Understanding Sewer Lines

Expert plumbers can provide appropriate advice on locations where you can still use this sewer line.

Drainage issues are among the most common headaches homeowners face, and the root of many of these problems lies in the sewer lines beneath our homes and streets. While most people rarely think about what happens after water swirls down the drain, understanding what is a sewer line, the different types of sewage lines, and how they function is crucial for maintaining a safe and healthy home. As professional plumbers, we’re here to guide you through the essentials of sewerage line systems, their maintenance, and why professional expertise is key to keeping your plumbing trouble-free.

What is a sewer line?

A sewer line is an underground pipe system that carries wastewater away from your home to either a municipal treatment plant or a private septic system. These pipes are the backbone of modern sanitation, quietly working around the clock to remove waste and keep our living spaces clean. When people ask, “what is a waste line?” or “what is a sewage line?” they usually refer to these vital conduits.

A typical home’s plumbing system connects all sinks, toilets, showers, and appliances to a main waste line, which joins the larger municipal or neighborhood sewer system. If you’ve heard the term sanitary line plumbing, that refers to the specific pipes designed to handle only wastewater from homes and businesses, keeping it separate from rainwater or other runoff.

Sanitary line vs sewer line

The terms sanitary line and sewer line are sometimes used interchangeably, but important distinctions exist. A sanitary sewer line is specifically designed to directly transport wastewater from bathrooms, kitchens, and laundry rooms to a treatment facility. These lines are sealed and constructed to prevent leaks and contamination, ensuring that waste is safely processed and treated before reentering the environment.

On the other hand, the term "sewer line" can refer to any pipe that carries waste, including combined systems that handle both sewage and stormwater. Understanding the difference between a sanitary line and a sewer line is important for homeowners, especially when considering repairs, upgrades, or new installations.

The three main categories of sewer lines

Not all sewer lines are created equal. Depending on the age of your home, local infrastructure, and regional climate, your property may be connected to one or more types of sewer lines. Here’s a closer look at the three main categories:

Sanitary sewer lines

Sanitary sewer lines are the most common in modern urban and suburban areas. These pipes are dedicated solely to transporting wastewater from homes and businesses to municipal water treatment plants. Because these lines handle only sewage, they are less prone to overflows during storms and are easier to maintain and repair.

Proper maintenance of sanitary sewer lines is critical. Even a small leak can allow wastewater to escape, potentially contaminating groundwater or nearby streams. This contamination can lead to widespread infections and water-borne diseases, posing a serious health risk to the community. That’s why relying on professional plumbers for inspections, repairs, and routine maintenance is essential. Our expertise ensures your sanitary lines remain leak-free and fully functional.

Combined sewer lines

You might have a combined sewer line if your home is older, especially in historic neighborhoods. These systems were designed to carry wastewater and stormwater in a single pipe. While this approach made sense when infrastructure budgets were tight, it has significant downsides today.

Combined sewer lines can easily become overwhelmed during heavy rains, causing untreated sewage and stormwater to overflow into the environment. This increases the cost of water treatment and raises the risk of pollution and health hazards. If you’re unsure what type of system your property uses, a professional plumbing inspection can provide clarity and peace of mind.

Expert plumbers can also advise on whether it’s still appropriate to use a combined system in your area and, if so, how to minimize the risk of overflows. In some cases, upgrades or modifications may be recommended to bring your plumbing up to modern standards.

Storm sewer lines

Storm sewer lines are designed to collect and channel rainwater away from streets, roofs, and driveways, keeping it separate from the sanitary sewer system. These pipes help prevent flooding and reduce the risk of sewage backups during storms. Common stormwater solutions include catch basins, gutters, and dry wells.

Proper installation of storm sewer lines is essential for protecting your home’s foundation and landscaping. Professional plumbers use soil testing and site analysis to determine the best location and size for stormwater systems, ensuring efficient drainage without unnecessary expense. By keeping stormwater and sewage separate, these systems help maintain the integrity of both your home and the wider environment.

Maintaining sewer lines

Like any part of your home, sewer lines require regular care to function properly. Neglect can lead to clogs, leaks, and even catastrophic failures. Here are some of the most common issues we see as plumbing professionals—and how we help homeowners address them.

