Which method is commonly used to determine soil percolation rates?

The commonly used method to determine soil percolation rates is conducting a percolation test, often referred to as a "perc test." This test involves digging a hole in the soil, filling it with water, and measuring how quickly the water drains or percolates through the soil. By assessing the rate at which water moves downward, the percolation test provides critical data necessary for designing an appropriate on-site sewage facility, as it indicates how well the soil can absorb and filter wastewater.

The percolation rate is essential for ensuring that the sewage system will function effectively and prevent problems such as surface water contamination or system failure. Other methods, such as using a soil moisture meter, visual inspection of soil layers, or observing vegetation growth, do not provide the specific percolation rate needed for such assessments. While these methods may offer some insights into soil conditions, they lack the precision and direct measurement characteristic of a percolation test, making the "perc test" the standard approach for this evaluation.