How to check if your sump pump is working, and what to do if it fails.

A sump pump is easy to forget. It sits in a pit in the corner of the basement and only matters on the night you need it. Most people find out it stopped working when the carpet is wet.

The good news is that testing one takes about five minutes and a bucket. Here is how to do it, what the results mean, and what to do if it has already failed.

How to test your sump pump

Only do this if the floor around the pit is dry. If there is water on the floor, skip to the section on what to do if your pump has failed.

1. Do the quick look. Travelers suggests checking that the pump is plugged in, the power cord is in good shape, the discharge hose is connected, and no debris could clog it.
2. Pour in water. Take off the lid and slowly pour water into the pit. The City of Ann Arbor says 5 gallons should be enough.
3. Watch it start. The pump should start up automatically, and the water should drain quickly.
4. Check the pipe while it runs. Ann Arbor says to look for cracks or breaks in the joints of the discharge pipe inside the house, and to replace any bad sections.
5. Go outside. Find where the water comes out. Travelers says it should not discharge near your foundation, the area should be clear of debris, and it should not go into a septic tank or sewer system.
6. Test the backup, if you have one. Unplug the main pump during the test to make sure the battery backup takes over. Remember to plug the main pump back in.

How often to test it

The City of Ann Arbor says at least twice a year. Travelers says at least once a year, and again when a lot of rain is forecast. For a Michigan home, we would do it in autumn and again before the spring thaw.

If the bucket test does not start the pump

Work through these, in this order, with dry hands and a dry floor:

• Power. Check that it is plugged in and whether a breaker has tripped, and test the outlet with another device.
• The float. Lift the float by hand. If the pump starts, the float was stuck, so it needs to be repositioned to move freely. If you need to clear anything away from it, unplug the pump first.
• The sound. A hum with no water moving can mean a jammed impeller or a blocked discharge line. Do not leave it running like that, because it can burn out the motor.

If none of that works, call a plumber. Most plumbers and some handyman services can repair or replace a sump pump.

Signs your sump pump is going bad

• It starts again within seconds of stopping. This often points to a failed check valve, which lets water run back into the pit.
• It runs but moves less water than it used to. The impeller may be worn or the screen may be blocked.
• It hums but no water moves. See above.
• It runs all the time. See the next section.
• It does nothing when the pit is full. Check the power and the float right away.
• It is getting old. One plumber puts the average life at 7 to 10 years, and another gives the same range.

Why does my sump pump run constantly?

Sometimes it is just doing its job. When the ground is full of water from heavy rain or a long thaw, the pit keeps filling, and the pump keeps running. That is not a fault as long as it keeps the water level down. Call a plumber if it never stops, cannot keep up, or starts sounding different.

If there is no good reason for it to be running, these are the usual causes:

• A stuck switch or float. The pump does not get the signal to stop.
• A failed check valve. Water in the pipe falls back into the pit, so the pump keeps moving the same water.
• A clogged or frozen discharge pipe. The water cannot get out. Frozen lines are worth checking first during a Michigan cold snap.
• A high water table. The pit simply fills fast.
• A pump that is too small. Ann Arbor notes that water coming in faster than the pump can remove it can lead to continuous running and motor burnout.

7 common causes of sump pump failure

This list comes from the City of Ann Arbor’s guide, one of the few official sources on the subject.

Ann Arbor also says manufacturers recommend that the pump be the only thing on its circuit. If you are not sure your outlet is right for a damp basement, ask a licensed electrician.

What to do if your sump pump has failed

1. Stay out of the water until the power is safely off. The CDC says to turn off the main power only from a dry location. If you would have to step into water to reach the panel, call an electrician instead.
2. Work out what kind of water it is. The City of Ann Arbor describes sewer backup as grayish, usually smelly, and typically coming through a floor drain. Water from storms, snowmelt or groundwater is typically clear and odor free. That is a guide rather than a test. If you think it is sewage, keep everyone out and see our page on sewage cleanup in Grand Rapids.
3. Take photos and video before moving anything. Michigan’s insurance regulator also says not to get rid of damaged items until your insurer tells you to.
4. Be careful how you describe it to your insurer. The regulator advises saying you had water damage and asking what coverage you have. Do not simply call it a flood, because a sewer backup or failing sump pump may be treated differently.
5. Call the right people. A plumber fixes the pump. A restoration company removes the water and dries the building. If the water reached finished rooms, you will likely need both.
6. Get it dry quickly. The EPA says that if wet materials are dried within 24 to 48 hours, in most cases mold will not grow. Our guide on how long mold takes to grow explains more.

For the full step-by-step cleanup, see what to do if your basement floods.

How long sump pumps last and what replacement costs

Plumbers commonly quote a life of about 7 to 10 years. One rule of thumb: if the pump is under 5 years old and the problem is a single part, such as a float switch or check valve, repair is usually worth it. If it is over 10 years old, has failed before or the motor is shot, replacing it usually makes more sense.

As for price, Mr. Pipey, a Metro Detroit plumber, says most replacements cost $400 to $1,200 for the pump and professional installation. Battery backups, pit work, discharge line repairs or electrical updates can raise that. It is one company’s figure, and we do not sell pumps, so get a quote from a local plumber.

Sump pump backup options

• Battery backup pump. Ready.gov suggests considering a sump pump with a battery, because the storm that fills your pit can also knock out the power. It will not run forever. Mr. Pipey says a new, fully charged battery can typically manage about 5 to 7 hours of continuous pumping.
• Generator. Ann Arbor lists this as the other option in an outage. The CDC warns never to run one inside, or within 20 feet of doors, windows or vents.
• A spare pump. Ann Arbor notes that some homeowners install a new pump and keep the older one, with a new switch, as an emergency backup.
• Water-powered backup. These run off your home’s water pressure. Ask your plumber whether one suits your home, and what your city requires.

Sump pumps and sewer backups in Grand Rapids

If you live in Grand Rapids, there is one local issue worth knowing about. The city explains that a footing drain is a series of pipes around and under your home that moves groundwater and stormwater away from the foundation. In some homes, those drains connect to the sanitary sewer. Too much of that water can overload the sewers, and the result is sewer backups in basements in many parts of the city.

• The disconnection program. The city redirects this water to the stormwater system through its Footing Drain Disconnection Program. It sends information packets to homes in neighborhoods it targets.
• What it costs you. The city says the program generally covers all expenses.
• Is it optional? When your neighborhood is targeted, the ordinance requires homeowners in the project area to take part. Opting out means a monthly charge.
• Sewer backup claims. The city says these must be filed within 45 days. If sewage came up in your basement, do not wait.
• Other city help. The city has a policy on backwater valves, sump pumps and footing drains. We could not confirm its current funding, so call 311 or (616) 456-3000 and ask whether your home qualifies.

Does insurance cover sump pump failure?

Usually not without an add-on. Travelers describes water backup and sump pump discharge or overflow coverage, which can help cover the loss up to a specified dollar amount and does not include flood or surface water. Names and limits vary by insurer.

Check whether you have it and what the limit is, because a low limit may not cover a finished basement. Our guide to what insurance covers when a basement floods goes through each cause.

Frequently Asked Questions