Metro Detroit is under a flood watch through late Thursday night, and the Detroit Water and Sewerage Department isn’t waiting for the water to rise before asking residents to act. Cut water use now. That’s the ask.

It’s not a vague precaution. Southeast Michigan has already taken 1.5 to 4.5 inches of rain over the past 10 days, and the ground is saturated. The National Weather Service’s Detroit/Pontiac office confirmed that before any new rain falls, the region’s soil can’t absorb much more. Detroit’s sewer system is already running harder than it should be for late spring. Layering another 1 to 1.5 inches of rainfall on top of that, which is what’s expected between Tuesday night and Thursday night, puts basements across the city at real risk of backups.

What DWSD Is Asking You to Do

Don’t run the dishwasher. Don’t run the washing machine while it’s raining. If your home has a backwater valve, that rule extends to toilets, drains, baths, and showers while rain is actively coming down. The backwater valve can’t do its job when water’s still moving through the pipes inside your house.

Outside, walk to the catch basin in front of your house at the curb and clear it. Leaves, debris, whatever’s sitting on the grate needs to go. Skip the temptation to drive through standing water. Don’t walk through it either. DWSD is direct on this point: flooded streets and downed power lines aren’t situations you test. Stay away.

If your basement floods and the water reaches electrical outlets or the fuse box, don’t go in. Full stop.

Residents can report flooded streets and basement backups through the Improve Detroit app or by calling 313-267-8000. Both are active.

The Storm Window

Metro Detroit counties are under a tornado watch until 4 a.m. Wednesday. The worst of it should push through in a narrow band, with the line of thunderstorms expected between 11 p.m. Tuesday and 4 a.m. Wednesday. That’s a short window but a dangerous one. There’s a slight risk of winds hitting 60 mph, hail an inch in diameter or larger, possible tornadoes, and flash flooding, all within that same stretch.

Total rainfall through Thursday sits somewhere between 1 and 2 inches for most of the region. But 3 to 4 inches isn’t off the table, depending on where the storm line tracks and whether the thunderstorms hold together or fall apart before arrival. The National Weather Service’s Detroit/Pontiac office is still working with low confidence on that question, which means the difference between a manageable event and a significant one won’t be clear until it’s happening.

That uncertainty is exactly why Bridge Detroit’s coverage of Tuesday’s early warnings is worth reading if you want the full picture of what city officials said before the rain started.

Where the Regional System Stands

DWSD says the city’s sewer infrastructure is functioning as designed heading into this storm. Crews are positioned to respond. The department cleaned more than 600 miles of public sewer last year and cleared more than 8,000 catch basins in 2024. Those numbers don’t make the system flood-proof, but they’re the reason officials aren’t sounding alarms about a system that’s already failing.

Navid Mehram, chief operating officer for wastewater operating services at the Great Lakes Water Authority, said the expected rainfall is within the range the regional system was built to manage. “In anticipation of the approaching large storm event, GLWA is closely monitoring conditions, and the wastewater conveyance system has been fully reviewed to ensure operational readiness,” Mehram said.

The 2023 storm season tested the system hard. The work that followed, the cleaning, the inspections, the catch basin clearing, was supposed to buy some margin heading into 2024 and beyond. This week is one of the first real stress tests of that margin. Three to 4 inches in certain corridors would tell Detroit residents and city engineers a lot about whether those investments held.

For now, the ask is simple. Shorter showers. Skip the laundry. Clear the drain at your curb.