The Detroit Water and Sewer Department have disconnected water to thousands of Detroit residents who are delinquent with their bills. But will they go after the delinquents that can fight back, such as Chrysler and the state of Michigan? - 

Detroit threatened residents behind on their water bills in March: Pay up, or we’ll shut you off. The story has been building up ever since. 

Here's what you need to know:

The threat applies to about half the city's water customers. Before declaring a 15-day moratorium last week, the city did turn off the taps on thousands of households, setting off protests, official condemnation from human-rights experts at the U.N., and grumbling from the judge overseeing the city’s ongoing bankruptcy case that the city already has enough public-relations problems.

It's a scare tactic, but it's working. Latimer says the residential shutoffs were always intended as a scare tactic, to combat what he calls "a culture that’s developed: 'Since you’re not cutting me off, I’m not going to pay you.' And what we’ve found when we shut residents off is that 60 percent are coming in and paying."

It's not just private citizens. Corporate customers— including both private companies and branches of the government— have also fallen behind on their bills, to the tune of millions of dollars. Why didn’t the city shut them down first? Officials say they have turned off close to 19,000 residential accounts, but could not provide a number for corporate customers.

Darryl Latimer, the Water and Sewage Department’s deputy director says he’s been going after corporate deadbeats, too. Often, they’re disputing part of their bill, and negotiating takes time. He says that paid off with Chrysler Group: The company gave Detriot a check for $2.9 million— and the city recognized that Chrylser no longer owns some of the properties that were in dispute. The Detroit Public Schools, he says, have paid off about three quarters of a $12 million tab.

Customers are reporting difficulties in dealing with the water department. Shea Howell, a volunteer with the People’s Water Board Coalition, says residential customers do not get similar treatment. "Many, many resident also have problems with their bills," she says. "They also have problems they’d like to talk with the water department about, and they can’t even get through on the water department’s service lines." She says customers report wait times of up to four hours on hold.

What makes this unique? The scale of Detroit’s problems make it unusual, says Janice Beecher, director of the Institute for Public Utilities at Michigan State University. "What we don’t have in the water sector is a really clear policy for coping with something like this, so in some ways it’s a learn-as-you-go process," she says. "I do think it will go down as a case study in this sort of problem."

Residential shutoffs are due to resume next week.

An interesting campaign spawned from Twitter. Detroit’s water shutoffs also prompted some Twitter users to create an online platform where donors can directly pay off the water bill for a Detroiter in need.

Follow Dan Weissmann at @danweissmann