Sewer Smell in Las Vegas: How to Find the Cause Safely

What That Sewer Smell Actually Is?

When a home smells like sewage, most people assume something is rotting somewhere. What they are really smelling is a mix of gases coming up from the drain and waste system. That sewer gas matters for both comfort and safety, so it pays to understand what it is made of.

The chart below breaks down the main parts of sewer gas and what each one means for a household.

Gas Component	What It Is	Why It Matters
Hydrogen sulfide	Produces the rotten egg odor	Irritating and toxic at high levels
Methane	Colorless, mostly odorless	Flammable and can displace oxygen
Ammonia	Sharp, biting smell	Irritates eyes and airways
Carbon dioxide	Byproduct of waste breakdown	Reduces breathable air in tight spaces

Sewer Gas and the Rotten Egg Odor

Sewer gas forms as waste and organic material break down inside drain lines and the main sewer. As bacteria feed on that material, they release a blend of gases. The two that matter most for homeowners are hydrogen sulfide and methane.

Hydrogen sulfide is the one responsible for that classic rotten egg smell. Even tiny amounts are easy to detect, which is why a small leak can make a whole hallway smell off. The human nose can pick it up at very low concentrations, long before levels become dangerous.

Methane is trickier because it is mostly odorless on its own. It tags along with the hydrogen sulfide, so when someone smells eggs, methane is usually present too. That matters because methane is flammable, which is part of why a strong sewer odor should never be ignored.

Together these gases tell a story. A faint smell usually means a small amount of gas is sneaking past a barrier somewhere, while a heavy, constant odor often points to a larger break or backup that needs a professional look.

Why the Smell Comes and Goes

One of the most common things we hear is that the smell only shows up at certain times. An intermittent odor often confuses people, because they assume a real problem would smell bad all day. In reality, the on-and-off nature is a clue, not a reason to relax.

Heat plays a big part. As a home warms up during a Las Vegas afternoon, gases expand and rise more freely through drains and gaps. That is why a smell can feel stronger by late day and lighter overnight when things cool down.

Water use also changes the picture. Running a washing machine or flushing several toilets can pull air through the pipes and push odors into the living space for a few minutes. When the house goes quiet, the smell may settle again.

Air pressure shifts matter too. When wind hits the roof vents or the HVAC kicks on, pressure inside the drain system changes and can force gas up through a weak point. These swings explain why the same smell appears and disappears without any obvious reason.

Health Risks Worth Knowing

Most short exposures to a faint sewer smell will not hurt a healthy adult, but the odor is still a real health risk worth respecting. The body reacts to even low levels of these gases, and ignoring them is never a good idea.

At low concentrations, gas exposure often causes headaches, nausea, dizziness, and eye or throat irritation. Many homeowners chalk these up to allergies or a long workday, not realizing the air in the house is the cause.

At higher concentrations, hydrogen sulfide becomes far more serious. It can dull the sense of smell quickly, which is dangerous because people stop noticing the very gas that is harming them. According to the CDC and NIOSH, high levels can cause loss of consciousness and worse.

Children, older adults, and anyone with breathing problems feel these effects sooner. If a smell is strong enough to cause symptoms, treat it as urgent and get fresh air moving right away rather than waiting it out.

Why Desert Homes Notice It More

Homes in a dry climate often deal with sewer odors more than homes in humid regions. The reason comes down to how fast water disappears from the plumbing system here in Southern Nevada.

Every drain relies on a small amount of standing water to block gas. In our dry desert air, that water evaporates faster than it would in a damp climate. A guest bathroom that goes unused for two weeks can lose enough water through evaporation to let gas slip in.

Summer heat speeds this up dramatically. When indoor temperatures climb and the air is bone dry, the water in a rarely used trap can vanish in days instead of weeks. That is why the smell so often shows up during the hottest months.

Add in tightly sealed, energy-efficient homes that trap air inside, and the odor lingers instead of clearing. The combination of dry air, high heat, and sealed houses makes Las Vegas homes especially prone to noticing these smells.

Safety Steps to Take Before You Investigate

Before anyone starts hunting for the source, a few sewer gas safety steps come first. The goal is to protect the household, improve ventilation, and rule out anything dangerous before poking around drains and pipes.

