Ann Arbor cannot impose true development impact fees on ADUs because Michigan law forbids them. The Michigan Supreme Court in Bolt v. City of Lansing, 459 Mich 152 (1998), held municipalities lack authority to charge impact fees without specific statutory authorization. ADU costs are limited to Building Department permit fees and water/sewer connection charges.
Michigan is a Dillon Rule state on municipal taxing power. The Michigan Supreme Court's decision in Bolt v. City of Lansing, 459 Mich 152 (1998), held that municipalities cannot impose general residential development impact fees disguised as user charges; only true user fees tied to actual service capacity are permitted. The Michigan Legislature has not subsequently authorized a general impact-fee statute. As a result, Ann Arbor's ADU costs are limited to: Building Department permit fees calculated from construction valuation under the City fee schedule; separate trade permit fees for electrical, mechanical, and plumbing work; and Ann Arbor Water and Wastewater Treatment connection charges if a new service connection or upsized meter is needed. There is no school impact fee, parks impact fee, transportation impact fee, or affordable-housing in-lieu fee tied to an ADU. Property taxes will adjust upward when the assessor revisits Taxable Value after the ADU is added, but that is a property tax consequence governed by Headlee (MCL 211.34d) and Proposal A, not an impact fee. ADUs sharing existing water and sewer service with the primary dwelling generally pay only minimal additional charges.
Bypassing permits avoids fees but exposes the property to stop-work orders, double permit fees on after-the-fact applications, and municipal civil infraction citations. Unpermitted utility connections may result in service disconnection by Ann Arbor Water/Wastewater until corrected.
Ann Arbor, MI
Ann Arbor prohibits storing abandoned, inoperable, or unregistered vehicles on public streets or visible on private property. Vehicles may be tagged and towe...
Ann Arbor, MI
Ann Arbor regulates electric vehicle charging infrastructure for residential and commercial properties. Building codes may require EV-ready parking in new co...
Ann Arbor, MI
Ann Arbor regulates overnight parking on public streets. Many areas restrict parking between certain hours or require permits for overnight street parking.
Ann Arbor, MI
Ann Arbor requires pool barriers meeting safety codes to prevent drowning. Fences must be at least 4 to 5 feet tall with self-closing, self-latching gates.
Ann Arbor, MI
Ann Arbor requires permits for retaining walls above a certain height, typically 4 feet. Engineering review may be required for taller walls.
Ann Arbor, MI
Ann Arbor restricts or prohibits intentional feeding of wildlife including deer, coyotes, and bears. Feeding wildlife creates public safety hazards and nuisa...
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