The majority of septic systems rely on gravity to move processed waste water from the tank to the drain field lines. In certain areas, the landscape or distance between the system components will not permit a gravity system to be used. In these instances, an electric pump must be installed in the septic tank in order to remove the water.

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Tank wiring should be in a weatherproof box.

Step 1

Install direct burial cable from the breaker box of your home to the septic tank. It is best to lay this cable directly beneath the drain line when it is installed. The drain line will then offer protection for the cable against a misguided shovel or other item. If at all possible, the septic tank pump should be on a dedicated circuit.

Step 2

Wire the cable to a weatherproof electrical box located outside the septic tank. Electrical codes do not allow for any electrical junctions or boxes to be placed inside a septic tank. Once the box is in place, the cable can be wired into the breaker box. If you are not familiar with electrical work, it is advisable to have this work completed by a licensed electrician.

Step 3

Route the plug wire from the septic tank pump up and out of the tank to the new electrical box. There will normally be separate wires for the pump controls. The pump will be controlled by a float or other switch, which will activate the pump when the water reaches a pre-set depth.

Step 4

Use piggyback plugs for the control wiring. This is where control plugs and the pump power wires plug into an electrical outlet. This will leave the pump power and controls on the same dedicated circuit. These electrical connections must be outside the tank, but must also be at ground level, rather than buried.