Some further details regarding the closure of the Aviary. In brief, the aviary had significant structural issues that included corrosion to mechanical systems and pipes, issues with the glass roof panels, and even erosion that could lead to a sinkhole! The aviary was not only beyond salvation, but it cannot be rebuilt in the same spot.
The zoo estimated that rebuilding the aviary would cost north of $50 million.
Rebuilding NC Zoo’s aviary would cost $50 million, zoo director says :: WRAL.com
Not even the Desert is 'safe"! An inspection in March revealed cracks in some of the exterior walls and support columns, corrosion to various mechanical parts, as well as an emergency generator that needs replacement. The report estimates these repairs could cost $1.6 million.
Thankfully, that seems much more feasible, and the report stated that the Desert is otherwise "in good condition" and just needs some repairs, hopefully indicating that it will not meet the same fate.
NC Zoo desert exhibit needs repairs, according to state report | wfmynews2.com
Expect the Desert to close for repairs sometime in the future.