If you have a septic system, sewage and wastewater drains from your home to an underground tank where it is treated and dispersed into the ground. Microorganisms (commonly called bacteria, although this includes protozoa, fungi, and other microbes) that develop naturally in the tank, digest and break down the organic matter. To help these microorganisms keep up with the sewage in your septic tank, every few years, you’ll pay around $450 to have your tank emptied, or pumped.

But if you own a home, are buying a home, or will be selling a home with a septic system, flushing out other important details can make your head swirl. How do you know when to pump, when NOT to pump, who should pump, how to reduce pumping frequency and save money?

To provide you with expert information, we talked to Jeff Lyons of R&L Septic in Springfield, Illinois and top real estate agent Sandi Van Camp of Hunt Real Estate in New York.

Table of contents

What’s in your septic tank and how it worksWhy you need to pump septic (and how often)Different tanks (What type of tank do I have?)How much it costs to empty your tankAdditional considerations (Costs for repair and maintenance services)How to know when your tank needs to be pumpedHow to reduce pumping frequencyShould you use bacterial drain cleaners and septic solutions?What to expect from a septic tank pump serviceHow you can cut expenses on your septic pumping serviceWhen a septic tank should NOT be pumpedWhere to find a reputable septic service to pump your tankHow septic system and tank condition affect resale value

What’s in your septic tank and how it works

As it breaks down, the sewage in your tank separates into three layers. Solids settle to the bottom in a layer called sludge. Oil and grease form the top layer, which is called scum. The layer between the sludge and scum is a liquid called effluent. Effluent is pre-treated wastewater that drains out of the tank into a shallow drainfield. Highly toxic methane gas rises to fill the space at the top of the tank.

A T-shaped outlet pipe in the tank prevents solids and scum from entering the laterals, which are perforated pipes that extend away from the tank below ground. Effluent is dispersed into porous materials (such as gravel or sand) which filters it before it percolates through the soil. Soil microorganisms treat the pre-treated wastewater as it percolates through the drainage field. A sturdy layer of geothermal fabric protects the drainfield (also called a leach field or cesspool) from ground contaminants and pests.

To keep your septic system in top condition, and prevent clogs that can damage laterals and cause sewage to back up into your home, you need to have your septic tank pumped every 3-5 years, or when sludge takes up more than one-third of the volume of your tank.

According to Van Camp, oftentimes you won’t have issues with a septic tank if you pump every three to five years. It’s scary when a homeowner says “I haven’t pumped my system in ten years.” As sludge settles to the bottom of the tank, the holding capacity of the tank is diminished. Clogs and backups occur if sludge reaches the T-shaped outlet. In addition, a full tank may cause methane and hydrogen gases to escape into your home.

As the sludge builds up, it becomes increasingly difficult for the microorganisms to break it down. Emptying the tank helps the microorganisms to catch up and keep your tank functioning properly. Microorganisms live in a perfectly balanced ecosystem (biome or colony), which can be disrupted, imbalanced, and even killed by household chemicals and inorganic materials that they can’t break down. An imbalanced ecosystem cannot properly break down sewage and your tank will overfill with sludge and scum until it clogs and overflows into your yard and your home.

Factors that increase how often you should have your septic pumped:

• Large household
• Insufficient tank size
• Large volumes of wastewater generated
• Large amounts of solids (such as from a garbage disposal)
• Tanks that have electric or moving parts
• Unusual groundwater saturation from precipitation or flooding

Different tanks (What type of tank do I have?)

A septic system may be anaerobic (oxygen-free), relying on microorganisms that thrive without oxygen. Aerobic tanks add oxygen to the tank for oxygen-loving microorganisms. Then, there are different types of septic systems depending on the volume and frequency of use, lot size, water table, groundwater saturation, and climate.