• Get fresh air moving through the home as fast as possible
• Avoid anything that could ignite flammable gas
• Know the warning signs that mean it is time to leave
• Call the right people for the right problem

Open Windows and Get Airflow Moving

The first move is simple: open windows and doors to vent the home. Good ventilation dilutes the gas quickly and makes the space safer while the source is found. In a tightly sealed Las Vegas house, this step matters more than most people expect.

Cross-ventilation works best. Open windows on opposite sides of the home so air flows through instead of just sitting. A box fan placed in a window pointing outward helps pull stale air out and pull fresh air in.

Turn on exhaust fans in bathrooms and the kitchen as well. These fans push gas-laden air outside and speed up the airflow. In summer, this can fight the heat, so balance comfort with safety and run the AC fan to keep air circulating.

Clearing the air also makes it easier to track the smell later. Once the heavy odor thins out, it becomes simpler to walk room by room and find where the smell is strongest.

Avoid Open Flames and Sparks

Because methane is a flammable gas, fire safety comes before anything else. If the odor is strong, no one should light a match, a candle, or a gas stove until the air is clear and the source is known.

Pilot lights and gas appliances deserve extra caution. If a heavy smell fills the home, avoid switching appliances on or off, since a spark from a switch can be enough to ignite built-up gas in rare cases.

This is also a reason to take a strong, persistent rotten egg smell seriously. Utility companies add a similar odor to natural gas on purpose, so a sewer-like smell can sometimes be confused with a gas leak. When in doubt, treat it as the more dangerous possibility.

Keep these habits in place until a professional confirms the air is safe. A few minutes of caution is worth far more than gambling with flammable gas inside a closed home.

Know When to Leave the House

Most sewer smells are a nuisance, not an emergency. But there are clear signs that mean evacuation is the right call rather than investigation. Knowing them ahead of time helps a family act fast.

Leave the home if the smell is overpowering, if multiple people feel dizzy, sick, or short of breath, or if anyone notices a hissing sound near a gas line. These can signal a gas leak or a dangerous buildup that no homeowner should try to handle alone.

Get everyone outside, including pets, and move away from the structure. Once outside and safe, call for help rather than going back in to open more windows or find the source.

Do not use a phone, light switch, or garage door opener inside if a gas leak is suspected. Make the call from a safe distance outdoors, and wait for professionals to clear the home before returning.

Who to Call in Southern Nevada

The right call depends on the source. If the rotten egg smell might be natural gas, contact Southwest Gas right away, since they handle suspected gas leaks across the valley. Their emergency line is staffed around the clock.

If the odor clearly comes from drains, toilets, or the sewer, a licensed plumber is the right choice. Our team handles sewer odor calls daily, and we can pinpoint whether the issue is a dry trap, a bad seal, or something deeper in the line.

For any situation that feels dangerous, call 911 first and let trained responders secure the home. There is no harm in being cautious when flammable gas might be involved.

When the smell is plumbing related, our emergency plumbing service can respond quickly. We also offer a gas safety inspection for homeowners who want both bases covered.

Most Common Causes of Sewer Smell in Las Vegas Homes

Across thousands of service calls, the same handful of culprits keep showing up. A dry P-trap, a bad toilet seal, a blocked vent, and a cracked sewer line cover the vast majority of drain odor problems we find in valley homes.

The table below shows how common each cause is and how hard it usually is to fix.

Cause	How Common	Typical Fix Difficulty
Dried-out P-trap	Very common	Easy
Failed toilet wax ring	Common	Moderate
Blocked vent stack	Less common	Moderate
Cracked sewer line	Occasional	Hard

Dried-Out P-Traps in Guest Baths

The most frequent cause we see is a dried-out P-trap, and it almost always strikes the least-used bathroom. Homes near Summerlin and Henderson often have a guest bath or two that sees water maybe once a month.

The P-trap is the curved pipe under every sink, tub, and floor drain. It holds a small pool of water that blocks sewer gas from rising into the room. When no one runs that fixture, evaporation slowly empties the trap.

In our dry air, that pool can disappear in a couple of weeks. Once it is gone, there is nothing left to stop the gas, and the bathroom starts to smell. The fix is often as simple as running the water for thirty seconds to refill the trap.