Root infiltration

One of the most persistent threats to sewer lines is root infiltration. Trees and shrubs naturally seek out moisture; even a hairline crack in your sewer line can attract roots. Over time, these roots can grow into the pipe, blocking the flow of wastewater and causing backups.

If you’re planning new landscaping or suspect roots are already causing problems, it’s wise to consult a professional plumber. We can advise on the best location for new sewer lines to avoid root intrusion, recommend tree removal when necessary, and perform root treatments to clear existing blockages. We may suggest pipe repairs or replacements to restore proper flow in severe cases.

Broken sewer lines

A broken sewer line is a serious issue that demands immediate professional attention. Cracks, breaks, or collapses can occur due to age, shifting soil, heavy vehicles, or construction work near your property. When a sewer line fails, wastewater can leak into the ground, contaminating soil and potentially reaching drinking water supplies.

Signs of a broken sewer line include persistent foul odors, slow drains throughout the house, soggy patches in your yard, and unexplained increases in your water bill. If you notice these symptoms, don’t hesitate to call a qualified plumber. We use advanced diagnostic tools to pinpoint the problem and recommend the most effective repair options, whether trenchless pipe lining, spot repairs, or full replacement.

Occupant behavior

How you use your plumbing can greatly impact the health of your sewer lines. Flushing fats, oils, and grease down the drain is a common mistake that leads to clogs and backups. While pouring hot water might seem like a quick fix, it often only moves the problem further down the pipe, where it can solidify and cause even bigger issues.

Other problematic items include wipes (even those labeled “flushable”), feminine hygiene products, and paper towels. These materials don’t break down easily and can accumulate in your pipes, creating stubborn blockages. When in doubt, remember: only toilet paper and human waste should go down the toilet.

If you’re experiencing frequent clogs or slow drains, it’s time to call in the professionals. We can thoroughly inspect your system, clear any obstructions, and suggest best practices to keep it running smoothly.

Professional maintenance and inspections

Regular maintenance is the best way to prevent sewer line problems before they start. As professional plumbers, we recommend annual inspections of your sewer system, especially if your home is older or you’ve experienced issues. During an inspection, we use video cameras to examine the inside of your pipes, looking for signs of wear, cracks, root intrusion, or buildup.

Routine cleaning can also help keep your sewer lines clear and free-flowing. Professional-grade equipment allows us to remove even the toughest blockages without damaging your pipes. For homes with septic systems, regular pumping and inspection are essential to prevent backups and extend the life of your system.

Upgrading and replacing sewer lines

Sometimes, maintenance isn’t enough, and an upgrade or replacement is needed. Advances in plumbing technology have made it easier than ever to replace old or damaged sewer lines with minimal disruption. Trenchless repair methods, for example, allow us to fix pipes without digging up your yard, saving time and money.

If you’re planning a renovation, adding new bathrooms, or expanding your home, consult a professional plumber about your sewer system. We can assess whether your existing lines are up to the task and recommend upgrades if needed. Investing in modern, durable pipes can prevent headaches and costly repairs.

Why professional services matter

Sewer lines are complex systems that require specialized knowledge and tools to maintain and repair. Attempting to fix problems yourself can lead to further damage, health hazards, and even legal issues if local codes are violated. By working with licensed, experienced plumbers, you can be confident that your sewer system is in good hands.

We stay up to date with the latest industry standards and technologies, ensuring that every job is done safely and efficiently. From routine maintenance to emergency repairs, we aim to provide peace of mind and reliable service you can trust.

Understanding your sewer lines is more than just plumbing trivia—it’s an essential part of homeownership. Knowing the difference between sanitary, combined, and storm sewer lines and the importance of regular maintenance can help avoid costly problems and protect the family’s health.

If you have questions about your sewer system, suspect a problem, or simply want to schedule a routine inspection, don’t hesitate to contact a professional plumbing service. With the right care and expertise, your sewer lines will continue to do their important work quietly and efficiently, keeping your home clean, safe, and comfortable for years to come.

Trust the licensed plumber at Simba Plumbing when in need of leak detection and repair, sink installation and repair, toilet installation and repair, sewer services, water heaters, tankless water heaters, and automotive shutoff valve solutions in Phoenix. Our services are affordable and aim to offer the best results. Call today to book a service and ask about our special offers.