• Conventional gravity-fed systems are the most common type of tank in the U.S. Sewage and treated wastewater move through them naturally with wastewater. There are two types of gravity-fed systems:
  • Gravel systems treat and disinfect wastewater in one or two tanks and disperse into a drainage field where it is filtered through gravel.
  • Chamber systems have been around since the 1970s. They have a tank and open-bottom chambers that filter wastewater into an enclosed drainage trench.
• Conventional pump-fed systems have a separate pump tank and pump that pushes treated wastewater into the laterals (usually because the laterals are uphill).

Some of the more complex septic systems that have more tanks or moving parts require more maintenance in addition to regular pumping:

• Drip Distribution has a dose tank that holds and distributes wastewater through the shallow lateral system. A drip system may be aerobic or anaerobic. This system has a tank, a pump tank on a timer, and a hydraulic unit. It must be connected to electricity.
• Sand filtration systems pump treated wastewater into a concrete box full of sand where it is filtered before it is distributed into the drainage field.
• Mound distribution also uses sand filtration, in a raised bed drainage field. Wastewater flows from the tank into a chamber and is then pumped into the mound, filtered through sand and down into the soil. Mound systems require routine maintenance.

How much it costs to empty your tank

Methodology: HomeAdvisor tracks millions of user-submitted project estimates and correlates them with local professional estimates to deliver accurate averages.

Angi

Updated: June 10, 2021

Methodology: Angi tracks millions of user-submitted project estimates and correlates them with local professional estimates to deliver accurate averages.

Thumbtack

Updated: August 26, 2020

Methodology: Thumbtack tracks project estimates from the millions of people who use its site to connect with local professionals every year, then shares those prices on its site.

Real life estimate

Updated: October 28, 2021

Source: R & L Septic of Springfield, Illinois

Sewage in your home (cleaning service) $7 per square foot. To clean 1,500 square feet of a home would cost $10,500.

Location. If you live outside your septic company’s service location, you may be charged for the technician’s gas and time to drive out to your residence. Many times, this charge is a flat fee.

Pandemic inflation. Since the pandemic, supply chain issues and delayed manufacturing due to shortages in staff, closures, a shortage of shipping containers and trucks, rising fuel prices, and tariffs have inflated costs across the nation. This includes costs of materials and parts to service your septic tank as well as the cost of machinery and the cost to retain staff. According to Lyons, R & L Septic’s rates haven’t changed but will most likely go up approximately 7.7% January 1 and will still be competitive for their Midwest region. If you had your septic tank pumped prior to the pandemic, expect a higher service charge today.

It’s less expensive to pump your septic regularly than it is to repair a clog in your laterals or sewage backup into your home. However, if you notice these signs, you should contact a septic service to check your tank:

• Foul odor in your lawn. Sometimes a stinky drainfield will be the first sign your septic is overfilled, but it is always a definite sign.
• Slow draining sinks and toilets. Although one slow drain may indicate a clog inside your house, several slow drains are an indication that it’s time to pump your septic tank.
• Green or black, soggy or spongy grass. If you have standing water, bright green or slimy black grass that is spongy or soggy, you may have an issue in your drainage field that indicates your septic has a clog and needs to be pumped and your laterals need to be repaired.
• Foul odor in your home. A nasty odor coming from your sewer lines may not necessarily be from a full septic tank, but it is a good indication it may need to be pumped, especially if it hasn’t been serviced regularly or is due for service soon. In addition, if you don’t pump your tank regularly, methane and hydrogen sulfide may escape into your home through the sewer pipes. Methane smells like rotten eggs and hydrogen sulfide will make your eyes burn. Methane gas is both highly toxic and highly flammable.
• Sewer backup into your home. This is an unfortunate way to find out your septic needs to be pumped. At this point, you may have more costly repairs than cleaning your home and pumping your tank. If your septic has clogged laterals, you will pay more to have them repaired or replaced.

How to reduce pumping frequency

• Oil and grease
• Feminine products
• Diapers (including flushable diapers)
• Wipes (this includes septic-safe and biodegradable wipes)
• Floss
• Q-tips
• Napkins, paper towels
• Coffee grounds
• Litter
• Cigarette butts
• Condoms
• Harsh chemicals
• Medication

Should you use bacterial drain cleaners and septic solutions?

