What is a characteristic of large diameter gravelless pipe (LDGP) systems?

Large diameter gravelless pipe (LDGP) systems are designed to utilize larger diameter perforated pipes—typically 8 or 10 inches—and do so without the need for gravel. This characteristic is significant because it allows for enhanced effluent distribution and improved site conditions, particularly in areas where traditional gravel systems may not be feasible due to site constraints. The absence of gravel not only reduces the volume of materials required for installation but also minimizes excavation and installation time.

Chambers are often used in certain types of systems for effluent distribution, but this option highlights the specific function of LDGP systems where gravel is omitted. The LDGP design supports more effective use of space in the leach field and can lead to more efficient treatment of wastewater.

In contrast, the other options do not align with the defining features of LDGP systems. Standard 4-inch pipes with gravel depict traditional septic system designs rather than the gravelless approach. The requirement for a secondary treatment facility, while sometimes necessary for specific sites or systems, is not inherently a characteristic of LDGP systems themselves. This understanding is crucial for professionals involved in septic system installation and maintenance.