A distribution box is an essential component of a drainage field or septic system. It serves as a junction point that evenly distributes wastewater or effluent from the septic tank into the individual drain lines or trenches within the drainage field.


Here are the main reasons why a distribution box is necessary:

  1. Equal distribution: The primary purpose of a distribution box is to ensure equal distribution of wastewater to all drain lines or trenches in the drainage field. Without a distribution box, there may be an imbalance in the flow of wastewater, leading to some drain lines being overloaded while others receive insufficient amounts. This can result in uneven drainage, poor treatment of the wastewater, and potential system failure.
  2. Hydraulic balance: The distribution box helps maintain hydraulic balance within the drainage field. By distributing the wastewater evenly, it prevents excessive pressure or flow on any particular drain line, preventing overloading and potential damage to the system.
  3. Effluent quality: A distribution box plays a crucial role in promoting effective treatment of wastewater within the drainage field. By uniformly distributing effluent across the drain lines, it allows for better contact between the wastewater and the surrounding soil. This enhances the natural biological processes that treat the wastewater by filtering out contaminants and facilitating the breakdown of organic matter.
  4. Maintenance and accessibility: The distribution box provides a central access point for inspection, maintenance, and potential repairs of the drainage field. It allows for easy monitoring of the system's performance, including checking the flow rates and identifying any issues with individual drain lines. If a particular drain line becomes clogged or damaged, it can be isolated and repaired without affecting the rest of the system.


In summary, a distribution box is crucial for ensuring even distribution of wastewater, maintaining hydraulic balance, promoting effective treatment of effluent, and providing accessibility for maintenance and repairs within a drainage field or septic system.