What is the maximum trench length for gravelless systems?

The maximum trench length for gravelless systems is 100 feet. This specification is critical for ensuring that the system operates efficiently and effectively. In wastewater treatment and dispersal, maintaining a certain trench length helps to optimize the absorption and filtration processes of the effluent. A longer trench might lead to inadequate treatment or even system failure due to insufficient soil contact time or soil saturation, which could result in the effluent surfacing or contaminating groundwater.

By limiting the trench length to 100 feet, regulations ensure that the system remains within effective operational parameters, facilitating adequate percolation rates and promoting proper aeration and treatment of effluents. This length strikes a balance between the need for adequate surface area for treatment and the practical considerations of installation and maintenance.

This parameter is rooted in the engineering requirements for private sewage disposal systems, reflecting the importance of the soil's capacity to treat wastewater effectively before it reaches the groundwater.