Which of the following is a non-mechanical alternative to pumps in septic systems?

Siphons are indeed a non-mechanical alternative to pumps in septic systems. They operate based on the principle of gravity and hydrostatic pressure to move wastewater or effluent from one point to another without the need for electrical or mechanical components. This can be particularly advantageous in systems where power supply is unreliable or where operators seek to minimize mechanical failure points.

Siphons can create a difference in elevation between the source of the liquid and the discharge point, allowing the natural movement of fluids through a process known as siphoning. They can effectively transport effluent from a septic tank to a drain field or other treatment processes as long as the design is appropriately applied and the system is well-maintained.

In contrast, filters, valves, and compressors serve different functions within a septic system. Filters typically help in treating effluent by removing larger solids or particles, valves control the flow of liquids, and compressors are mechanical devices that provide air or pressure to facilitate certain biological processes. However, none of these options serve as an alternative method for fluid movement akin to how siphons function in septic systems.