It's not all good news amid the campus housing booms transforming North and West Philadelphia and college towns around the U.S.

While just two of the dozens of Philadelphia-area apartment-building loans tracked by investors in mortgage-backed securities are currently "in special servicing" and close to default, "both are student housing complexes," notes Sean J. Barrie, research analyst at Trepp LLC in New York. Both properties are operated by Campus Living Villages, an Australian investment company backed by pension funds.

TEMPLE: Writes Trepp in a report: "According to May servicer data, the $52.6 million The Edge at Avenue North loan has been sent to special servicing." The loan on this 799-unit property at N. Broad and W. Oxford Sts in Philadelphia, on property adjoining Temple University (corrected), is for more than the property is now worth.

Edge lost students when Temple opened its new dorms nearby. Built in 2006, "the property has negative cash flows since 2013."

DELAWARE: "The $28.3 million Studio Green Apartments loan has been sent to special servicing and is facing imminent default. A letter from the borrower notes that the 'property's net cash flow is not sufficient to cover the scheduled debt service.'" Studio Green sprawls over 1,074 units just east of the University of Delaware campus in Newark, Del.

Built in 1967, it was renovated six years ago by Campus Living's development arm.

Do these problem complexes signal a slowdown -- and uncertain returns -- after the long college-housing boom?

Not according to David J. Adelman, West Philly-based boss of Campus Apartments, which controls more than 25,000 off-campus units nationwide: "These are both unique circumstances," he told me. For example, Studio Green is more "traditional multifamily" than the more recent student projects transforming Newark. "I would not view these as symptomatic of any student housing issues."