How to Test Sewer Lines

Louis Gutierrez

Testing sewer lines is an easy task. Your sewer lines, located mostly under your home, are very difficult to change or repair. If you suspect damage to your sewer lines, you should test them. The most often used hydrostatic testing method is the best way to test your sewer lines.

These sewer lines are waiting for installation so you can test them.
  1. Plug the exterior sewer line exit of the residence using the rubber plug. Ensure the plug is the right size.

  2. Locate the farthest toilet in relation to the sewer line exit of the house (which you plugged). It is important to find the right toilet, otherwise you will not be testing the complete sewer lines.

  3. Remove the toilet. Use the adjustable wrench to remove the water supply hoses and the bolts that hold the toilet in place. If your toilet has caulking, use a utility blade to remove it.

  4. Bring your water hose to where your toilet used to be.

  5. Fill up your sewer line, with your water hose. The time it takes to fill up your sewer line varies by the size and complexity of your system. On average it should take you about 10 minutes or less. At this point in time it would be wise to have somebody on the other end looking at the plug to make sure it is not leaking.

  6. Count how long your sewer line is able to hold the water. If it can hold your water for 10 to 20 minutes, your sewer lines passed. If it cannot hold water, it has a leak. At this point it is time to contact a professional plumber to remedy the situation.

  7. Tip

    The cause of most leaks are pipes that have corroded because of their age. Those that are near trees may have cracks because of the tree roots.


    It is very possible that water will come out your shower drain, and other drains in the house.