Can a Metro Detroit Water Deal Exclude Oakland and Macomb?

Concerning an anticipated metro Detroit water deal that would exclude Oakland and Macomb counties, reported in the Detroit Free Press* on January 22, 2014 by John Wisely:

How likely is it that Gov. Snyder, having in mind a re-election bid, would risk losing Republican campaign money and votes in Oakland and Macomb counties by siding exclusively with 99 percent Democratic Detroit and Wayne County’s discredited executive, a Democrat, on a water pact?

* http://www.freep.com/article/20140122/NEWS05/301220028/detroit-water-sewerage-department-suburbs-cooperation-deal