How to Install a Second Sump Pump

Sump pumps remove unwanted water from areas such as basements or crawlspaces. In some instances, it may be necessary to install a second sump pump. The second pump can also serve as a backup should the primary pump fail.

Dig the sump pit

Select the proper location for the second sump pump. By adding a completely separate sump pit you are doubling the absorption and pumping ability and are creating a complete backup system in the event of system failure. The second sump pit should be located in an area where water gathers, at a reasonable distance from the first unit to affect more area.

Dig the sump pit hole slightly larger than the sump pump liner you have selected. The bottom of the pit needs to be level, and all sides should be free of any protruding items, such as rocks or large roots that could damage the liner.

Install the liner in the pit. Lay the level across the top of the liner and continue to monitor the level as you pack dirt around the liner to keep it in place. Pack the dirt tightly around the liner allowing no air pockets or gaps of any kind.

Install the sump pump and connect it to an electrical supply. The pump should fit neatly into the pit liner and be slightly offset from center. Most pumps are 115 volts and will plug into a standard GFCI outlet. If at all possible, the two sump pumps should be on separate circuits for added protection and to reduce the chance of tripping a breaker if both pumps activate simultaneously.

Connect the drain line to the sump pump outlet port. Plumb the drain up and out of the pit and to an intersection point with the drain line from the other pump. Cut into the existing line and insert a tee fitting. This fitting must be beyond the check valve for the first pump. You must also install a check valve in the new drain before it joins the existing drain. Once the check valve is in place, connect the two drains lines, making sure all junctions and fittings are secure.

Things You Will Need

  • Pick and shovel
  • Sump pit liner
  • Sump pump
  • PVC pipe
  • Check valve
  • Level


  • GFCI, Ground Fault Circuit Interruption, devices provide additional protection from electrical fires as well as electric shocks.

About the Author

Tom Raley is a freelance writer living in central Arkansas. He has been writing for more than 20 years and his short stories and articles have appeared in more than 25 different publications including P.I. Magazine, Pulsar and Writer's Digest.

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