If you are planning to install a new septic system in your yard, you may be wondering what size tank you should purchase. Selecting the right size septic tank for your property is essential for avoiding frequent pumpings, costly repairs, and wastewater backups. While there are some basic guidelines to consider, the decision should ultimately be based on a variety of factors, including water usage, the size of your home, and government regulations.
Why Tank Size is Important
When it comes to septic tanks, size does matter. Typically, the biggest concern is with a septic tank that is too small for the household’s usage. When a tank is too small, it will fill up much quicker, requiring more frequent pumpings to maintain appropriate levels. In this scenario, the bacteria inside the tank won’t have enough time to break down the wastewater inside, including fats, oils, and greases (or FOG). If the solid waste makes it to the outflow pipe and eventually the drain field, it could create a clog or cause damage to the system. In addition, as the tank quickly fills with wastewater, some of it could begin to back up into your home’s drains and toilets.
Many homeowners decide to solve this problem by purchasing a much larger tank. While it’s certainly better to have a little more room in the tank, installing a tank that is too large could result in issues as well. Without enough wastewater cycling through the tank, the liquid inside the tank, or effluent, may not empty properly into the drain field. In addition, there may also not be enough bacteria produced inside the tank to break down the solid waste.
Basic Guidelines
You should consider a variety of factors to determine the right size tank for your home, and it’s important to have a consultation with a septic specialist before making any purchasing decisions. However, there are some industry standards to get you started:
- 750 gallon tank—1-2 bedroom home, less than 1,500 sq. ft.
- 1,000 gallon tank—3 bedroom home, less than 2,500 sq. ft.
- 1,250 gallon tank—4 bedroom home, less than 3,500 sq. ft.
Factors that Determine the Right Size Tank for Your Home
Water Usage
While each of the following factors is important to consider, the most effective way to determine the size of your septic tank is to calculate the amount of water your household uses. That’s because there is a maximum capacity inside the tank before the wastewater can make its way to the leach field. If your family tends to produce more wastewater than average, it may make sense to install a slightly larger tank than guidelines suggest.
Property Size
Some homeowners installing septic tanks may be limited by the size of their property. Consider where you’ll be placing your tank and leach field. Keep in mind that local government regulations may dictate a specific distance between your septic system and your property line. While you should certainly still install a septic tank that will hold the proper volume for your household’s water usage, you may not have room for a substantially larger tank.
Number of Bedrooms and Occupants
According to the United States Geological Survey, the average American uses 80-100 gallons of water a day, and the more people that live in a home, the more wastewater is produced on a daily basis. That’s why the number of bedrooms in your home should be taken into account when selecting your septic system. If the tank is too small to hold the wastewater used by your family, it could begin to back up into your home’s sinks, toilets, and showers.
Government Regulations
Regardless of what size tank you think is best, it’s important to check your local government’s regulations. Each locality sets codes based on things like soil quality and the water table, so even if you’ve installed a septic tank in another home recently, the guidelines could be different. These regulations will also determine where you can install the tank and leach field on your property. Failing to follow these regulations could result in fines and additional costs to relocate your septic system.
The Importance of Regular Maintenance
Once you’ve selected and installed the right septic tank for your needs, it’s important to set up a regular maintenance schedule. While selecting a smaller tank could require you to pump your tank more frequently, every tank should be pumped periodically, regardless of size. Typically, you can expect to have your septic tank pumped every three to five years.
In addition to scheduling regular pumpings, you may also want to consider adding a bacteria-based product monthly. When the bacteria are introduced to the septic tank, they get to work immediately to completely digest fats, oils, and greases inside the tank. This could not only reduce the frequency of your pumpings, but the likelihood of clogs and damage to your leach field, as well.
Selecting the Right Size Septic Tank for Your Property
Septic tanks are not a one-size-fits-all solution. In fact, many factors should be considered when determining what size septic tank you need, including the amount of water your household uses, along with the size of your home and property. Be sure to consult local regulations, as well, to ensure that your tank meets government guidelines. Once your septic system is installed, schedule regular pumpings and use a bacteria-based product monthly to keep your system running effectively for years to come.