Floor drains in laundry rooms and garages cause the same problem and get overlooked because no one looks at them. A monthly splash of water down each one keeps the traps full and the smell away.

Broken or Loose Toilet Seals

A toilet sits on a wax ring that seals it to the drain flange in the floor. When that wax ring fails, gas escapes around the base of the toilet and into the bathroom. This is one of the more common sources we trace on service calls.

A failing toilet seal often comes with subtle signs. The toilet may rock slightly when someone sits down, or the floor around the base might feel soft or look stained. Any movement breaks the seal further and lets more odor through.

Sometimes the smell is the only clue. The wax ring can crack or flatten over years of use, even on a toilet that looks perfectly fine. A trained eye can usually spot the issue in minutes.

Replacing a wax ring is a routine repair, but it requires pulling and resetting the toilet correctly so the new seal holds. Our pipe and fixture services cover this kind of work across the valley.

Clogged or Blocked Vent Stacks

Every home has a vent stack, a pipe that runs up through the roof to let sewer gases escape safely outside. When that roof vent gets blocked, the gases have nowhere to go but back into the home through drains.

In Las Vegas, these vents get clogged by blown-in debris, leaves, and even nesting birds. We have pulled out everything from tennis balls to bird nests during inspections. A partial block is enough to disrupt the airflow that keeps drains working right.

A blocked vent stack often shows up alongside gurgling drains and slow draining sinks. The trapped pressure pulls water out of P-traps, which then lets gas in from two directions at once.

Clearing a vent stack is not a job for a homeowner balancing on a hot roof. Our team has the equipment to clear the blockage safely and confirm the vent is flowing as it should.

Cracked or Shifting Sewer Lines

The most serious cause is a cracked or broken sewer line underground. When a drain line cracks, gas can seep up through the soil and into the home, and waste can leak into the ground.

Soil movement is a real factor here. The expansive desert soil around the valley swells and shrinks with moisture changes, which stresses buried pipes over time. Older lines crack under that constant push and pull.

A sewer line crack often produces a smell that will not go away no matter how many traps get refilled. That persistence is the giveaway that the problem is structural rather than a simple dry drain.

Finding a buried crack takes a camera inspection, not guesswork. Our drain and sewer services include video inspection to locate the exact spot without tearing up the whole yard.

How Older Las Vegas Neighborhoods Face Different Risks

The age of a home and its neighborhood change the odds of certain problems. Older homes with cast iron pipe behave very differently from newer master-planned builds, and local soil conditions add another layer.

Here is a quick look at how risks vary across the valley.

Area	Typical Era	Common Odor Risk
Huntridge / Downtown	1940s-1960s	Corroded cast iron drains
Sunrise Manor / East LV	1960s-1980s	Soil movement cracks
Mountains Edge / Skye Canyon	2000s-present	Venting and settling issues
Condo / townhome communities	Varies	Shared line complications

Cast Iron Pipes Near Downtown and the Historic District

Many mid-century homes near the Huntridge area and the historic district still run on the original cast iron drains. These pipes were built to last decades, but most have been in the ground far longer than they were meant to be.

Cast iron corrodes from the inside out. Over fifty or sixty years, the pipe walls thin, rust flakes off, and small holes or cracks form. Each one becomes a path for sewer gas to escape into the home.

Corrosion also roughens the inside of the pipe, which catches waste and slows drainage. That buildup adds to the odor and makes clogs more likely as the years pass.

For homes in these older pockets, a camera inspection often reveals just how much pipe is left. In many cases, replacing aging cast iron with modern materials solves the smell and prevents future backups at the same time.

Soil Movement in East Las Vegas and Sunrise Manor

East Las Vegas and Sunrise Manor sit on ground with a lot of expansive soil. This type of soil expands when it gets wet and shrinks as it dries, putting steady stress on anything buried in it.

Sewer and drain lines take the brunt of that movement. Over years of swelling and shrinking, joints separate and pipes crack, especially the older clay and cast iron lines common in these neighborhoods.

A separated joint may leak gas without any visible sign at the surface for a long time. Homeowners often notice a faint, persistent smell long before any other symptom appears. Our team serves Sunrise Manor regularly and sees this pattern often.

