Septic tanks are common for homes in rural areas and homes not connected to the city or municipal’s sewer system. It is not uncommon for a new homeowner to find the property has a septic system, yet they are unfamiliar with how it functions. One of the most common questions for such homeowners is, “How often should I pump the septic tank?”

How Does a Septic Tank Work?


To understand how often you should do septic pumping, among other basic septic tank maintenance steps, you need to know how a septic tank functions. A septic tank helps households manage wastewater or drain waste in a natural and environmentally friendly manner. Typically, wastewater from the kitchen, bathroom, toilet, and laundry room leaves the house and enters the septic tank.

The wastewater naturally separates into solids, liquid waste, and scum. The solids or sludge settle at the bottom of the tank since they are heavier, while the scum, usually consisting of oils, grease, and soap, settles at the top. The watery mix or effluent settles in the middle of the tank, where there are perforated pipes to a drain field.

Upon getting into the drain field, the soils and other elements filtrate and purify the effluent back to groundwater. A septic system also allows bacteria and other microorganisms to consume and dissolve the sludge or solid waste that settles at the bottom of the tank. However, over time and with increased usage, the sludge might be too much for the microorganisms to consume or dissolve.

The undissolved sludge eventually leads to an overflow or sewage back-up if there is no regular septic maintenance. Besides undissolved sludge rising to dangerous levels, the scum may also get abnormally thicker, causing similar problems. While several factors determine how often you should pump your septic tank, septic tank experts recommend septic pumping every 3 to 5 years.

Some of the factors or primary considerations that can determine how often you should pump your septic tank include:

  1. Household size. The size of your house and the number of people living there determine how often you need septic tank pumping. Typically, the more people there are in your home, the more drain waste your household produces. Essentially, your home’s size determines your septic tank’s size. While you can always replace your septic tank as your household expands, some states, cities, and local jurisdictions may have minimum septic tank size requirements regardless of your household size.
  2. The size of your septic tank. Closely related to the size of your home is the size of your septic tank. How often a septic tank needs pumping depends on how fast it fills up; hence its size is a great determiner. For instance, a septic tank with a volume capacity of 1,000 gallons serving a four-member household will fill up faster than a 1,500-gallon-sized tank serving a similar family size. A septic tank professional can always help if you are unsure about the size of your tank and will recommend how often you need septic pumping based on the size.
  • Amount of wastewater generated. Despite similar sizes, some families produce larger volumes of wastewater than others, depending on their unique household activities. Some factors like using a garbage disposal system can significantly increase a household’s wastewater. Other factors that affect the amount of wastewater your household generates include how regularly you use the laundry machine and the types of soaps or chemicals used in your home. The large volumes of wastewater might necessitate you to pump your septic tank frequently compared to your neighbors with similar-sized families and septic tanks.
  1. The volume of solids in your drain waste. Like the amount of wastewater a household produces, the volume of solids in the drain waste can determine how often you need to pump your septic tank. Since septic pumping is mainly done to remove solid waste, the volume of solids your household generates affect pumping frequency. For instance, having a garbage disposal system might mean you produce significantly above-average solids, hence the need for frequent septic pumping.

While there are industry recommendations on how often to pump your septic tank, pumping should be done as needed. No matter how often you require septic pumping, you can always rely on pumping and cleaning services from Curtis Plumbing. We serve the Tucson area in Arizona and are committed to professionally taking care of all your septic system needs. Contact us today to book an appointment and learn more about our services.