normal dry conditions they may function adequately, but under monsoon saturation (when caliche soil shifts more than sandy soils would under the same water load) a lateral already stressed by age faces dramatically greater pressure.
Root intrusion compounds the risk. Tree roots that have been slowly widening small cracks in a lateral during dry months don’t stay stable when the soil saturates. Root systems swell around entry points when moisture becomes abundant, and a crack that let water trickle out for a year can become a blockage in the span of a single storm. Hydrostatic pressure (the force that saturated soil exerts against buried pipes from the outside) accelerates all of this by pushing against already-weakened sections of line.
Warning Signs Your System Is Already Under Stress
Certain behaviors point to a main sewer line problem rather than an isolated clog. Watch for these:
- Multiple drains gurgling or draining slowly at the same time after rain, particularly on the ground floor or in the basement
- Sewage odor inside the home following a storm, even without visible backup
- Water backing up into a floor drain or the lowest fixture in the house, which is where a reversing sewer lateral shows up first
- One fixture backing up when a different fixture is used (such as a toilet bubbling when you run the washing machine) which points to a main line problem rather than an isolated clog
- Water pooling in the yard above the path of your sewer lateral after a storm without any other obvious source, which can mean a cracked or separated pipe below grade
Any of these behaviors during or after a monsoon storm warrants a professional sewer inspection, not a store-bought drain treatment. A video camera inspection is the only way to confirm what’s actually happening inside the line.
What to Do Before the Season & During a Storm
The actions that matter most before monsoon season and the steps you can take during an active storm are meaningfully different, so it’s worth separating them.
Before Monsoon Season
If your home is more than 20 years old or you have mature trees near the sewer line, schedule a video camera inspection before July. A camera run through the lateral reveals root intrusion, bellied sections, cracked pipe, and buildup that slow-drain symptoms alone can’t locate. Hydro-jetting (which uses high-pressure water to clear the line completely) is far more effective than auger snaking for removing compacted debris and root material before it becomes a wet-season blockage.
Check your sewer cleanout cap: it should be tight, undamaged, and seated properly. A missing or cracked cap is an open invitation for storm debris to enter the line. And if your home has a history of monsoon backups, consider a backwater valve on the main sewer line. The valve allows wastewater to exit normally but closes automatically when flow reverses, making it a highly effective long-term measure against sewage flowing back into your home from a surcharging municipal main.
During a Storm
When a heavy monsoon is actively running, the municipal system may already be at or near capacity. Every gallon you add to your drain system increases back-pressure on the sewer lateral. Avoid running the dishwasher, washing machine, or taking showers while the storm is at peak intensity. If water is backing up into a floor drain, stop all water use in the home immediately and call a drain service company rather than attempting to plunge or snake the line yourself. At that point the problem is in the main lateral or the municipal connection. It is not something a household tool can fix.
Getting Ahead of Monsoon Drain Problems
Most of what we see every monsoon season was avoidable. A pre-season camera inspection on an aging lateral, a cleaned sewer line, a properly seated cleanout cap: these are small investments compared to the cost of a flooded floor drain, water-damaged flooring, and emergency service in the middle of August. Caliche soil and intense summer storms are part of life in Farmington. The plumbing systems underneath your home don’t have to be casualties of them.
R.A. Biel Plumbing & Heating, Inc. has been helping Farmington homeowners protect their drains and sewer systems through more than three decades of monsoon seasons. To get your lateral inspected before the season peaks, give us a call at (505) 278-5112.