Because the soil keeps moving, a one-time patch is not always enough. We look at the whole line condition to recommend a repair that will hold up against the ground around it.

Newer Builds in Mountains Edge and Skye Canyon

Newer does not always mean problem-free. Master-planned communities like Mountains Edge and Skye Canyon see their own odor issues, usually from venting problems or ground that is still settling.

New construction homes can have vent pipes that were never quite finished or got partially blocked during the build. A small mistake in the venting can let gas back up into the home long after the builder is gone.

Settling ground is another factor. As fresh fill dirt compacts under a new home over the first several years, pipes can shift and joints can loosen. Even a brand-new house can develop a sewer smell this way.

The fixes are usually straightforward once the cause is found. A camera check sorts out whether the issue is venting, a settling joint, or simply a dry trap in a rarely used room.

HOA Rules and Shared Sewer Lines

Condo and townhome communities add a wrinkle that single-family homes do not have: shared sewer lines. A shared lateral line means several units drain into one pipe before it reaches the city main.

When a smell or backup starts in a shared line, figuring out who is responsible gets complicated. The HOA may own part of the line while individual owners handle the rest, and the dividing point is not always obvious.

This matters for both repairs and cost. A homeowner might pay for a fix that turns out to be the association's responsibility, or vice versa. Reading the HOA documents and getting a clear diagnosis helps avoid that.

We help owners in these communities document exactly where the problem sits in the line. A camera inspection that pinpoints the location often settles the question of who pays before any repair begins.

How to Track Down the Source Yourself

Before calling a pro, a homeowner can often narrow down the problem with a few safe steps. The goal of this troubleshooting is to find the sewer smell or at least point to the right room, which saves time and money.

Run Water in Every Drain

The single best first step is to run water in every drain in the house. This refills the P-trap water in fixtures that have not been used and is the fastest way to fix the most common cause.

Walk through and run each sink, shower, and tub for about thirty seconds. Do not forget the floor drain in the laundry room, garage, or basement-style utility area, since those are the ones people always miss.

Flush every toilet too, including the guest bath that rarely gets used. A flush refills the bowl trap and the larger trap below it, both of which can dry out over time.

If the smell fades over the next day or two, a dry trap was almost certainly the cause. This simple routine fixes a surprising number of odor calls before they ever become service appointments.

Check Around Toilets and Tubs

If running water does not solve it, the next stop is the base of each toilet. A failing toilet base seal is a frequent source, and the signs are easy to check for at home.

Gently try to rock the toilet side to side. If it moves at all, the seal underneath may be broken and letting gas escape. A stable toilet should feel solid and not shift under light pressure.

Look at the caulk seal around the base and the tub. Cracked, missing, or peeling caulk can let odor and moisture move where they should not. Stains or soft spots on the floor near the base are another red flag.

Note which fixtures feel loose or look damaged. That information helps a plumber go straight to the problem instead of testing everything from scratch.

Smell-Test Each Room

Finding the odor source often comes down to a careful room-by-room smell test. Once the air has cleared a bit, walk slowly through the home and notice where the smell is strongest.

Get close to drains, toilet bases, and floor vents in each room. The spot where the odor hits hardest usually sits near the failing fixture or pipe. A consistent strongest point is a solid clue.

Pay attention to timing as well. If a room only smells after a shower or a load of laundry, the problem may tie to how water and air move through that part of the system.

Write down what each room smells like and when. Patterns that seem random at first often make sense once they are tracked over a few days.

Inspect the Cleanout and Yard

The exterior cleanout is a capped pipe that gives access to the main sewer line. It usually sits near the house in the yard or along the side, often a few inches above the ground.

A strong sewer smell right at the cleanout can mean a blockage or break further down the line. If the cap is loose or missing, that alone can let odor out, so it is worth checking that it is sealed.

While outside, scan the yard for soggy spots or unusually green patches in an otherwise dry desert lawn. A yard leak from a cracked sewer line feeds water and waste into the soil, and plants respond to it.

If the cleanout reeks or the yard shows wet patches, that points toward an underground problem. At that stage, a camera inspection is the right next move rather than more home testing.

