Cold Great Lakes water
Detroit and its suburbs draw from the Detroit River and Lake Huron, Grand Rapids from Lake Michigan, and other cities from inland lakes, rivers and wells. Great Lakes water is moderately hard; groundwater in parts of the state is harder and may carry iron. In winter, incoming water falls into the 30s, so tanks recover slowly and households often need a larger or high-recovery heater.
Basements, chimneys and floods
Basement installs are standard. When furnaces are upgraded to high-efficiency models, gas water heaters can be left in oversized chimneys that draft poorly in cold weather, so draft tests matter. Heavy storms have flooded basements in Detroit and other cities; any gas heater that sat in floodwater should be inspected and usually replaced.
Licensing, permits and costs
Michigan licenses plumbers through the Department of Licensing and Regulatory Affairs, and local building departments issue permits. Typical repairs run $150 to $600, and a gas tank replacement usually costs $1,300 to $3,000. See water heater replacement for details. Pick a city below for local specifics.