A number of problems can cause failure, including solids filling the septic tank, tree roots, excessive grease from the kitchen, overloading and excessive water. Leaking plumbing fixtures should be repaired immediately, because a continuous leak can saturate the drainfield and cause failure of the system. Water-saving shower heads and plumbing fixtures and other water conservation measures are beneficial. It is a good idea to direct surface water away from drainfields to allow more absorption from the tank. It may become necessary to add a waste pump to pump the effluent to an alternate drainfield in another site.
Some advantages exist in alternating the use of drainfields if a second drainfield can be added.
If flow is diverted to another field and the ailing field is rested, the biological substances causing the soil to clog will break down over a period of time. A diversion valve can be used to control flow to the newly constructed field. Allowing six to 12 months of rest for the failing field often allows the biological breakdown of the substances plugging the soil. Other methods to remedy failing drainfields have been tried. One method is to flush the drainfield with hydrogen peroxide.