It’s not just law enforcement that is lamenting the lack of funding for treatment of substance use disorders. A 16-bed residential treatment center in Portland is ending its program Friday due to fiscal challenges. Gov. Paul LePage once called the center, Serenity House, a model for treatment. But Serenity House’s executive director said insufficient state reimbursements and restrictions on the number of treatment beds forced the program to end. Seven years ago, the governor made an official visit to Serenity House.