The Frankford elevated line, which was completely rebuilt in the 1980s and 1990s to last for 75 years, needs significant repairs because of a basic flaw in its reconstruction design.
To prevent pieces of concrete from falling onto cars or pedestrians, SEPTA crews have installed 8,000 metal mesh belts on the underbelly of the El and plan to install 2,000 more, beginning Monday.
That’s a temporary fix, designed to keep the 5.2-mile-long El safe until SEPTA consultants come up with a permanent repair in the next year.
The problem? The El was rebuilt in a way that does not allow its deck to adequately expand and contract with temperature changes, SEPTA chief engineer Jeffrey Knueppel said.
Repairs could cost $20 million or more, Knueppel said.