If you’re ready to install a new septic system, it’s important to work with an experienced septic provider. A qualified technician can help you properly design your new tank, which will ultimately determine its efficiency and longevity. But what does septic tank design involve, anyway? Here are some of the most important aspects:



One of the most important factors is the size of your household. That’s because the number of bedrooms will determine how much water is used each day, and therefore, how big your tank needs to be.

Generally, a septic tank is made to receive approximately 120 gallons per bedroom per day. This number is based on the fact that an individual uses approximately 60 gallons of water each day — and that there are two people in every bedroom. Appliances like dishwashers or washing machines should also be taken into consideration.

Residential tanks can usually handle 750 to 1,250 gallons. However, other factors (like local government regulations and your climate) may also affect tank size.



Septic tanks are typically rectangular. Additionally, most tanks measure approximately:

  • 4.5 feet wide
  • 8 feet long
  • 6 feet tall

The exact dimensions of your tank will depend on its size.

As for how deep septic tanks should be buried? Depending on your water table, soil, and type of tank, your tank may be anywhere from 4 inches to 4 feet deep. A majority of tanks are designed to handle no more than 2 to 3 feet of soil on top.



The material of a septic tank needs to be watertight. Otherwise, wastewater will seep out and taint the surrounding environment.

Common materials used for septic tanks include:

  • Concrete
  • Fiberglass
  • Fiber-reinforced plastic
  • High-density plastic

The best choice depends on your landscape, as well as the type of septic system.

It’s worth noting that plastic septic tanks are cheaper and lighter than other options. But due to their light weight, they’re more likely to move around.

Back in the day, some septic tanks were made of steel — but this material is no longer recommended. Here’s why: Steel typically begins to rust after 20 to 25 years, leading to corrosion and structural damage. If this occurs on the top of the tank, it can be unsafe for people and animals on the ground over it. Likewise, if the bottom becomes corroded, sludge could leak out and contaminate the drainfield.



Septic tank design should always be done by a professional — and Paradise Valley Septic is here to help. Our experienced technicians can create a tank and drainfield that suits your household size, while considering any local regulations and requirements.

And when it’s time for a routine pumping? We offer residential pumping services too. To learn more, contact us online or call us at 480-607-7763.