Though these were technically “show cause” hearings, offering residents a chance to argue that the county should not foreclose on their homes, the scale made it feel more like an unhappy county fair — complete with workers in yellow vests offering help from an array of nonprofit groups and large signs guiding residents into subgroups like “Nondeed holders including renters” and “Homeowner occupants.” Thursday was the first day of what will be seven days of hearings at Cobo Center, which officials said they had chosen because the proceedings would have outgrown other sites.

Michigan in 1999 changed the way its local governments deal with people who fail to pay their property taxes, replacing a system of tax liens with foreclosure. Yet the number of foreclosures did not reach what advocates here view as a crisis level until years later, when the national recession hastened the city’s problems with blighted properties and population decline. By last year, at least 70,000 foreclosures had taken place here since 2009, not for unpaid mortgages but for failure to pay property taxes.

Of the 62,000 city properties subject to foreclosure this year, more than half are believed to be occupied; nearly 13,000 are probably vacant lots. Some portion of the properties facing foreclosure were also eligible for it a year ago or more, but officials had delayed pursuing them in part because the numbers had grown too large for county workers to handle so many proceedings.

In the coming months, some of these owners will pay their bills or get on payment plans and save their homes, and thousands already had by Thursday night. Some will not even try. Others will meet requirements for assistance in paying their bills, including a state program that uses federal funds — efforts county officials spent much of the day explaining to residents and urging them to apply for.

David Szymanski, the chief deputy for the Wayne County treasurer’s office, said Detroit officials were dealing with the “competing interests” of “collecting taxes that allow services and of keeping people in their homes.”