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Should I add anything to my septic tank?

Biological and chemical additives are not needed to aid or accelerate decomposition. At this time, there is no conclusive data to support the effectiveness of enzymes or any chemical treatment to rejuvenate a failing drainfield. These products are approved by the state of Wisconsin only if they do not harm the septic system. 

How often should I have my septic tank pumped?

Septic tanks require pumping when 1/3 full of scum and sludge. A good pumping interval is every 3 years. 

What are the warning signs of a failing septic system?

1. Plumbing backups

2. Grass in the yard growing faster and greener in the area of the drainfield or tank.

3. Soft or mushy ground in the area of the drainfield.

4. Sluggish toilet flushing.

5. Solids accumulating in the drainfield vent or observation tubes.

What if liquid is observed in the drainfield vent or observation tubes?

Liquid observed in the drainfield usually indicates that the soil absorption capability of the drainfield is reduced and ponding is progressing. Many systems begin ponding within the first few years. The ponding state of a drainfield is usually a slowly developing condition. The estimated life of today's drainfields under normal usage is 15-25 years. The drainfield is ponding to some degree during most of these years. A consistently rising level of ponding is a possible indicator as to the life expectancy of a drainfield. Sludge in a vent pipe or observation tube is an indicator of a more serious condition.

Many lending institutions have been using the observance of any liquid in a vent or observation tube as the sole criteria for rejecting a septic system from a proposed sale or purchase of a home. As noted above, this is a subjective and inaccurate conclusion. A more reasonable condition of sale would be to make sure that there is a suitable replacement drainfield area available for the future if and when the existing drainfield fails. Technical failure of a septic drainfield is when the effluent is bleeding out onto the ground surface, wastewater is backing up into the building (not due to plugged or broken sewer line) or the existing drainfield was installed less than 3 feet to a saturation zone, groundwater, bedrock, or impervious soil.

Can I use my old drainfield later once a new one is installed?

In most cases, yes. If the old drainfield was sized appropriately to its current use and there is at least 3 feet of suitable soil as described earlier, then the owner will be able to switch between the two drainfields by means of a diverter valve. It has been estimated that within a few years, an old ponded drainfield can recover much of its infiltrative capacity. For homes constructed after 1977 and having a below grade drainfield, a future-replacement area will have already been designated. Once a replacement drainfield is installed the original drainfield will be able to rest and rejuvinate. Switching may occur every 1 to 5 years. Your WOWRA member contractor will help you determine the proper time and method for switching drainfields.

What can I do to prolong the life of my drainfield?

There are a variety of things you can do:

1. Install water-saving devices and be on-guard for leaky fixtures. Water conservation reduces the amount of liquid going into the drainfield.

2. Have the tank pumped and inspected regularly.

3. Keep surface water away from the septic area, including the septic and pump tanks.

4. Keep driveways, parked vehicles, and building off the drainfield area. Soil compaction can cause premature failure by restricting the infiltrative and evaporative capability of the soil.

5. Installing an effluent filter to confine most of the suspended soils to the septic tank.

6. The uses of pretreatment components have been shown to improve effluent quality and moderate or reduce ponding.

7. Understand what can and cannot be put into the septic tank.

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