Microbial drain cleaners that claim to be septic safe can actually cause an imbalance in the septic ecosystem. In particular, RidX floods the septic system with aggressive bacteria that attack and kill the beneficial microorganisms in the tank and drainfield. Septic-safe vinegar and baking soda or a drain snake will effectively clear a clog.

Some manufacturers promote bacteria or microorganisms septic treatments for a healthy ecosystem in your septic. However, if you’re doing everything right, the microorganisms living in your tank won’t need help. Microorganism additions shouldn’t be used to avoid routine pumping and maintenance. This includes flushing yeast, which contains microscopic fungus that will compete with the bacteria in the tank.

Adding unnecessary microorganisms to a well-balanced tank can imbalance the tank and cause issues. Too many microorganisms can deplete the oxygen in a tank and kill the ecosystem. If you have concerns about how well your septic is functioning, contact a professional septic service, who can inspect your tank and, if necessary, recommend or apply an additive from a reputable manufacturer.

What to expect from a septic tank pump service

It will take approximately 20-30 minutes to pump your tank. A larger tank (1,000+ gallons) may take twice as long (40-60 minutes) to empty. How long it takes depends on the equipment used, how fast the technician works, and other factors (such as finding and uncovering the septic cap, inspecting and repairing any aging or malfunctioning parts). Here is what you should expect from a septic tank pump service:

Locating your tank

If your septic cap isn’t obvious, it might be buried. Your septic service might be able to find it by locating and following the sewer line. However, be prepared for them to ask for an as-built diagram, which you can get from your local county records office.

Digging up a buried septic cap

If your septic is buried, the septic service may have to dig it up. This is a good time to ask them to install a septic riser, which is a pipe that extends the cap to ground level for easy access.

Measuring solids

The septic technician will measure the level of sludge (the solids) at the bottom of the tank with a tube called a sludge judge. This measurement will tell the technician if your septic should be pumped. Accumulation changes over time depending on household size and how efficiently the septic is working. Septic services maintain a record of your sludge measurements, which can alert them to issues.

Removal of solids (and liquids)

The technician should scrape the bottom of the tank to ensure all the solids will be removed. They will then insert a hose to pump out the solids. Although the objective is removal of the solids to maximize your tank’s capacity, liquids must be removed to get to the solids.

Inspection

A good septic service will clean the filter at the same time your tank is pumped and inspect the system for any required maintenance.

Wastewater disposal

The septic service will remove the wastewater from your property and dispose of it in a sewage treatment plant, or it may be processed and used as fertilizer as your state and local laws allow or require (don’t shoot the messenger).

When a septic tank should NOT be pumped

If you’re selling your home, you should not have your tank pumped within 3-4 weeks prior to an inspection. This can prevent an effective test and may be considered an act of fraud. The septic inspector will have the tank pumped immediately before the inspection.

Where to find a reputable septic service to pump your tank

If you’re new to your home, services like Angi, HomeAdvisor, and HomeGuide can refer you to a reputable local septic service. However, your real estate agent, neighbors, friends, coworkers, or even a Google search can also point you in the right direction. Check reviews on Google, social media, and BBB to ensure the service you hire has a good reputation. Also, confirm that the service you choose has the required state and local licenses. It’s always a good idea to get bids from three different services and ask what is included with the service.

How septic system and tank condition affect resale value

As of 2015, there were 21 million rural homes on septic systems throughout the U.S. While some buyers may perceive a lower value, there is really no difference in value between a home with a good operating septic and a similar home on municipal sewer. A knowledgeable buyer will appreciate not paying municipal sewer fees. According to Van Camp, it’s the real estate agent’s job to educate buyers. That said, if your septic is failing or illegally installed, your state may require you to repair or replace the system before you sell.

Bottom line

If you live in a home with a septic system, maintain your tank by having it pumped every 3-5 years to keep it running smoothly, protect your family, and prevent costly damages to the tank as well as nasty backups in your home or yard. A well maintained tank will last 40 years or longer.