When the Smell Means a Bigger Plumbing Problem

Sometimes a sewer smell is the first warning of real sewer line damage or an impending drain backup. Knowing these signs helps a homeowner act before a small issue turns into a flooded floor.

Slow Drains and Gurgling Sounds

When several drains slow down at once and the air smells off, the problem is often deeper than any single fixture. A slow drain in one sink is usually a local clog, but multiple slow drains point to a main line clog.

Gurgling sounds add to the story. When a toilet or sink burps and bubbles as it drains, air is getting trapped and forced back through the water. That trapped air carries sewer gas with it.

This pattern means the blockage sits somewhere the whole house drains through. Water backs up behind it and pulls air through traps, releasing odor along the way.

At this point, a hydro jetting or rooter service often clears the line. Catching it at the gurgling stage is far better than waiting for a full backup.

Sewage Backing Up Into Fixtures

The clearest emergency sign is sewage rising into tubs, showers, or toilets. When dirty water comes up instead of going down, the main line is blocked or broken and the system has nowhere to send waste.

This is not a wait-and-see situation. Standing sewage carries bacteria and creates a health hazard in the home, and it can spread quickly across floors and into other rooms.

Stop using water right away to avoid adding to the backup. Every flush or drain run pushes more waste toward the blockage and makes the mess worse.

A backup like this needs immediate help. Our sewage backup cleanup team handles these calls and works to stop the source and clean the affected area safely.

Soggy Spots or Greener Patches in the Yard

An underground leak does not always announce itself indoors. Often the first sign shows up in the yard as a soggy patch or a stretch of grass that looks greener than everything around it.

In a dry desert yard, extra moisture stands out. A broken sewer line leaks water and nutrients into the soil, and plants soak it up, growing thicker and greener over the leak.

Soft, muddy ground that never seems to dry is another warning. It means water is reaching the surface from a pipe below, and that pipe is likely cracked or separated at a joint.

These yard signs deserve a camera inspection to confirm the location and size of the break. Finding it early keeps the repair smaller and the cost lower.

Recurring Odors After a Quick Fix

A smell that keeps coming back after a simple fix is telling you something. If refilling traps and checking seals only helps for a few days, a recurring odor usually means a structural pipe failure.

This is the pattern that separates a minor issue from a real one. Dry traps stay fixed once refilled, but a cracked line or failing joint keeps leaking gas no matter what a homeowner does inside.

Each return of the smell is a clue that the source has not actually been addressed. Chasing it with air fresheners or repeated trap refills only masks the problem temporarily.

When odors keep returning, it is time for a professional diagnosis. A camera inspection finds the underlying pipe failure so the repair fixes the cause instead of the symptom.

How Active Plumbing Finds and Fixes the Source

When homeowners call us about a sewer smell, our job is to find the exact source fast and fix it right. At Active Plumbing, we lean on camera inspection, smoke testing, and a range of repair methods proven on valley homes.

Here is how our diagnostic and repair tools match up to different problems.

Tool or Method	What It Finds	Best For
Sewer camera	Cracks, clogs, breaks in line	Underground and hidden pipes
Smoke test	Gas escape points	Walls, floors, vent leaks
Wax ring replacement	Failed toilet seals	Odor at toilet base
Pipe repair / replacement	Damaged sections	Cracked or corroded lines

Video Camera Drain Inspections

A sewer camera is the most useful tool we carry for odor calls. It lets us see inside the drain and sewer without digging up the yard or opening a wall to guess at the problem.

We feed a waterproof camera on a flexible cable through the line and watch a live feed. Cracks, clogs, root intrusion, and broken joints all show up clearly on screen as we move through the pipe.

The camera also tracks the exact depth and location of any problem. That means when a repair is needed, we dig in one precise spot instead of trenching the whole run. Our sewer camera inspection service is the foundation of an accurate diagnosis.

For homeowners, this drain inspection turns guesswork into facts. They can see the issue themselves and understand exactly why a repair is needed before any work starts.

Smoke Testing to Find Hidden Leaks

Some gas leaks hide in places a camera cannot reach, like cracks behind walls or under flooring. For these, smoke testing is the answer. We push a non-toxic, visible smoke through the drain system under light pressure.

