There is no way to guarantee that a drainfield will never fail even under the best of conditions. There are many factors which determine the water absorption capabilities of a drainfield. The most common causes of drainfield failure are 1) hydraulic overloading, i.e. too much water for the ability of the soil system to absorb in a timely manner, 2) excessive biomat formation, i.e. too much waste passing to the drainfield which decreases the amount of oxygen available and leads to anaerobic conditions, 3) poor site evaluation and system design or installation, 4) compaction of the soil in the drainfield during installation or afterwards. This can be caused by driving over the drainfield or covering it with other materials such as pavement, 5) soil-mineral bonding, i.e. this is probably more important in high clay soils. (Small Flows, vol 13, No 2, 1999).
Good water management practices can help prevent hydraulic overloading. Repairing all leaking faucets and toilets immediately and spreading the use of water over the entire day can help prevent this.
Excessive biomat formation can be minimized by ensuring that the septic tank is pumped on a regular basis and controlling the amount of organic materials added to the system. These include not only grease and oils, but also food by-products, shampoos, cream rinses, and nonbiodegradable products.
Although many of these types of materials are biodegradable, they all contribute to sulfide formation and thus excessive biomat formation and soil clogging.
Preventative maintenance treatments with Septic-Scrub can help control and minimize the effects of these problem areas. If the system is in good operating condition and the septic tank is pumped on a regular basis, then a once or twice a year preventative maintenance treatment can help maintain the system in good condition.
There are products on the market which can help treat the effects of soil-mineral bonding if you live in an area where clay soils are common.
Unfortunately if poor design, installation or soil compaction is a problem, the best remedy is probably reconstruction of the drainfield or an alternative system design. Your professional septic company should be able to help in this area.
FAQ NOTE: HOW DO YOU TELL IF YOU HAVE A HIGH WATER TABLE. A: DIG A HOLE OFF TO THE SIDE OF THE DRAINFIELD OR TRENCHES. IF NO STANDING WATER AT THE LEVEL OF THE LATERALS, THEN WATER TABLE IS NOT ISSUE.