"Forty-seven New York City bridges 'have been found to be both structurally deficient and fracture critical.' That means 'if a single span, beam or joint of such a bridge fails, the whole thing could come tumbling down.' The average New York City sewer main is 84 years old. The average New York City water main is 69 years old.Twenty-six percent of subway signals are more than 70 years old. About 43 percent of all Manhattan roads are 'substandard.'"