Repair Options for Ailing Septic System

By Paul Bianchina

A septic system is one of those parts of the house that we take for granted. Drain the sink, flush the toilet, and as long as the water disappears we don't give it another thought.

Until it fails, and then we tend to not be able to think about very much else.

As long as you keep the septic tank pumped on a regular basis - typically every three or four years, unless you're a heavy water user - there's really not all that much that is going to go wrong with the tank itself. What can fail, however, is the drainfield. The drainfield is that system of perforated underground pipes that channels the effluent - the liquid discharge from the septic tank - out over a large area of the ground, where it then percolates slowly down through the soil to become naturally purified and rejoin the aquifer.

The drain pipes that make up the drainfield rest in rock-lined trenches, which are specially designed and installed to keep soil from clogging the perforations. Even the best-designed and installed system can still fail, however, for any one of a number of reasons:

• High seasonal groundwater, which can overwhelm the drainfield with moisture.
• Poor soils, such as clay or hardpan, where the soil's consistency is such that the effluent will not percolate through the soil at a rate equal to or greater than the rate at which it's produced.
• A lack of regular maintenance. If the tank is not pumped regularly, some of the solids that typically remain in the tank until removal can wash out into the drain field and build up silt, which then clogs the pipes and reduces the effluent flow until it backs up somewhere else.
• Household habits. This can include extremely high water use, which overwhelms the drainfield, or the regular introduction of excessive paper or fibrous food waste into the tank, which can flow into the drainfield and clog the pipes.

Drainfield Repair

Changing household habits and performing regular maintenance on the tank are the two best methods of preventative maintenance to keep your septic system healthy and happy. However, if your drainfield does fail at some point, you have a couple of options about how to deal with it.

First, you can dig up and repair or replace all or part of the existing drainfield. This is typically a viable solution if one or two of the lines have become clogged with silt or other material, but the trenches, soil, and drain rock in the field are otherwise in good condition. Many septic pumping and maintenance companies have small cameras that they can pass into the drainlines to examine their condition and help you decide if this is the best way to proceed.

Another option is to abandon part of the drainage system and basically start over. Every standard septic system, when first designed and approved by the municipality having jurisdiction over it, will have a tank, a drainfield, and a certain amount of additional land dedicated to it that is known as a reserve or a repair field. This additional allocation of land is there for the express purpose of having enough room for you to add a sufficient amount of new drain lines to get the system operating at full capacity again.

With advances in technology, there are now a couple of other potential solutions to drainfield failure that may keep you from having to dig up your entire yard, and may save you some money at the same time. The first is "jetting," a procedure that utilizes special pumps to inject high-pressure water into the drainlines to break up silt deposits and other solids, coupled with powerful vacuum lines that suck the broken-up solids out of the lines before they can settle again.

If the problem stems from poor or compacted soil, hope may come in the form of another new-technology solution known as "soil fracturing." Highly specialized equipment from companies such as Terralift utilizes a pneumatic hammer that is used to drive narrow probes down into the soil of the drainfield, typically to a depth of between 3 and 6 feet. Air is then forced into the soil at a carefully controlled rate, which fractures the hard soil and creates tiny channels through it. Next, polystyrene pellets are injected into the newly aerated soil, which keeps the passages open so the soil will not simply compact again.

If you encounter drainfield problems, contact an experienced, licensed septic maintenance company to discuss which of these options will work best for your particular system.

Copyright 2003-2006 Inman News.