A perk test determines the water solubility level of a given piece of property. That is, whether or not the soil can take water. For example, properties in a high water area or a marsh land usually will not perk because the water table is too high, and the soil pores have reach their solubility level (cannot absorb more fluid).

A perk test is required to be performed on your property prior to septic installation and/or repair to ensure that the water level is low enough that the soil on the property can handle fluid without failing. In an area where the water table is very high, and the soil is unable to absorb fluid placing a system in this environment would cause failure as there is no where for the fluid to go that is leaving the system. In many cases, where this is true an 'engineered field' can be use, but this is not always the case. Final determination is made by the Health Department.