The cause of the June sewer main break in Miami-Dade County that spilled an estimated 20 million gallons of raw sewage into Biscayne Bay was the “catastrophic failure” of the reinforcing wire in the 6-foot pipe, according to Vicente Arrebola, an assistant director at the Miami-Dade Water and Sewer Department.
The type of pipe used, a pre-stressed concrete cylinder pipe, was manufactured by Interpace Corp. and installed in 1978. Interpace is now out of business, and the class IV reinforcing wire used in the pipes has suffered “a significantly high number of catastrophic failures nationwide,” according to Arrebola. The county is now doing a metallurgical analysis of the reinforcing wire throughout 100 miles of PCCP in the county system, Arrebola notes. The county may be faced with a large-scale and costly effort to prevent further breaks from occurring.