How to Unclog a Sump Pump in 5 Steps

Start by unplugging your sump pump’s electrical connection and detaching the pump’s discharge lines. Once it’s unplugged and the lines are detached, lift the pump from the sump basin. 

To clean the sump pump, use a rag to wipe it down. If it’s really dirty, take it outside and hose it off with water. It’s a good idea to place the sump pump into a large bucket or inside a trash bag to collect any water drips and prevent a mess on the floor.

Use a flashlight to look inside the entry and exit of the drain discharge lines. In many instances, the reason why a sump pump is not working or draining is because of large pebbles and other debris getting lodged in the lines. This prevents water from entering and exiting the discharge lines from the sump pit. As part of your regular sump pump maintenance, it’s a good idea to check the entry and exit of your discharge lines to ensure they’re clear. 

If you see a clog in the discharge lines or the sump pit and it’s accessible, you can use your rubber-gloved hands to scoop out the debris. However, clogs deeper in the line require a snake. Here’s how you can snake a clog from the discharge lines:

1. Push the snake into the lines until you feel resistance.

2. Begin to twist the snake clockwise and counterclockwise. This helps loosen the clog.

3. Slowly pull the snake out of the discharge line and remove any clogged debris from the snake.

4. Repeat until you no longer feel resistance when putting the snake into the lines.

When your sump pump brings in water from outside, it can also bring in dirt, sand, and other sediment, which builds up over time. Sometimes, the sediment will build up near the front of the discharge lines, which you can easily scoop out by hand or scrape out with a screwdriver.

But you might discover the blockage is further in the lines, making it not-so-easy to reach. In this case, you can use a wet/dry shop vac or a drain snake to help clear the clog. If you still have issues after several passes with a wet/dry vac or snake, the issue might be too severe to fix yourself, so call in a pro to help.

Once the discharge lines are free of clogs and blockages, test the sump pump to make sure it drains easily. Here’s how you can test the lines:

1. Fill a 5-gallon bucket or other large container with water.

2. Dump the water into the sump pit.

3. Turn on the sump pump.

4. Check that water is coming out of the discharge pipe.

5. If the water releases from the pipe, you’ve successfully cleared the clog.

6. If the water stays in the pit or drains slowly, there is still a clog in the sump pump system.

Once your drains are cleared, reattach the sump pump to the discharge lines and power source. Place the sump pump in the sump basin, making sure it’s centered and level. Plug the sump pump back in to turn it on.

Again, fill the sump pit with about five gallons of water to test that the pump works and is attached properly to the discharge lines. Once the pit is filled with water, it should activate the pump’s system to drain the water. If the sump pump is not working, you may have reinstalled it incorrectly or the discharge lines could still be blocked.