Hydraulic Load Tests

Soil Absorption Systems (SAS) absorb sewage effluent. It is what keeps and onsite sewage disposal system (OSDS) “onsite”. This means that when a toilet is flushed in a house connected to an OSDS, the sewage is pretreated and released right in the ground, on the same property. There is no city sewer pipe or other way for the sewage to disperse. It all happens right there, in the yard.


As soil absorption systems (i.e. drainfields, drywells) age, they absorb less and less effluent over time. It is important, especially upon real estate transactions, that a hydraulic load test is conducted to determine the system’s capability to absorb and disperse of wastewater. This is done by running water through the home’s plumbing or outside with water brought onsite. Water is run through the septic system to ensure alright flow and absorbability. You do not want to see the water level rise. This indicates a problem and often means a back-up in the house!


Every SAS has a lifespan. Every lifespan is different for every system. The only way to judge the status of a soil absorption system is to test it; you cannot simply look and know the issue. Hydraulic load tests are a critical component to every septic inspection. Problems that can be exposed by conducting a hydraulic test otherwise be hidden and remain unfound.