What is the required fall of the pipe leading into a septic tank and to the drain field?

The required fall of the pipe leading into a septic tank and to the drain field is 1/4 inch per foot. This slope is necessary to facilitate proper flow of wastewater by ensuring gravity assists in moving the effluent through the piping system. If the slope is too shallow, it could lead to stagnation and cause solids to settle in the pipes, which may result in clogs or backups. On the other hand, if the slope is too steep, it can lead to excessive velocity, which may erode the pipe or lead to incomplete drainage.

In terms of practical application, maintaining a consistent slope of 1/4 inch per foot helps ensure that solids are adequately carried with the flow into the septic tank for effective treatment, while also allowing for a reliable transfer to the drain field. This is critical for the overall function and longevity of the septic system, ensuring that effluent is dispersed appropriately in the leach field, which is vital for groundwater protection and environmental health.