Discolored tap water afflicted Goldman’s Lower Manhattan headquarters in July. The annoyance, familiar to anyone who has spent time in New York City, caused some hand-wringing (if not hand-washing) among the firm’s employees, for whom 200 West Street is usually a sanctuary of comfort. Water used for coffee and ice took on a yellowish color, and theories percolated among the staff as to what might be behind it. The construction at the World Trade Center site down the street? The fact that the building, which opened in October 2009, was still relatively new? Something else entirely? [...] The cafeteria, located on the 11th floor, began serving free coffee, apparently using an alternative water source. Service workers made the rounds, stocking the firm’s pantries with water bottles. But not everyone was satisfied. “People were hoarding water,” said one employee, who asked not to be identified because she was not authorized to speak publicly about the matter. “People would take two, three bottles of water at a time rather than just take one.” [...] “We took these precautions out of the utmost of caution,” David Wells, a Goldman Sachs spokesman, said in a statement, “but tests of the water showed there wasn’t a problem with the quality.” [Dealbook]