Septic vs. Sewer: What Homeowners Need to Know

If you're like most people, you probably don't spend much time thinking about wastewater.

But when you're buying a new home, it's a good idea to understand the essential role that wastewater management plays in maintaining a healthy, sustainable, and efficient living space. In fact, wastewater management is one of the most important considerations you need to make during the homebuying process.

That's because homes quietly churn out substantial amounts of wastewater every day. Believe it or not, the average household in the United States produces around 138 gallons of wastewater each day from places like the tap, shower, washing machine, toilet, and dishwasher.

But where does it all go? There are two primary methods: septic and sewer systems. Let's explore how they work, their main differences, and their financial impact.

What is a septic system?

A septic system is a decentralized method of treating and removing wastewater independently on the property without connecting to a municipal sewer.

According to the EPA, more than one in five households in the U.S. depend on individual septic systems for wastewater treatment. They're common in suburban and rural areas.

How does a septic system work?

Septic systems funnel household waste into a single underground tank. Solid waste sinks to the bottom as sludge, lighter materials float as scum, and the partially treated liquid exits through an outlet pipe into a drain field for natural filtration back into the soil.

The pros and cons of using a septic system

Pros:

• No monthly sewer fees, leading to potential savings
• More environmentally friendly—uses natural biological processes
• Greater homeowner control over maintenance
• Effective in rural areas without municipal infrastructure

Cons:

• Installation costs can range from $10,000 to $25,000
• Prone to failure without proper maintenance
• Risk of groundwater contamination if poorly maintained
• Can negatively impact property value if outdated

What is a sewer system?

A sewer system is a network of pipes and infrastructure for collecting, moving, and treating wastewater at a dedicated treatment facility. Unlike septic, all processing happens off-property.

How does a sewer system work?

All wastewater flows through pipes into a main drain pipe, which connects to the municipal sewer line. Water enters the treatment plant for physical, biological, and chemical cleansing before returning to the environment.

The pros and cons of using a public sewer

Pros:

• Convenient and reliable—no tank pumping or on-site maintenance
• May increase property value
• No on-site wastewater storage or odors
• Municipality handles regulatory compliance

Cons:

• Monthly sewer fees (average $66.80/month)
• Homeowners still maintain the sewer lateral
• Dependent on municipal infrastructure
• Vulnerable to external disruptions

Septic tanks vs. city sewer: Maintenance costs

As a homeowner, you'll pay for wastewater maintenance either way. Here's how costs differ:

Septic tank maintenance costs

• Pumping: Required routinely to remove waste. Frequency depends on tank size, water usage, and household size.
• Inspections: Most homeowners inspect every 1–3 years.
• Repairs: Routine maintenance prevents costly repairs from clogs and damage.

Sewer system maintenance costs

• Monthly fees: Average $66.80/month, varying by location and usage.
• Connection fees: Required if your property isn't already connected.
• Sewer lateral maintenance: Homeowners are responsible for the pipe connecting their property to the main line.

Making the Right Choice

Both septic and sewer systems have pros and cons, making it important to consider your specific needs, budget, and property location. Understanding these differences will help you make a more informed homebuying decision.