Basement Waterproofing in the Grosse Pointes

Grosse Pointe is five separate cities: the Park, the City of Grosse Pointe, the Farms, the Woods and the Shores. Each runs its own sewers, enforces its own downspout rules and staffs its own building department, and those differences decide what floods a basement on your street and which repair fits. For one city in depth, see our Grosse Pointe Park, Grosse Pointe Woods and Grosse Pointe Farms pages.

How do the five Grosse Pointes compare?

The houses and the ground are more alike than the rules. Four of the five have a median build year before 1960, and most of their land is wet lake-plain soil.

City	Median year built	Built 1939 or earlier	Main soils and USDA basement rating
Grosse Pointe Park	1939 or earlier	62%	Lake-plain loams and clay till; most of the city rated “Very limited”
City of Grosse Pointe	1939 or earlier	60%	Ziegenfuss clay till and Kibbie lake loam; mostly poorly or somewhat poorly drained
Grosse Pointe Farms	1946	36%	Ziegenfuss clay near Mack; Brems sand along Kercheval and Kerby
Grosse Pointe Woods	1953	12%	Mostly Ziegenfuss clay till, rated “Very limited”
Grosse Pointe Shores	1961	10%	Livonia on about half the land: sand to about 4.5 ft over dense clay; rated “Somewhat limited” (Ziegenfuss and Colwood patches “Very limited”)

Across the five cities, about 93% of roughly 19,200 homes were built before 1980 (Census ACS 2020–2024). In most of the Woods and the Park, USDA rates the soil “Very limited” for basements because it stays saturated near the surface for part of the year. Toward the lake, in the Shores and on the Farms’ lakeside streets, the top few feet are sandier and drain faster.

Why do basements leak in the Grosse Pointes?

Mostly because old foundations sit in soil that holds water against them. Ziegenfuss, the clay-till soil under much of the Woods, the City and the inland Farms, carries a perched water table from about 6 inches above to 6 inches below the surface from October to May in its natural state (USDA series description). Fill lowers that wet zone, but the USDA soil survey still puts it about 20 inches down in spring.

That water pushes in through cracks, along the joint where the wall meets the floor and past old drain tile that no longer carries it away, which is why seepage tends to follow long wet spells and spring thaws. More in our hydrostatic pressure guide.

Downspout rules add to the load. All five Pointes bar downspouts from the sanitary or combined sewer, so on older houses roof water can end up beside the foundation if the discharge isn’t routed away. The City’s, Park’s and Shores’ ordinances even list, as grounds for an exemption, that disconnecting would send water next to a basement wall. If yours empties at the wall, start with exterior water management.

Were the Pointes’ big basement floods sewer backups or seepage?

The biggest floods the Pointes have documented were mostly sewer backups: water forced up through floor drains when pipes and pump stations couldn’t keep up.

• Farms, May 25, 2011: 288 flooding calls, all residential, after the storm topped what the combined sewers and the Kerby/Chalfonte pump station could handle (council minutes).
• Park, June 25–26, 2021: 8.19 inches of rain, the top total in the National Weather Service report; the Grosse Pointe News later tied sewer and runoff backups in 3,000 Park homes and businesses to that storm and, to a lesser degree, a second one on July 16.
• City: all sanitary lines end at the Neff Road pump station, and the City warns that when it is overloaded, backups can reach homes anywhere, even south of Waterloo (City FAQ).
• Woods, 2021: Public Works logged 264 flooded basements, up from 16 the year before, and blamed the June and July storms without saying how the water got in (DPW report).

Exterior waterproofing does not stop a sewer backup; that is a licensed plumber’s job, usually a backwater valve. In the Park, a footing drain tied into the sanitary lateral must be disconnected before a sanitary backflow device goes in. Exterior work fixes the other water: seepage through walls, cracks and the floor-wall joint once the ground is saturated. See how to tell a backup from seepage, or book a leak diagnosis.

