What is Septic System Biomat Clogging?

While some septic problems can be easily corrected by pumping your septic tanks, other problems, such as biomat clogging, require more extensive investigation and repair. Biomat clogging can slow the movement of wastewater into the surrounding soil, which can lead to effluent back up or surfacing.

Biomat is a naturally occurring, tar-like substance comprised of anaerobic microorganisms that attach to one another and then form a layer along the bottom and sides of the drainfield trench. The biomat is a necessary component of septic systems, as it treats and reduces biological solids and pathogens in wastewater. However, when the biomat clogs soil and the absorption system fails, the experts have to step in.

When biomat clogging occurs, the biomat inhibits the passage of liquid though it, so eventually less liquid is absorbed by the drainfield than the amount of liquid entering the septic system. When liquid cannot be absorbed at an efficient rate, the septic system fails, which can lead to bad odor, the formation of pools of effluent in your yard, slow-draining plumbing fixtures, and overflowing toilets.

If you notice liquid or soft spots on your soil over the disposal field or septic tank, notice that your plumbing fixtures are draining slowly or backing up, hear gurgling at the septic lines, or notice a septic odor in or around your house, you may be dealing with biomat clogging.

For more information on biomat clogging, contact SES. Based in Warrenton, Virginia, SES has been inspecting, servicing, maintaining, and repairing residential and commercial Northern Virginia septic systems, in such communities as Purcellville, Woodbridge, Burke, Dale City, Dumfries, and Leesburg, since 1987.

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