The smoke follows the same path the gas does. Wherever it escapes, we see it puff out: around a toilet base, through a wall gap, from a bad vent, or up through the floor. That visual makes leak detection precise.

The smoke is harmless and clears quickly, so it is safe to use inside an occupied home. It simply reveals every weak point in the system at once, which a nose alone could never pinpoint.

Smoke testing is especially handy for those frustrating intermittent smells. When an odor seems to come from nowhere, the smoke shows exactly where the gas is getting in.

Repairs From Simple Seals to Pipe Replacement

Once we find the source, the repair can range from quick to involved. Many calls end with a simple wax ring replacement, reseating the toilet with a fresh seal that stops the odor for good.

Other jobs need more. A cracked section of pipe may call for a spot repair, where we replace just the damaged length while leaving the rest of the line in place. This keeps cost and disruption down.

For badly corroded cast iron or repeatedly failing lines, full pipe repair or replacement makes more sense. Our sewer line repair and replacement service covers everything from small fixes to complete line swaps.

We always match the repair to the actual problem. A homeowner with a dry trap does not need a new line, and one with crumbling cast iron should not get a patch that fails in a month.

Same-Day Service Across the Valley

A sewer smell is not something most families want to live with overnight. That is why we offer same-day service for urgent odor calls whenever our schedule allows.

Our coverage runs across the whole valley, from Las Vegas proper out to Centennial Hills in the northwest and down to Green Valley in Henderson. We know the neighborhoods, the soil, and the common pipe issues in each.

Quick response matters most when a smell hints at a backup or a leak. Getting a camera on the line the same day can stop a small problem from becoming a flooded floor.

Homeowners in Henderson and surrounding areas can reach our team for fast help with any sewer odor. We aim to find the source and lay out clear options on the first visit.

How to Keep Sewer Smells From Coming Back

Once the smell is gone, a little routine drain maintenance keeps it from returning. Most prevention steps take only a few minutes a month and are easy for any homeowner to manage.

Run Water in Spare Bathrooms Monthly

The simplest habit to prevent sewer smell is running water in spare bathrooms once a month. This keeps the P-trap full in fixtures that otherwise sit dry and let gas in.

Set a reminder for the first of each month. Run every sink, shower, and tub in the guest bathroom for thirty seconds, and flush the toilet a couple of times to refresh the bowl.

Do not skip the floor drains in the garage and laundry room. A cup or two of water down each one keeps those traps sealed, since they are the ones that dry out fastest in our climate.

This small bit of P-trap maintenance prevents the single most common odor problem we see. A few minutes a month saves a service call and a smelly hallway.

Keep Drains and Garbage Disposals Clean

Clean drains smell better and clog less. Regular drain cleaning clears the buildup that feeds bacteria and creates odor, especially in kitchen lines that handle food and grease.

Avoid pouring grease down the sink, since grease buildup is a leading cause of slow drains and smells. Let it cool and toss it in the trash instead of rinsing it into the pipes.

For the garbage disposal, run cold water while it works and grind a few ice cubes now and then to keep the blades clean. A little baking soda followed by hot water helps cut odor without harsh chemicals.

When drains slow down despite cleaning, a professional flush goes deeper than home methods. Our team can clear lines fully and reset the system to flow freely again.

Schedule Routine Camera Checks for Older Homes

Homes with aging cast iron or clay pipes benefit from a routine inspection every few years. A periodic camera check catches small cracks and corrosion before they grow into leaks or backups.

This is smart for the older neighborhoods we mentioned earlier, like Huntridge and parts of Sunrise Manor. Older pipes deteriorate slowly, and a camera spots trouble while repairs are still simple and cheap.

A routine inspection also gives a clear baseline. Knowing the current condition of the line helps a homeowner plan ahead instead of being surprised by an emergency.

For homes selling or changing hands, a camera check brings peace of mind to both sides. It confirms the sewer line is sound or flags issues before they become a costly dispute.

Watch for Early Warning Signs

Catching problems early keeps them small. A few subtle clues serve as early warning signs that the sewer system needs attention before a real smell or backup hits.

Watch for faint odors that come and go, slow drains that take longer to clear, and gurgling sounds after flushing. Any one of these on its own is minor, but together they suggest a developing issue.