City	Sewer system	Downspout rule
Grosse Pointe Park	Close to 95% separated; storm water pumped to the lake; a last-resort relief valve the city says was never needed	§14-21: none on the sanitary sewer, sump pumps included
City of Grosse Pointe	Mostly separate pipes, but all sanitary flow and the storm water north of Waterloo go to the Neff Road pump station	§78-72, since October 2021
Grosse Pointe Farms	Lakeside District separated in the early 2000s; Inland District combined, partial separation under way through 2027	Code 11-10: none on the combined or sanitary sewer
Grosse Pointe Woods	Combined sewer, sent to Wayne County’s Milk River basin	Ordinance 86-241: all disconnected
Grosse Pointe Shores	Separate sanitary and storm sewers; sanitary flow to the Southeast Macomb Sanitary District	Chapter 36: none on the sanitary sewer

What the Farms project will and won’t fix is answered below and on our Grosse Pointe Farms page.

If sewer water reached your basement, Michigan law gives you 45 days to notify the city in writing (MCL 691.1419).

What local rules shape an exterior dig in each Pointe?

Each city has its own building department, and only the Shores names waterproofing on its permit form. We pull the permits the job needs ourselves.

City and building department	Waterproofing permit	Other rules near a dig
Grosse Pointe Park (313) 822-4365	Not named; call if unsure	Construction and digging 7 a.m. to 6 p.m. on weekdays only, unless the City Manager grants a permit (§28-226)
City of Grosse Pointe (313) 885-5800	Not published; call	No digging within 5 feet of a public tree without written permission (§82-58)
Grosse Pointe Farms (313) 885-4285	Not named; call	A Wayne County soil erosion permit before any earthwork within 500 feet of the lake
Grosse Pointe Woods (313) 343-2426	Not named; digging on private property needs a permit unless a building permit covers it (Sec. 20-29)	No digging within 6 feet of a city tree without permission (Sec. 46-62)
Grosse Pointe Shores (313) 881-6565	Yes, a Building, Roof & Waterproofing permit	City handout: even hand digging can damage buried lines

Footing drains have their own rules. The Park’s §14-22 makes a footing drain on the sanitary sewer illicit even if the city once allowed it, and both the Park (§14-52) and the City (§78-68) list footing drains among discharges allowed into the storm system. Where new drain tile can drain depends on your street and your city.

Selling soon? The City and the Woods inspect basement walls at sale, and the Park and the Farms check downspouts.

What should City of Grosse Pointe homeowners know?

The City’s housing is nearly as old as the Park’s: about 60% of its homes were built in 1939 or earlier (Census ACS 2020–2024), and its Master Plan says most single-family homes date to the 1920s and 1930s. The same plan puts the narrowest lots, on Notre Dame and on St. Clair and Neff near the Village, at 30 to 40 feet wide.

The City’s big public fix has stalled. FEMA confirmed funding in 2023 for a new storm sewer north of Waterloo, but a 2025 change in its cost-benefit rules dropped the project below the qualifying score (City update), and in April 2026 the City Manager told council to explore alternatives (draft minutes). Until something is built, protection happens house by house.

The City adopted its downspout disconnection ordinance in October 2021 (§78-72) and enforces it at sale and through a citywide exterior inspection program.

Where do our six services fit in the Pointes?

• Exterior basement waterproofing: for walls in the wet clay till under most of the Woods, dug by hand to the footing and sealed from outside.
• Foundation crack repair: sealed on the outside face, before a point-of-sale inspection like the Woods’ looks at your basement walls.
• Basement leak diagnosis and repair: backup or seepage first, since the Pointes’ biggest documented floods were mostly sewer backups through floor drains.
• Drain tile replacement: new tile in pea stone; where it drains depends on rules like the Park’s §14-22.
• Exterior water management: grading and downspout routing, now that every Pointe keeps downspouts off the sanitary or combined sewer.
• Waterproofing under porches, decks and concrete: when a walk, driveway or porch covers the leaking wall; the Woods lists installing all three as work that needs a permit.

Every foundation we waterproof is dug by hand, with no backhoes.