As septic pumpers, one of the questions we get asked is, “How do I know what size my septic tank is?” The price of having a tank pumped is based on its size, the lid accessibility, and the home’s location. Below are three common ways to calculate the septic tank’s size.
#1 Rule to find tank size
Here in Michigan, we follow a simple rule of thumb. If a house has 3 or fewer bedrooms, the tank is 1,000 gallons. If a house has 4 or more bedrooms and the system is up to code, the tank is likely 1,500 or even 2,000 gallons. Intuitively, it is easy to think that the tank size is based on the number of bathrooms. However, septic system size is based on bedrooms to estimate the total number of persons using water. For instance, a house could have 100 bathrooms, but if there are only 2 bedrooms, it’s unlikely that more than 4 people will live there. However, if a house has 10 bedrooms, there will be much more flow, even if there is only 1 bathroom, due to the increased occupancy. More people, bigger tank.
Health department records
Another way to find the tank size is to contact the local county health department. If the septic system was installed around 1990 or later, the health department will likely have records of the tank size. The older the system, the less likely the department will have records on file, but it is worth checking.
Pumper records
The third way is to obtain an invoice from when the tank was last pumped. On our septic trucks, a meter shows the total gallon amount. After each job, the driver checks this meter to determine the size of the tank. If the tank has been pumped recently, the size should be recorded on the invoice, or the pumper will have records of how large the tank was.
When in doubt, pump it out
Pumping your septic tank keeps the solid buildup of grease and sludge at a healthy level and prevents drain field failure. If the tank has not been pumped in the last three years, it is time to have it done! If you have questions about your system or need service, book with us online or give us a call!
