Utah's Premier Company for Complete Wastewater Treatment Systems
BUYING A LOT?
Before you call to schedule your perc test,
for things you'll need to know.
PERC TESTING
AOS has conducted thousands of perc tests over the years. We know soils, and always ensure that they’re yielding the anticipated results. Due to their importance in the septic system design and installation process, every perc test is conducted by AOS owner Ben Witt. In the state of Utah, the standard to get certified for perc testing is low, so it's critical that you schedule a perc test with experienced experts.
A percolation test, commonly abbreviated to perc test, determines the soil on a property’s ability to absorb water. Before conducting a perc test, we make sure that every lot is a candidate for one. We will look at slope, lot sizing, proximity to open water, setbacks, and known problems in the area. It's likely we've done perc tests on neighboring lots and can tell you a whole lot about the nature of the soil in the area.
A hole is opened up in the soil, and water is placed in the hole for several hours to see how much water the soil can take over a given period of time. This test typically takes two days, but the duration can vary based on the soil’s drainage properties.
Most soils in Northern Utah will be suitable for some type of septic system. Soils with faster drainage properties, like sandy soils, or those that don’t drain water at all, such as clay soils, may require an alternative system.
The perc test is the basis for the entire septic design. A test conducted improperly can result in an undersized system, which will fail prematurely, or an oversized system that can cost thousands in unnecessary expenses.
There's no point in a perc test if a lot is too steep or has other prohibiting factors.
Before scheduling your perc test, find out if your lot has:
SPACE
Generally, one acre of usable space is sufficient to have a home, driveway, and septic system, including the replacement area. Lots smaller than one acre use septic systems all the time, but may require extra planning and design considerations. Lots with extremely limited space should be inspected prior to a perc test to ensure the area is sufficient.
OPEN WATER
There are open water setback requirements for any septic system. For a conventional septic system, the setback is 100’. For alternative septic systems, the setback is 50’. Riverfront properties or properties with streams sometimes have a limited area where a septic system can be placed. Any native feature on the property that can have water flowing through it, even if it is just a few days a year, will have a setback from it.
GROUND WATER
If your property is in an area with known groundwater issues, this may be the determining factor as to whether or not the lot will be deemed buildable. Water monitoring is required during the high water season (usually sometime between March and August). During a drought year, which is increasingly common, water monitoring may be required for up to two years.
BEDROCK
If a lot has bedrock, it can make the property difficult to build on, if not entirely unbuildable. If a lot has rock outcroppings on it, large boulders at the surface (1’ diameter
or larger) or is in an area that has known bedrock issues, this must be further analyzed before scheduling a perc test.
SLOPE
Most of the time, if a lot’s slope is 25% or less, it will be suitable for a septic system.
If your lot has slopes of 26% - 35%, it can still be considered for a septic system with a slope stability study. These can be fairly expensive and time-consuming, as well as difficult to coordinate with real estate transactions, so budget additional time and money for septic approval.
If your lot has slopes over 35%, there will be setback issues. There are regulations against unstable slopes (hillsides), in addition to concern of septic effluent daylighting. If the lot has no areas with slopes under 35%, it will most likely be unbuildable, though there may be limited options to explore.
When planning a perc test for a septic drain field, an ideal lot is a large, flat area with deep topsoil and no open or ground water present. If that sounds like your lot, it’s likely ready for a perc test. Click here to schedule your test with AOS or fill out the form below.
If your lot doesn't meet these criteria, give us a call. As our name suggests, we offer alternative solutions for challenging lots that may fit your needs. Check out our page for alternative systems here to learn more.