When your septic tank is overly full with sludge, the solid waste matter will overflow into the soil around the drain field. This can damage your septic drain field and cause numerous problems in and around your house, including pollution of your groundwater. There are several signs that your septic tank is full and needs to be pumped. You should pump out your septic tank every three to five years to prevent it from becoming completely full of sludge.

Flushing Toilet
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Step 1

Look for pooling water on your lawn around the drain field area. This indicates that the septic tank is too full and solid particles are clogging your drain field pipes, causing the wastewater to rise to the soil surface.

Step 2

Notice any foul odors in and around your house. Odors from backed-up waste will be especially noticeable above your septic tank and around the drain field area.

Step 3

Look for drains and toilets that take a long time to drain, despite using a plunger or drain-clog removers. This indicates a full septic tank that isn't operating properly.

Step 4

Look for sewage backing up into your sinks, bathtubs or toilets. Look for a foul-smelling black liquid.

Step 5

Study the grass growing over your drain field. Notice whether it's much greener and healthier-looking than other areas in your lawn.

Step 6

Test your well water to detect nitrates or bacteria in the drinking water. Bacteria and nitrates may be leaching into your well water from the septic wastewater that isn't draining properly in the clogged leach field.