Compare Aerobic vs Anaerobic Septic System Costs
Aerobic vs Anaerobic Septic System Average Prices & Buying Guide
No, we’re not talking about your gym routine. Like exercise, septic systems can be aerobic or anaerobic. And if you’re in the market for a new septic system, it’s important to understand the difference between the two.
Aerobic septic systems contain a mechanism that anaerobic systems do not: an aerator that injects oxygen into the tank from outside. This allows for aerobic bacteria decomposition, which is cleaner, faster and more efficient.
So why doesn’t everyone have an aerobic septic system? Well, they’re more expensive and more complicated to install and maintain. Until recently, they were reserved mostly for municipal sewage treatment plants and rarely used for residential properties.
Anaerobic septic systems are the more traditional and affordable choice for residential properties. They do not have an aerator that injects oxygen into the septic tank, so they rely solely on bacteria that can live without oxygen.
Pros and Cons of Aerobic Systems
Aerobic systems require smaller drain or leach fields, making them a great option for small lots, and they typically have alarms that alert homeowners to problems with the system, saving time and hassle down the road. They’re better for the environment because waste is processed faster. As we’ve mentioned, they’re cleaner, faster and more efficient.
On the downside, aerobic systems are more likely to become clogged, and they can fail during power outages because they require electricity. Aerobic systems require more frequent and costly maintenance, and the effectiveness of these systems can be dramatically reduced with neglect (failing to keep up with regular service visits) or if certain harsh chemicals are poured down the drain. In some cities or towns, aerobic systems are not allowed - so check with local officials.
Pros and Cons of Anaerobic Systems
With anaerobic systems, price and availability are the primary benefits. The systems are less expensive and more readily available than aerobic systems. Most contractors are more familiar with how to install them. They require less maintenance, too.
However, anaerobic systems are dirtier, less efficient and take up more space. The wastewater they produce is more harmful to the environment. Anaerobic systems often produce a rotten egg smell, and the gases they create can deteriorate your septic tank more quickly.
Cost of Aerobic Septic Systems
Aerobic systems start at about $6,000 and range upwards of $15,000. The price varies based on your region of the country, soil conditions, the size of the septic system and the amount of local competition for septic work.
Site evaluations, which are typically required in order to install any type of septic system, run $200 to $400. Local permits usually fall in the same range. Professional pumping and inspection, required every one to three years for all septic systems, usually cost a couple hundred dollars each.
Specific to aerobic systems, you can expect an increase in your monthly electric bill. Also, parts such as the motor and timer will fail from time to time. A replacement motor might cost $500 to $600, while timers are usually less than $100.
Cost of Anaerobic Septic Systems
Anaerobic systems start at about $3,000 and usually cap out at about $12,000, depending on the same variables mentioned above. As with aerobic systems, you should budget for the cost of a site evaluation, permits, and occasional pumping and inspection.
Choosing a Septic System
The choice between aerobic and anaerobic septic systems usually comes down to personal preference. Ask yourself these questions:
- What is my budget? - If you’re on a very limited budget, you’re probably better off going with a traditional anaerobic system.
- What size is my lot? - For very small lots, you might have to shell out the extra money for an aerobic system.
- How important is environmental impact? - If you’re someone who cares deeply about the environment, an aerobic system might be worth the extra cost because the wastewater it produces is much cleaner. If the environment is not a big priority for you, an anaerobic system might be your preference.
- What are the local laws? - Does your city or town prohibit aerobic systems for residential properties? If so, the choice has been made for you.
- Am I good at sticking to a maintenance schedule? - Aerobic systems may be more efficient and longer lasting, but those benefits can disappear if you don’t stick to a regular maintenance schedule. Aerobic systems require more attention than anaerobic systems, so think twice if you’re the type of person who forgets to get an oil change or make a dentist appointment on schedule.
Choosing a Contractor
A quick Google search should turn up plenty of septic contractors in your area. But not all are alike - you shouldn’t just pick one at random. Here are some tips:
- Ask for references. If you have a septic system, chances are your neighbors do too. Find out who they used and if they were pleased with the service. Or, you can consult your local wastewater management office or similar entity.
- Seek quotes from multiple contractors to compare prices, but don’t choose on price alone. Throw out any quotes that seem suspiciously high - or low.
- Make sure any company you hire is licensed, bonded and insured. Ask for proof. If a company is bonded and never completes the job, you can make a claim against the bond to recover the money you’ve spent or have someone else finish the job for no additional fee. Insurance is important because otherwise you could be financially liable for accidents that occur on your property.