Posted the other night. Yes, a systematic engineering defect is unusual, and that many replications more so, but not unprecedented. Some employees do confirm chronic plumbing problems.
Local contracts awarded under LPTA (Lowest Price Technically Acceptable) and this what your get. If the people writing the SOW (Statement Of Work) for the contract are not spectacular people with checks and balances, many sets of eyes with many iterations of run-throughs, each with extensive qualifications for plumbing, electrical, cooling, lighting, traffic, etc., then LPTA contracting blows up on you just like this.
Best Value contracting also requires spectacular people for the SOW but there is some give to ensure a good, long-term outcome.