A federal judge has blocked—but only in 13 states—a U.S. Environmental Protection Agency-Army Corps of Engineers rule determining when contractors need federal permits to build in and near wetlands and other bodies of water.

The Aug. 27 temporary injunction responds to legal challenges that the 13 states filed. But the controversial rule went into effect in the other 37 states on Aug. 28, as scheduled.

The American Road and Transportation Builders Association has filed a separate lawsuit challenging the regulation.  Like other construction groups, ARTBA opposes the rule because, it contends, the regulation could slow down or prevent projects from being built.

Environmental organizations say they are frustrated with the judge's decision to issue the injunction. Madeleine Foote, League of Conservation Voters legislative representative, said in a statement that blocking the rule "leaves in place an unworkable status quo that jeopardizes the clean water our families, economy and community depend on."