What are the Dimensions of a 1500 Gallon Septic Tank?

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What are the Dimensions of a 1500 Gallon Septic Tank?

Knowing the dimensions of a 1500-gallon septic tank is quite significant for a number of reasons. These dimensions determine the actual size of the tank or its holding capacity. The dimensions are determined by expert contractors, after considering various factors. In this article, we will discuss how dimensions of the septic tank are important, and more such related facts.

So, what are the dimensions of a 1500 Gallon septic tank? A 1500-gallon concrete septic tank generally measures 145 inches (L) X 78 inches (W) X 61 inches (H). However, there can be slight variations in the dimensions due to the thickness of the construction material used.

Keep reading to know more about what influences the dimensions of septic tanks and why it is necessary to use a tank of the right size.

1500 gallon septic tank typical arrangement drawing for inspection article
1500 gallon tank sketch

Determining the Size and dimensions of the Septic Tank

The size of the septic tank determines its dimensions. The required size of the septic tank is calculated by experts, after considering facts like the size of the house and members living in the property. Thus, it is important to take time to calculate the correct size of the septic tank.

The size and dimensions of a septic tank are generally based on the total number of bedrooms, the occupants of the house, and the fixtures which the septic system shall service.

Steps To Calculate The Size of Septic Tank

Step 1 – This is the first step when you will calculate the total occupants who will use the septic system. In most of the municipalities, it is assumed that any two-bedroom house will have 4 occupants. Any 3-bedroom house generally has 6 occupants.

Step 2 – You can count the total bathrooms which the tank shall service. If there is just one bathroom, but you feel you might add another bathroom, you should ideally count the second bathroom when you are calculating the bathroom.

Step 3 – You can count the total number of fixtures in your property. These plumbing fixtures will include clothes washer, dishwasher, showers, toilets, and taps. You can count any other fixture which will drain in the septic tank.

Step 4 – You can also take calculations to the local permit office. You can check them against the different local regulations. You can determine the size of tank. Sizing rules also keep changing from one location to another.

Septic Tank Types – On the Basis of Material Used

Those who need to have a septic installed can select between three main kinds of tanks. The choice of tank depends on the homeowner or the local rules and regulations.

Here are the common kinds of septic tanks.

These are:

  • Concrete Tanks
  • Plastic or Polyethylene tanks
  • Fiberglass Tanks

Thus, a septic tank which has a capacity of 1500 gallon can have variations in its dimensions. This variation can be due to the type of material, contractor charges,

A septic tank with a capacity of 1000 Gallon might have slight variations in dimensions, depending on the kind of tank (whether it is a fiberglass tank, plastic tank or concrete tank).

Thus, a little understanding of the kind of septic tank is important so that you can understand the dimension factors. Knowing the dimensions of a septic tank is necessary, especially when there is a requirement for pumping or repairs by professionals.

Facts Related to Dimensions of a Septic Tank:

The table below is a brief of the dimensions of a septic tank. This is just an approximate and figures might change according to specific requirements of a property.

Type of TankTank CapacityTank Length (inches)Tank Width (inches)Tank Height (inches)
Concrete Septic Tank1500 Gallon1457861
Plastic or Fibreglass Septic Tank1500 Gallon1916051
Steel Septic Tank1500 Gallon5858144

** Read: Dimensions of a 1000 Gallon Septic Tank

What Happens if The Dimensions of The Septic Tank Go Wrong?

If the septic tank is not of the correct size, different types of problems will arise, and it will not be able to move the sewage away as expected. The health of the residents might be compromised if the dimensions are not correct.

If the Size of the Septic Tank is Small:

If the septic tank is not of the correct size, the homeowner shall face different types of problems.

  • The tank will fill up too soon. It will have to be pumped in a short duration.
  • There can be problems related to frequent clogging.
  • It might have to be pumped every time after a party or a large gathering.
  • If the tank is not pumped in time, there will be sewage backing up.
  • There can be problems related to overflowing sewage.
  • There will be constant problems of stench in and around the septic tank.
  • The tank might not function as per expectation. It might need frequent repairs.

If the Size of the Septic Tank is Too Big

Just as a small size septic tank causes innumerable problems, a large size tank is no good either. The tank needs a lot of time to fill up before it can have the bacteria build-up. This build-up of bacteria is extremely essential for further processing of the sewage.

In such a situation there will not be a proper breakdown of solids in the septic tank. As a result, the septic tank shall not function properly. Homeowners shall face various kinds of problems and money will be frequently spent on repairs & maintenance.

 Questions Related to The Dimensions of a 1500 Gallon Septic Tank?

  • How many bedrooms can a septic tank of 1500 gallon support?

A septic tank with 1500-gallon capacity is suitable for a house that has 5 bedrooms.

  • What is the ideal weight of a concrete septic tank with a capacity of 1500 gallon?

Any 1500-gallon concrete septic tank weighs around 12,500 lbs. The weight tends to vary depending on the wall thickness, top thickness, rebar reinforcement, and its specific dimensions.

  • Can I drive over a 1500-gallon septic tank?

No, it is never recommended to drive over a 1500-gallon septic tank. Driving over the septic tank shall harm the leach field. Besides, it might have a negative effect on the effectiveness of the tank.

  • How much time does a 1500-gallon septic tank take to fill up?

It might take years for a septic tank of 1500 gallon capacity to fill up. However, it is recommended to schedule an inspection every 3-5 years.

  • How much will it cost to build a septic tank of 1500 gallon?

The average cost of building a concrete septic tank can range between $1000 – $1,375. However, it can vary from one place to another and between contractors.

  • What happens if the septic tank is not pumped as per schedule?

If your septic tank is not pumped as per schedule, the solids will tend to build up in the tank. The holding capacity of this tank shall be diminished. Such solids might reach the pipe which feeds the drain. If this happens, there will be a clog. The wastewater might frequently back up.

Though a 1500-gallon septic tank is suitable for a house with 5 bedrooms, it is necessary to consider facts like how many people live in such a house. If guests are popping in now and then, it should be taken into account when determining the size of the tank.