Keep an eye on the yard too. A new soft spot or a patch of grass that suddenly looks greener can signal an underground leak long before it reaches the house.

When these signs show up, a quick call gets ahead of the problem. We would rather check a small clue than clean up a backup, and so would every homeowner we serve.

Final Thoughts

A sewer smell in a Las Vegas home is almost always solvable once the source is found. Most cases trace back to a dry P-trap, a failing toilet seal, a blocked vent, or a cracked line, and each has a clear fix.

Safety comes first: get airflow moving, avoid open flames, and know when to step outside and call for help. From there, a few simple home checks often narrow the problem down before a pro even arrives.

When the smell points to something deeper or keeps coming back, our team is ready to help. Contact Active Plumbing or call us for a consultation, and we will find the source and fix it right, anywhere across the valley.

Frequently Asked Questions

Is sewer gas dangerous to breathe?

Low levels of sewer gas usually cause minor irritation like headaches, nausea, or watery eyes. Higher concentrations are far more serious and can cause dizziness, loss of smell, and even loss of consciousness. If the smell is strong, several people feel sick, or anyone struggles to breathe, leave the home, get fresh air, and call for help right away rather than trying to wait it out.

Why does my bathroom smell like sewer only sometimes?

An intermittent odor usually comes from a dried-out P-trap, a venting problem, or air pressure changes. As a home heats up or water gets used, gases expand and push through weak spots, then settle again when things cool. In our dry climate, traps in rarely used bathrooms evaporate fast, so the smell appears and fades depending on time of day and how often the fixture runs.

Can a dried-out drain really cause the smell?

Yes, and it is the most common cause we find. Every drain holds a small pool of water in its P-trap that blocks sewer gas. When a fixture sits unused, that water evaporates, especially in dry Las Vegas air, and gas flows freely into the room. Running water in the drain for thirty seconds refills the trap and usually clears the odor within a day.

How do I know if the smell is from the toilet?

Check the base of the toilet first. Gently rock it side to side, and if it moves at all, the wax ring seal may be broken and leaking gas. Look for gaps, cracked caulk, water stains, or soft flooring around the base. If the smell is strongest right at floor level near the toilet, a failed seal is the likely cause and needs replacement.

What does it cost to fix a sewer smell in Las Vegas?

Costs vary widely by cause. A simple fix like refilling a trap costs nothing, while replacing a toilet wax ring is a modest repair. A camera inspection runs higher but pinpoints the exact issue, and sewer line repairs or replacements cost the most. We always diagnose first and lay out clear options so homeowners know what they are paying for before any work begins.

Should I call Southwest Gas or a plumber?

It depends on the smell. Natural gas has a rotten egg odor added to it, so a strong, sudden smell near a gas appliance could mean a gas leak, and Southwest Gas should be called immediately. If the odor comes from drains, toilets, or the sewer and smells more like waste, a licensed plumber is the right call. When unsure, treat it as gas and stay safe.

Why is the smell worse in summer?

High summer heat speeds up evaporation in P-traps, so the water that blocks gas disappears faster. Warm air also makes gases expand and rise more freely through drains and gaps. Combined with tightly sealed, air-conditioned homes that trap odors inside, these factors make sewer smells noticeably stronger during the hottest months in the valley.

Can a sewer smell mean a cracked pipe under my house?

It can. A persistent smell that returns no matter how many traps you refill often points to a cracked or separated sewer line. The expansive desert soil here swells and shrinks with moisture, which stresses buried pipes until joints break or cracks form. Gas then seeps up through the ground. A camera inspection confirms whether the line is the source.

How fast can a plumber find the source?

In most cases we can locate the source the same day we arrive. A camera inspection of the drain and sewer line takes under an hour for many homes, and smoke testing quickly reveals hidden leak points in walls and floors. Once we see the problem, we explain it clearly and outline repair options on the spot.

Does my HOA cover sewer line repairs?

It varies by community and where the problem sits. In condo and townhome communities with shared lateral lines, the HOA may own part of the line while individual owners are responsible for the rest. The dividing point is not always obvious. A camera inspection that documents the exact location of the issue helps settle who pays before any repair starts.