What is your soil telling you?

There are several soil characteristics that can influence your septic field options.

Everyone wants to hear that the soil on their property is ideal to dispose large volumes of effluent at a time. However, properly identifying problems in the soil is very important so that the right septic field is designed. A septic field failure is something very few people want to deal with.

There are certain soil characteristics that are called restrictive. This means that the restrict the flow of effluent in the soil in a way that prevents the effluent from properly being disposed of.

One restrictive item is a water table. It is required that soil properly treats the effluent before it reaches any water. The treatment is done by have a big enough separation distance between the effluent and the water table. Water tables can include actual water, seasonal water, or perched water. Seasonal water and perched water tables can be determined by identifying mottling and gleying in the soil.

Another restrictive item is bedrock. Water does not flow through rock like it will through soil so this stops the flow of effluent.

Platy soil is another restrictive item. Platy soil is a soil that breaks apart in a similar manner to sandstone in horizontal plates. The effluent must go through the soil horizontally before it goes down a little and then it must go horizontal again. This very slow process causes problems with disposal of effluent.

Soil with too high of a percentage of clay is also restrictive. Soil has three main sizes of particles. The first is clay and imagine it is similar to a dime in size. Silt would be similar to a frisbee and sand would be similar to a beach ball in proportion to the clay. Imagine several of dimes together and you will notice there isn’t much air space in between the particles Conversely, the sand has large particles. Effluent moves much better through the sand than the clay. The clay can also plug up with micro particles that are dosed from the septic tank until the bacteria in the soil can dispose of them.

Other items such as salinity, prismatic soils hard pans and more require septic fields to be designed around those restrictive limitations.

There are other factors described as limiting. These would be the items that slow down or limit the flow of effluent. Items such as certain clay soils are limiting.

Besides restrictive and limiting characteristics, several other items are also determined to ensure the septic field is designed correctly. These items include effervescense, color, mottles, gleying, structure, grade, consistence, moisture, coarse fragments, root depth, recent moisture and other items.

It is very important that the septic field designer has all the right information to design a field that will properly dispose effluent into your soils and a proper soils evaluation will provide this.