Sump pump failing in spring: a Michigan checklist before the thaw

What the sump pump is doing in your basement

A sump pump sits in a pit at the lowest point of a basement or crawl space. Water from the drain tile around the footing collects in the pit, and when the level rises a float lifts and switches the pump on. The pump pushes the water up and out through a discharge pipe, with a check valve to stop it falling back. It is one of the few things in a house that does its whole job once a year, in an emergency, with nobody watching.

That is why spring is a poor time to find a problem. The Michigan State Police’s flood facts say floods can occur at any time but many occur seasonally after winter snow melts or heavy spring rains, and they recommend adding a sump pump and sewer backflow valves as protection. The National Weather Service puts it briefly: make sure your sump pump is working, and consider having a backup.

Power is the usual weak point

The State Police’s mitigation brochure, written after the Midland flooding, says basement flooding occurs more often by sump pumps failing due to power outages than by sewer water backing up. It lists three redundant backup types. Think about what that means. The storms that raise the water table also knock out power, so a pump that works perfectly on a dry day does nothing once the neighborhood goes dark. If your list has room for one fix, a backup that does not depend on house power is the one the state’s own guidance points to.

Backups come in several forms, and the plumber who services your pump can tell you which fit your pit and your wiring. We give no figures for battery life or for what each type costs, because we have no Michigan source for them. The sump pump page has the cost evidence we do hold.

A test you can do this week

Do it in the dry weeks, before the storm.

1. Look in the pit. Remove any debris you can see, and note whether there is standing water before you start.
2. Pour in enough water to raise the float. A bucket or two is the usual way.
3. Watch the pump start, empty the pit and shut off. It should not run on and on, and it should not grind or rattle.
4. Walk outside and check that water is leaving the discharge pipe and that the pipe end is not blocked or buried.
5. If you have a backup, test it on its own, as the manufacturer describes.

A pump that does not start, does not stop, or does not move water out needs a repair call. After a hard cold snap, look at the outdoor end of the discharge line before the thaw, because a line blocked outside has nowhere to send the water.

Where the water may go

This is the part that causes neighbour disputes and, in some cities, fines. No single Michigan law on sump discharge turns up in what we read; the rules are local. Midland, for instance, says it has been illegal since 1987 to connect a property’s footing drain to the sanitary sewer, and it names sump discharge into the sanitary system as a backup risk. Other Michigan municipalities have similar rules, though search results are all we have seen of them. In Sterling Heights, engineering standards adopted in 2024 call for each lot to have a sump pump outlet to the lot line connected to a storm sewer, and an outlet directly into a storm structure needs the City Engineer’s approval. That comes from a search summary, so confirm it with the city.

EGLE’s guidance on residential sump pump discharge, also read through a search summary, prefers discharge to the ground where it can soak in without erosion or ponding on neighbouring land. It says a storm sewer connection needs the approval of the system owner, and that sump or softener discharge should not be connected to a septic system. Floor-drain discharges are not authorised.

If your pump currently sends water to a sanitary drain, do not move the pipe yourself on the strength of this page. Call your city’s building or public works office first, then a licensed plumber.

What insurance may and may not do

The DIFS says water and sewer back-up is not automatically covered under a homeowners or renters policy, and that flood damage is typically not covered without flood insurance. The Michigan flood facts note that sump pump and water backup coverage is optional, with limits and terms that vary by insurer. Ask your agent what your policy says about a failed sump pump, and when the day comes, tell your insurer there is water damage and name the cause. The DIFS says causes like a failing sump pump may be covered.

Michigan’s law on claims for sewage disposal system events adds a wrinkle: it excludes backups where a substantial cause is a connection on your property, such as a sump, building drain or downspout. If you are weighing a claim against a municipality, read sewer backup after heavy rain and talk to a lawyer about the 45-day written notice.

Permits and who does the work

Whether a sump pump swap that does not alter piping needs a permit is a question for your local building department, as we have no authoritative source on it. Where plumbing permits apply, fees vary: Sterling Heights lists $25 for a sump or interceptor on its 2026-2027 chart, plus a $55 application fee. Under Michigan’s license rule only a licensed master or journey plumber may perform plumbing, with narrow exceptions, and our guide to finding a licensed plumber shows the lookup.

When it is an emergency

If water is rising in the pit and the pump will not run, the problem is live. Do not stand in water to work on anything electrical, and keep out of the basement if water is near the panel or outlets. Call a plumber; our emergency plumber page explains how to request help. If you are on the buying side of a house with a sump, whether a sump pump is a red flag covers what to ask.

Metro Detroit saw widespread 3 to 5 inches of rain in June 2021, with flooded basements reported on June 26. A working pump matters in any season that brings rain like that.