When it’s time to install a septic system, its depth is one of the most crucial aspects. This not only determines how well each part works, but how well the parts work together. In other words, how deep your system is installed will influence its success.
However, if you’re like most homeowners, you likely want to keep the system hidden and out-of-sight. You might even be thinking of a deeper installation to ensure that the top of the tank is completely covered.
But a deeper placement could be difficult to access during routine pumpings. It could also prevent gravity from properly moving effluent into the drainfield.
And then there are the following factors, which affect how deep a septic system should be. Read on to learn about what to consider, along with the typical recommendations.
WHAT DETERMINES THE DEPTH OF YOUR SEPTIC SYSTEM?
When it’s time to bury your septic system, there are several factors to consider:
If you have a high water table, a deep septic installation may not be the best choice. You might need to add more soil to provide adequate absorption. This creates a mound that serves as an above-ground drainfield.
On a similar note, the contents of your soil also matter. High water tables are common in regions with high amounts of clay. A professional septic company—like Paradise Valley Septic—can determine your soil makeup during the planning process.
While planning and designing your system, your technician will analyze the physical features of your property. This may include slopes, nearby bodies of water and drainage patterns of the land. From there, they can determine the ideal trench depth of your drainfield.
Type of Tank
It’s also important to consider the type of tank that’s appropriate for your property. Many tanks are made to hold up to 2 to 3 feet of soil on top, so placing them any deeper might violate the manufacturer’s warranty.
HOW DEEP SHOULD MY SEPTIC SYSTEM BE?
Let’s look at the typical depths for each part of a septic system:
SEPTIC TANK: 4 INCHES TO 4 FEET DEEP
Depending on the above factors, your septic tank may be placed anywhere between this range. It’s also possible to install it at ground level, which makes it easy for technicians to access.
But what if you want to install your tank below ground level but still make service easy? You can install a septic tank riser, which brings the opening of your tank closer to the ground.
It’s best to avoid placing your septic tank deeper than necessary, though. If it’s installed too deep, effluent might backup instead of flowing into the drainfield.
DRAINFIELD: 2 TO 4 FEET DEEP
After effluent leaves the septic tank, it flows through perforated pipes in the drainfield. This area is typically 2 to 4 feet deep.
You don’t want to install your drainfield any deeper. The bacteria in the soil need enough oxygen to filter wastewater. If there’s too much soil, the friendly microorganisms won’t have an adequate oxygen supply—resulting in a dreaded septic backup.
Moreover, if you’re installing a gravity system, the drainfield will need to be deeper than the septic tank. This means your septic tank and drainfield can’t both be 4 feet deep. If this isn’t possible, you’ll need a pumped system.
LET PARADISE VALLEY SEPTIC FIGURE OUT THE DETAILS
As you can see, there isn’t a one-size-fits-all answer. Our team at Paradise Valley Septic can determine how deep your septic system should be. While we’re at it, we can also help you choose the best type of septic system for your property.