How Your Septic Distribution Box Works

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What’s the D box of a septic tank?

In this article, we will learn how a septic distribution box works. We will also discuss the parts of the distribution box and their functions. A septic distribution box, also known as a D-box or splitter box, is a crucial component of a septic system. It is typically a rectangular box made of concrete, plastic, or fiberglass and is installed between the septic tank and the drain field. The purpose of a septic distribution box is to distribute the effluent (wastewater) evenly to the drain field, ensuring proper treatment of the wastewater and preventing any potential damage to the system.

The distribution box has an inlet or intake pipe that receives effluent from the tank and several outlet holes to discharge or disperse the effluent into the drain field lines. Gravity moves effluent from the tank to the distribution box, which is located downhill or at a lower elevation. Concrete distribution boxes are more durable and sturdier than the plastic ones and can last for over 30 years. Their size and shape varies depending on the type of septic system.
Most distribution boxes have a rotating flow-leveling device to ensure an even effluent distribution throughout the drain field. If a distribution box unevenly disperses effluent, the effluent will accumulate in one portion of the drain field and overwhelm it. That portion of the drain field will not be able to efficiently treat effluent. This leads to contamination of ground water. A malfunctioning distribution box or one that has been battered down by time, weather elements such as flooding and winter frost, needs to be urgently replaced in order to prevent a drain field failure.

How Do I Find My Septic Tank Distribution Box?

Unlike the tank, a distribution box does not need to be pumped out. However, it is important to inspect it in order to avoid costly repairs. HOW DO I FIND MY SEPTIC TANK DISTRIBUTION BOX?

  • You can easily locate your distribution box by looking for a depression in the area between the tank and the drain field. Another way to locate the distribution box is to follow the parallel depression lines that are usually 3 to 5 feet apart until you locate the box.
  • Your septic tank site plan will show or indicate the distribution box’s location. What is a septic site plan? A septic site plan is a drawing that shows the location of the septic tank, drain field, and other features. If you have lost your site plan you can request a copy from your local county authorities.
  • A plumber or septic tank specialist can easily locate the location of your distribution box using specialized tools.

How Your Septic Distribution Box Works: Problems

While a septic distribution box is a simple and effective way to distribute effluent, it can also be prone to problems. Some of the most common problems are:

  1. Clogging. Over time, solids and other debris can build up in the septic distribution box, preventing the flow of wastewater. This can lead to backups and overflows, causing damage to the septic system and potentially even the surrounding environment. Tree roots and non-biodegradable household products such as flushable wipes, cotton balls, condoms, feminine hygiene products, and grease can clog septic distribution boxes.
  2. You should ensure that the distribution box is level and does not tilt or slant in any way. This helps prevent uneven distribution of effluent into the drain field or leach field. Adjust your outlet holes to regulate the discharge of effluent depending on the amount of waste water your household produces.
  3. There are a few ways that weather can cause problems for a septic distribution box. For example, heavy rainfall can cause the septic tank distribution box to become inundated with water, which can prevent it from functioning properly. This can cause waste to back up into the house, leading to potential health and sanitation issues. Additionally, extreme cold weather can cause ice blockages in the pipes leading to and from the distribution box. Cold weather can also cause the distribution box to crack.

To prevent these problems, it is important to regularly inspect and maintain your septic distribution box. This includes having a professional check for clogs and damage, and performing necessary repairs or replacements.

Tell-tale Signs Of Malfunctioning Distribution Box

If you suspect that your distribution box is not functioning properly, it is important to contact a septic tank specialist for an inspection and repairs. Ignoring a malfunctioning distribution box can cause damage to your septic system and the surrounding environment.

Some common symptoms of a malfunctioning distribution box include:

If you notice any of these symptoms, it is important to contact a septic tank specialist for an inspection. They can diagnose the problem and recommend the necessary repairs.

Related Questions

It is also important to note that a septic distribution box serves as a crucial component in the distribution of wastewater throughout the septic system. Without a functioning distribution box, the septic system will not be able to properly treat and disperse the wastewater, leading to potential health and environmental hazards. This FAQ addresses some of the most common questions about how your septic distribution box works and how to maintain it so that you don’t have to worry about any clogs:

How close to the septic tank is the distribution box?

The exact distance between the septic tank and the distribution box varies depending on the layout and location of the leach field.

Do All Septic Systems have a Distribution Box?

Not all septic systems have a distribution box. In some cases, smaller capacity septic tanks may be connected directly to the drainage field without the need for a distribution box. The use of a distribution box is typically required in septic systems that have a larger volume of waste water, or in systems where effluent is discharged via multiple pipes. It is important to consult with a qualified septic system professional to determine whether your septic system requires a distribution box.

How long does a septic distribution box last?

The lifespan of a septic distribution box can vary depending on a number of factors, including the materials it is made of, the quality of its construction, and how well it is maintained. On average, a septic distribution box can last for 20-30 years with proper maintenance. However, it is important to note that certain factors, such as heavy use or extreme weather conditions, can shorten the lifespan of a distribution box. In order to ensure that your septic distribution box lasts as long as possible, it is important to have it inspected and maintained by a qualified septic system professional on a regular basis.

How deep is the distribution box?

Typically, most people bury septic distribution boxes underground at a depth of at least 2 to 4 feet. In some cases, the depth of the distribution box may be deeper, depending on the specific requirements of the septic system.

Does a septic distribution box have a lid?

Yes, most septic tank distribution boxes have a lid. Typically, a lid is located on top of the distribution box. People use it to access the inside of the box for inspection and maintenance purposes. The lid is made of durable material, such as concrete or plastic, and is securely attached to the distribution box to prevent unauthorized access.

Final Thoughts

In conclusion, the septic distribution box is an important component of a septic system. It helps to distribute waste water evenly across the drainage field, ensuring that it is properly treated and does not cause any issues. Overall, understanding how your septic distribution box works and being aware of potential problems can help you to properly maintain and protect your septic system. This will ensure that it continues to function properly and effectively treat wastewater, protecting your home and the surrounding environment.